Add the performance white paper.

11 files changed, 988 insertions, 0 deletions

diff --git a/www/performance/graph1.png b/www/performance/graph1.png
new file mode 100644
index 00000000..c713cb68
--- /dev/null
+++ b/www/performance/graph1.png
diff --git a/www/performance/graph2.png b/www/performance/graph2.png
new file mode 100644
index 00000000..179b432a
--- /dev/null
+++ b/www/performance/graph2.png
diff --git a/www/performance/graph3.png b/www/performance/graph3.png
new file mode 100644
index 00000000..0f105892
--- /dev/null
+++ b/www/performance/graph3.png
diff --git a/www/performance/graph4.png b/www/performance/graph4.png
new file mode 100644
index 00000000..4057cf52
--- /dev/null
+++ b/www/performance/graph4.png
diff --git a/www/performance/graph5.png b/www/performance/graph5.png
new file mode 100644
index 00000000..2f273884
--- /dev/null
+++ b/www/performance/graph5.png
diff --git a/www/performance/performance.xml b/www/performance/performance.xml
new file mode 100644
index 00000000..75e4d153
--- /dev/null
+++ b/www/performance/performance.xml
@@ -0,0 +1,475 @@
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<!DOCTYPE article PUBLIC 
+   "-//OASIS//DTD DocBook XML V4.1.2//EN"
+   "docbook/docbookx.dtd" [
+<!ENTITY howto         "http://en.tldp.org/HOWTO/">
+<!ENTITY mini-howto    "http://en.tldp.org/HOWTO/mini/">
+<!ENTITY homepage      "http://catb.org/~esr/">
+]>
+<article>
+<title>Where's the Latency?  Performance analysis of GPSes and GPSD</title>
+
+<articleinfo>
+
+<author>
+  <firstname>Eric</firstname>
+  <othername>Steven</othername>
+  <surname>Raymond</surname>
+  <affiliation>
+    <orgname><ulink url="&homepage;">
+    Thyrsus Enterprises</ulink></orgname> 
+    <address>
+    <email>esr@thyrsus.com</email>
+    </address>
+  </affiliation>
+</author>
+<copyright>
+  <year>2005</year>
+  <holder role="mailto:esr@thyrsus.com">Eric S. Raymond</holder> 
+</copyright>
+<!-- legalnotice>
+  <title>Copyright</title>
+  <para>Permission is granted to copy, distribute and/or modify
+  this document under the terms of the Open Publication License,
+  version 2.0.</para>
+</legalnotice -->
+
+<revhistory>
+   <revision>
+      <revnumber>1.0</revnumber>
+      <date>21 February 2005</date>
+      <authorinitials>esr</authorinitials>
+      <revremark>
+	 Initial draft.
+      </revremark>
+   </revision>
+</revhistory>
+
+<abstract>
+<para>Many GPS manufacturers tout binary protocols more dense than
+NMEA and baud rates higher than the NMEA-standard 4800 bps as ways to
+increase GPS performance.  While working on
+<application>gpsd</application>, I became interested in evaluating
+these claims, which have some implications for the design of
+<application>gpsd</application>.  This paper discusses the theory and
+the results of profiling the code, and reaches some conclusions about
+system tuning and latency control.</para>
+</abstract>
+</articleinfo>
+
+<sect1><title>What Can We Measure and Improve?</title>
+
+<para>The most important characteristic of a GPS, the positional
+accuracy of its fixes, is a function of the GPS system and receiver 
+design; GPSD can do nothing to affect it.  However, a GPS fix has a
+timestamp, and the transmission path from the GPS to a user
+application introduces some latency (that is, delay between the time
+of fix and when it is available to the user).  Latency could be significant
+source of error for a GPS in motion.</para>
+
+<para>The case we'll consider is a normal consumer-grade USB sensor
+attached to a Linux machine via an RS232 or USB link, reporting to
+<application>gpsd</application> which is polled via sockets by
+application.  Consider the whole transmission path of a PVT
+(position/velocity/time) report from a GPS to the user or user
+application.  It has the following stages:</para>
+
+<orderedlist>
+<listitem>
+<para>A PVT report is generated in the GPS</para>
+</listitem>
+<listitem>
+<para>It is encoded (into NMEA or a vendor binary protocol) 
+and buffered for transmission via serial link.</para>
+</listitem>
+<listitem>
+<para>The encoding is transmitted via serial link to a buffer in GPSD.</para>
+</listitem>
+<listitem>
+<para>The encoding is decoded and translated into a notification in
+GPSD's protocol.</para>
+</listitem>
+<listitem>
+<para>The GPSD-protocol notification is polled and read over a 
+client socket.</para>
+</listitem>
+<listitem>
+<para>The GPSD-protocol notification is decoded by libgps and unpacked
+into a session structure available to the user application.</para>
+</listitem>
+</orderedlist>
+
+<para>It is also relevant that consumer-grade GPses do not expect to
+be polled, but are designed to issue PVT reports on a fixed cycle
+time, which we'll call C and which is usually 1
+second. <application>gpsd</application> expects this.  A few GPSes
+(notably SiRF-II-based ones) can be polled, and we might thus be able
+to pull PVT reports out of them at a higher rate.
+<application>gpsd</application> doesn't do this; one question this
+investigation can address is whether there would be any point to
+that.</para>
+
+<para>At various times GPS manufacturers have promoted proprietary
+binary protocols and transmission speeds higher than the NMEA-standard
+4800bps as ways to improve GPS performance.  Obviously these cannot
+affect positional accuracy; all they can change is the latency at
+stages 2, 3, and 4.</para>
+
+<para>The implementation of <application>gpsd</application> affects
+how much latency is introduced at stage 4.  The design of the
+<application>gpsd</application> protocol (in particular, the average
+and worst-case size and complexity of a position/velocity/time report)
+affects how much latency is introduced at stages 5, 6, and 7.</para>
+
+<para>At stages 5 and later, the client design and implementation 
+matter a lot.  In particular, it matters how frequently the client
+samples the PVT reports that <application>gpsd</application> makes
+available.</para>
+
+<para>The list of stages above implies the following formula for 
+expected latency L, and a set of tactics for reducing it:</para>
+
+<literallayout>
+L = C/2 + E1 + T1 + D1 + W + E2 + T2 + D2
+</literallayout>
+
+<para>where:</para>
+
+<orderedlist>
+<listitem>
+<para>C/2 is the expected delay introduced by a cycle time of C
+(worst-case delay would just be C). We can decrease this by decreasing
+C, but consumer-grade GPSes don't go below 1 second.</para>
+</listitem>
+<listitem>
+<para>E1 is PVT encoding time within the GPS. We can't affect this.</para>
+</listitem>
+<listitem>
+<para>T1 is transmission time over the serial link.  We can decrease
+this by raising the baud rate or increasing the information density 
+of the encoding.</para>
+</listitem>
+<listitem>
+<para>D1 is decode time required for <application>gpsd</application>
+to update its session structure.  We can decrease this, if need be,
+by tuning the implementation or using faster hardware.</para>
+</listitem>
+<listitem>
+<para>W is the wait until the application polls
+<application>gpsd</application>. This can only be reduced by designing
+the application to poll frequently.</para>
+</listitem>
+<listitem>
+<para>E2 is PVT encoding time within the daemon. We can speed this up
+with faster hardware or a simpler GPSD format.</para>
+</listitem>
+<listitem>
+<para>T2 is transmission time over the client socket. Faster hardware,
+a better TCP/IP stack or a denser encoding can decrease this.</para>
+</listitem>
+<listitem>
+<para>D3 is decoding time required for the client library to update
+the session structure visible to the user application.  A simpler 
+GPSD format could decrease this</para>
+</listitem>
+</orderedlist>
+
+<para>The total figure L is of interest, of course.  The first
+question to ask is how it compares to C. But to know where
+tuning this system is worth the effort and where it isn't, the
+relative magnitude of these six components is what is important. In
+particular, if C or E1 dominate, there is no point in trying to tune
+the system at all.</para>
+
+<para>The rule on modern hardware is that computation is cheap,
+communication is expensive.  By this rule, we expect E1, D1, E2, and D2 to
+be small relative to T1 and T2.  We can't predict W.  Thus there is no
+knowing how the sum of the other terms will compare to C, but we know
+that E1 + T1 is the other statistic GPS vendors can easily measure.  C
+&lt; E1 + T1 would be a bad idea, and we can guess that competition among
+GPS vendors will probably tend to push C downwards to the point where
+it's not much larger than E1 + T1.</para>
+
+<para>C is known from manufacturer specifications.
+<application>gpsd</application> and its client libraries can be built
+with profiling code that measures all the other timing variables.  The
+tool
+<citerefentry><refentrytitle>gpsprof</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+collects this data and generates reports and plots from it.  There
+are, however, some sources of error to be aware of:</para>
+
+<itemizedlist>
+<listitem>
+<para>Our way of measuring E1 and T1 is to collect a timestamp on the 
+first character read of a new NMEA sentence, then on the terminating 
+newline, and compare those to the GPS timestamp on the sentence.  
+While this will measure E1+T1 accurately, it will underestimate
+the contribution of T1 to the whole because it doesn't measure
+RS232 activity taking place before the first character becomes
+visible at the receive end.</para>
+</listitem>
+<listitem>
+<para>The $ clause that the daemon uses to ship per-sentence profiling info to
+the client adds substantial bulk to the traffic.  Thus, it will tend 
+to inflate E2, T2, and D2 somewhat.</para>
+</listitem>
+<listitem>
+<para>The client library used for profiling is written in Python,
+which will further inflate D2 relative to the C client library most
+applications are likely to use.</para>
+</listitem>
+<listitem>
+<para>The system-call overhead of profiling (seven
+<citerefentry><refentrytitle>gettimeofday</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+calls per sentence to collect timestamps, several other time-library
+calls per sentence to convert ISO8661 timestamps) will introduce a
+small amount of noise into the figures.  These are cheap calls that
+don't induce disk activity; thus, on modern hardware; we may expect
+the overhead per call to be at worst in the microsecond range.  The
+entire per-sentence overhead system-call overhead should be on the
+order of ten microseconds.</para>
+</listitem>
+</itemizedlist>
+
+</sect1>
+<sect1><title>Data and Analysis</title>
+
+<para>I took measurements using a Haicom 204s USB GPS mouse.  This
+device, using a SiRF-II GPS chipset and PL2303 USB-to-serial chipset, is
+very typical of today's consumer-grade GPS hardware; the Haicom people
+themselves estimated to me in late 2004 that the SirF-II had about 80%
+and rising market share, and the specification sheets I find with
+Web searches back this up. Each profile run used 100 samples.</para>
+
+<para>My host system for the measurements was an Opteron 3400 running an
+"everything" installation of Fedora Core 3.  This is still a
+moderately fast machine in early 2005, but average processor
+utilization remained low throughout the tests.</para>
+
+<para>The version of the GPSD software I used for the test was
+released as 2.13.  It was configured with --enable-profiling.  All
+graphs and figures were generated with
+<citerefentry><refentrytitle>gpsprof</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+a tool built for this purpose and included in the distribution.</para>
+
+<para>One of the effects of building with --enable-profiling is that a 
+form of the B command that normally just reports the RS232 parameters
+can be used to set them (it ships a SiRF-II control string to
+the GPS and then changes the line settings).  I discovered that 
+something in the SiRF-II/PL2303 combination chokes on line speeds
+of 19200 and up.</para>
+
+<para>Another effect is to enable a Z command to switch on profiling.
+When profiling is on, each time 
+<application>gpsd</application>
+reports a fix with timestamp (e.g. on GPGGA, GPMRC and GPGLL
+sentences) it also reports timing information from five checkpoints 
+inside the daemon.  The client library adds two more checkpoints.</para>
+
+<para>Our first graph is with profile reporting turned off, to give us
+a handle on performance with the system disturbed as little as
+possible.  This was generated with <command>gpsprof  -t "Haicom 204s" -T png -f
+uninstrumented -s 4800</command>.  We'll compare it to later plots to
+see the effect of profiling overhead.</para>
+
+<figure><title>Total latency</title>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref='graph1.png'/>
+  </imageobject>
+</mediaobject>
+</figure>
+
+<para>The first thing to notice here is that the fix latency can be
+just over a second; you can see the exact figures in the <ulink
+url='profile1.txt'>raw data</ulink>.  Where is the time going?  Our next
+graph was generated with This was generated with <command>gpsprof  -t
+"Haicom 204s" -T png -f raw -s 4800</command></para>
+
+<figure><title>Instrumented latency report</title>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref='graph2.png'/>
+  </imageobject>
+</mediaobject>
+</figure>
+
+<para>By comparing this graph to the previous one, it is pretty clear
+that the profiling reports are not introducing any measurable latency.
+But what is more interesting is to notice that D1 + W + E2 + T2 + D2
+vanishes &mdash; at this timescale, all we can see is E1 and T1.</para>
+
+<para>The <ulink url='profile2.txt'>raw data</ulink> bears this out.  All
+times besides E1 and T1 are so small that they are comparable to the
+noise level of the measurements.  This may be a bit surprising unless
+one remembers that W=0 is expected in this setup, and that a modern
+zero-copy TCP/IP stack like Linux's implements local sockets with very
+low overhead. It is also a little surprising that E1 is so large
+relative to E1+T1. Recall, however, that this may be measurement
+error.</para>
+
+<para>Our third graph (<command>gpsprof  -t "Haicom 204s" -T
+png -f split -s 4800</command> changes the presentation so we can see
+how latency varies with sentence type.</para>
+
+<figure><title>Split latency report</title>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref='graph3.png'/>
+  </imageobject>
+</mediaobject>
+</figure>
+
+<para>The reason for the comb pattern in the previous graphs is now
+apparent; latency is constant for any given sentence type. The obvious
+correlate would be sentence length &mdash; but looking at the <ulink
+url='profile3.txt'>raw data</ulink>, we see that that is not the only
+factor.  Consider this table:</para>
+
+<informaltable>
+<tgroup cols='3'>
+<thead>
+<row>
+<entry>Sentence type</entry>
+<entry>Typical length</entry>
+<entry>Typical latency</entry>
+</row>
+</thead>
+<tbody>
+<row>
+<entry>GPRMC</entry>
+<entry>70</entry>
+<entry>1.01</entry>
+</row>
+<row>
+<entry>GPGGA</entry>
+<entry>81</entry>
+<entry>0.23</entry>
+</row>
+<row>
+<entry>GPGLL</entry>
+<entry>49</entry>
+<entry>0.31</entry>
+</row>
+</tbody>
+</tgroup>
+</informaltable>
+
+<para>For illustration, here are some sample NMEA sentences logged 
+while I was conducting these tests:</para>
+
+<literallayout>
+$GPRMC,183424.834,A,4002.1033,N,07531.2003,W,0.00,0.00,170205,,*11
+$GPGGA,183425.834,4002.1035,N,07531.2004,W,1,05,1.9,134.7,M,-33.8,M,0.0,0000*48
+$GPGLL,4002.1035,N,07531.2004,W,183425.834,A*27
+</literallayout>
+
+<para>Though GPRMCs are shorter than GPGAs, they consistently have an
+associated latency four times as long.  The graph tells us most of
+this is E1.  There must be something the GPS is doing that is
+computationally very expensive when it generates GPRMCs.  It may well
+be that it is actually doing that fix at that point in the send cycle
+and buffering the results for retransmission in GPGGA and GPGLL forms.
+Alternatively, perhaps the speed/track computation is
+expensive.</para>
+
+<para>Now let's look at how the picture changes when we double the
+baud rate.  <command>gpsprof -t "Haicom 204s" -T png -s 9600</command>
+gives us this:</para>
+
+<figure><title>Split latency report, 9600bps</title>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref='graph4.png'/>
+  </imageobject>
+</mediaobject>
+</figure>
+
+<para>This graph looks almost identical to the previous one, except
+for vertical scale &mdash; latency has been cut neatly in half.
+Transmission times for GPMRC go from about 0.15sec to 0.75sec. Oddly,
+average E1 is also cut almost in half.  I don't know how to explain
+this, unless a, lot of what looks like E1 is actually RS232
+transmission time spent before the first character appears in the
+daemon's receive buffers.  You can also view the 
+<ulink url='profile4.txt'>raw data</ulink></para>
+
+<para>For comparison, here's the same plot made with a BU303b, a
+different USB GPS mouse using the same SiRF-II/PL2303 combination:</para>
+
+<figure><title>Split latency report, 9600bps</title>
+<mediaobject>
+  <imageobject>
+    <imagedata fileref='graph5.png'/>
+  </imageobject>
+</mediaobject>
+</figure>
+
+<para>This, and the <ulink url='profile5.txt'>raw data</ulink>, look
+very similar to the Haicom numbers.  The main difference seems to be
+that the BU303b firmware doesn't ship GPGLL by default.</para>
+
+</sect1>
+<sect1><title>Conclusions</title>
+
+<para>All these conclusions apply to the consumer-grade GPS hardware 
+generally available in 2005, e.g. with a C of one second.</para>
+
+<sect2><title>For Application Programmers</title>
+
+<para>For the best tradeoff between minimizing latency and use of
+application resources, Nyquist's Theorem tells us to poll
+<application>gpsd</application> once every half-cycle &mdash; that is,
+on almost all GPSes at time of writing, twice a second.</para>
+
+<para>With the SiRF-II chips used in most consumer-grade GPSes at time of
+writing, 9600bps is the optimal line speed.  4800 is slightly too low,
+not guaranteeing updates within the 1-second cycle time.  9600bps
+yields updates in about 0.5sec.</para>
+
+</sect2>
+<sect2><title>For Manufacturer Claims</title>
+
+<para>At the 1-second cycle time of consumer-grade devices, being able
+to operate at 9600bps is useful, but higher speeds would not be worth
+the effort.</para>
+
+<para>Comparing the SiRF-II performance at 4800bps and 9600 shows a
+drop in E1+T1 that looks about linear, suggesting that for a cycle of
+n seconds, the optimal line speed would be about 9600/n. Since future
+GPS chips are likely to have faster processors and thus less latency,
+this may be considered an upper bound on useful line speed.</para>
+
+<para>Because 9600bps is readily available, the transmission- and
+decode-time advantages of binary protocols over NMEA are not
+significant within a 1-per-second update cycle.  Because line speeds
+up to 38400 are readily available through standard UARTs, we may
+expect this to continue to be the case even with cycle times as
+low as 0.25sec.</para>
+
+<para>More generally, binary protocols are largely pointless except as
+market-control devices for the the manufacturers.  The additional
+capabilities they support could be just as effectively supported
+through NMEA's $P-prefix extension mechanism.</para>
+
+</sect2>
+<sect2><title>For the Design of <application>gpsd</application></title>
+
+<para><application>gpsd</application> does not introduce measurable 
+latency into the path from GPS to application.  Cycle times would 
+have to decrease by two orders of magnitude for this to change.</para>
+
+<para>Setting a 9600bps line speed, and then polling the GPS twice a 
+second rather than waiting for an update, would halve the expected 
+latency of the system from 0.5 to 0.25sec. This would be right at the
+edge of the SiRF-II's performance envelope.</para>
+
+</sect2>
+</sect1>
+</article>
+
+<!--
+Local Variables:
+compile-command: "xmlto xhtml-nochunks performance.xml"
+End:
+-->
diff --git a/www/performance/profile1.txt b/www/performance/profile1.txt
new file mode 100644
index 00000000..abd57eff
--- /dev/null
+++ b/www/performance/profile1.txt
@@ -0,0 +1,101 @@
+# Uninstrumented total latency, Haicom 204s, 4800N1, cycle 1s
+1.023544
+0.216441
+0.328521
+1.014338
+0.218396
+0.330239
+1.015195
+0.217151
+0.329242
+1.014043
+0.218018
+0.331103
+1.014912
+0.218858
+0.330814
+1.015768
+0.218726
+0.330656
+1.014628
+0.217569
+0.329597
+1.014489
+0.219423
+0.331382
+1.017343
+0.218288
+0.330230
+1.015204
+0.218140
+0.330093
+1.015062
+0.218026
+0.329950
+1.014920
+0.217866
+0.329804
+1.014778
+0.218399
+0.329669
+1.014649
+0.216587
+0.329547
+1.013621
+0.217451
+0.329379
+1.014595
+0.217313
+0.329242
+1.014322
+0.217170
+0.330095
+1.014103
+0.220021
+0.331948
+1.017168
+0.216968
+0.328808
+1.013795
+0.217733
+0.329671
+1.014644
+0.217747
+0.329588
+1.015501
+0.220539
+0.332400
+1.017363
+0.218310
+0.330246
+1.015243
+0.217174
+0.330103
+1.014075
+0.218030
+0.329970
+1.014937
+0.220887
+0.332820
+1.017795
+0.216746
+0.329681
+1.013685
+0.220602
+0.332550
+1.017514
+0.218465
+0.331394
+1.015367
+0.222329
+0.335256
+1.019225
+0.218169
+0.330136
+1.015086
+0.218043
+0.330045
+1.014940
+0.218888
+0.330904
+1.015802
diff --git a/www/performance/profile2.txt b/www/performance/profile2.txt
new file mode 100644
index 00000000..a64cb9b3
--- /dev/null
+++ b/www/performance/profile2.txt
@@ -0,0 +1,103 @@
+# Raw latency data, Haicom 204s, 4800N1, cycle 1s
+#	      T1	      E1	      D1	       W	      E2	      T2	      D2	tag
+#-	--------	--------	--------	--------	--------	--------	--------	--------
+69	0.864900	1.018900	1.019400	1.019400	1.019500	1.019593	1.019731  	# GPRMC
+82	0.033900	0.216800	0.217400	0.217400	0.217400	0.217559	0.217680  	# GPGGA
+49	0.222000	0.328800	0.329400	0.329400	0.329400	0.329537	0.329626  	# GPGLL
+69	0.860800	1.013700	1.014300	1.014300	1.014300	1.014449	1.014584  	# GPRMC
+82	0.033700	0.216700	0.217300	0.217300	0.217300	0.217420	0.217540  	# GPGGA
+49	0.221700	0.328700	0.329200	0.329200	0.329300	0.329390	0.329479  	# GPGLL
+69	0.860700	1.013600	1.014200	1.014200	1.014200	1.014310	1.014447  	# GPRMC
+82	0.033600	0.216600	0.217100	0.217100	0.217100	0.217284	0.217406  	# GPGGA
+49	0.220600	0.329500	0.330100	0.330100	0.330100	0.330258	0.330350  	# GPGLL
+69	0.860500	1.014400	1.015000	1.015000	1.015000	1.015165	1.015304  	# GPRMC
+82	0.035500	0.218400	0.219000	0.219000	0.219000	0.219163	0.219283  	# GPGGA
+49	0.223400	0.330400	0.331000	0.331000	0.331000	0.331112	0.331201  	# GPGLL
+69	0.862300	1.015300	1.015900	1.015900	1.015900	1.016027	1.016163  	# GPRMC
+82	0.035300	0.218300	0.218800	0.218800	0.218900	0.219001	0.219119  	# GPGGA
+49	0.223300	0.330300	0.330800	0.330900	0.330900	0.331062	0.331152  	# GPGLL
+69	0.862200	1.015200	1.015700	1.015700	1.015700	1.015880	1.016016  	# GPRMC
+82	0.035200	0.218100	0.218700	0.218700	0.218700	0.218854	0.218973  	# GPGGA
+49	0.222300	0.330100	0.330700	0.330700	0.330700	0.330825	0.330917  	# GPGLL
+69	0.861000	1.015000	1.015600	1.015600	1.015600	1.015767	1.015905  	# GPRMC
+82	0.034000	0.218000	0.218600	0.218600	0.218600	0.218717	0.218838  	# GPGGA
+49	0.222000	0.330000	0.330500	0.330500	0.330600	0.330693	0.330784  	# GPGLL
+69	0.860900	1.014900	1.015500	1.015500	1.015500	1.015625	1.015763  	# GPRMC
+82	0.033900	0.216900	0.217400	0.217400	0.217400	0.217568	0.217695  	# GPGGA
+49	0.221900	0.328900	0.329400	0.329400	0.329400	0.329636	0.329722  	# GPGLL
+69	0.859800	1.013700	1.014300	1.014300	1.014300	1.014450	1.014585  	# GPRMC
+82	0.033800	0.216700	0.217300	0.217300	0.217300	0.217451	0.217571  	# GPGGA
+49	0.221900	0.328700	0.329200	0.329200	0.329300	0.329399	0.329515  	# GPGLL
+69	0.859600	1.014600	1.015200	1.015200	1.015200	1.015311	1.015449  	# GPRMC
+82	0.034600	0.217600	0.218100	0.218100	0.218200	0.218294	0.218414  	# GPGGA
+49	0.222600	0.329600	0.330100	0.330100	0.330100	0.330258	0.330349  	# GPGLL
+69	0.861500	1.014500	1.015000	1.015000	1.015000	1.015170	1.015306  	# GPRMC
+82	0.035500	0.218500	0.219000	0.219000	0.219100	0.219186	0.219307  	# GPGGA
+49	0.222400	0.330400	0.331000	0.331000	0.331000	0.331115	0.331204  	# GPGLL
+69	0.861300	1.015300	1.015900	1.015900	1.015900	1.016035	1.016169  	# GPRMC
+82	0.034300	0.217300	0.217900	0.217900	0.217900	0.218039	0.218160  	# GPGGA
+49	0.222300	0.329300	0.329800	0.329800	0.329800	0.329968	0.330059  	# GPGLL
+69	0.861200	1.014200	1.014700	1.014700	1.014800	1.014891	1.015027  	# GPRMC
+82	0.034200	0.217100	0.217700	0.217700	0.217800	0.217889	0.218009  	# GPGGA
+49	0.222200	0.329100	0.329700	0.329700	0.329700	0.329831	0.329920  	# GPGLL
+69	0.861100	1.014000	1.014600	1.014600	1.014600	1.014752	1.014890  	# GPRMC
+82	0.036000	0.219000	0.219600	0.219600	0.219600	0.219715	0.219835  	# GPGGA
+49	0.224000	0.331000	0.331500	0.331500	0.331600	0.331697	0.331785  	# GPGLL
+69	0.862900	1.015900	1.016400	1.016500	1.016500	1.016609	1.016744  	# GPRMC
+82	0.032900	0.216900	0.217400	0.217400	0.217400	0.217574	0.217692  	# GPGGA
+49	0.220900	0.328800	0.329400	0.329400	0.329400	0.329555	0.329646  	# GPGLL
+69	0.859800	1.012700	1.013300	1.013300	1.013300	1.013462	1.013598  	# GPRMC
+82	0.033700	0.216700	0.217300	0.217300	0.217300	0.217434	0.217552  	# GPGGA
+49	0.221700	0.328700	0.329200	0.329300	0.329300	0.329427	0.329518  	# GPGLL
+69	0.861600	1.014600	1.015200	1.015200	1.015200	1.015318	1.015453  	# GPRMC
+82	0.033600	0.216600	0.217100	0.217100	0.217200	0.217294	0.217413  	# GPGGA
+49	0.221700	0.328600	0.329100	0.329100	0.329100	0.329259	0.329350  	# GPGLL
+69	0.860500	1.013500	1.014100	1.014100	1.014100	1.014291	1.014427  	# GPRMC
+82	0.034500	0.217500	0.218000	0.218100	0.218100	0.218212	0.218332  	# GPGGA
+49	0.221400	0.329400	0.330000	0.330000	0.330000	0.330120	0.330212  	# GPGLL
+69	0.860300	1.014300	1.014900	1.014900	1.014900	1.015047	1.015183  	# GPRMC
+82	0.034300	0.217300	0.217900	0.217900	0.217900	0.218128	0.218247  	# GPGGA
+49	0.221300	0.329400	0.329900	0.329900	0.329900	0.330135	0.330224  	# GPGLL
+69	0.860200	1.014200	1.014700	1.014700	1.014800	1.014895	1.015031  	# GPRMC
+82	0.034200	0.218100	0.218700	0.218700	0.218800	0.218898	0.219016  	# GPGGA
+49	0.222200	0.330100	0.330700	0.330700	0.330700	0.330828	0.330915  	# GPGLL
+69	0.861100	1.015000	1.015600	1.015600	1.015600	1.015759	1.015893  	# GPRMC
+82	0.034000	0.217000	0.217600	0.217600	0.217600	0.217718	0.217836  	# GPGGA
+49	0.221000	0.329000	0.329600	0.329600	0.329600	0.329735	0.329825  	# GPGLL
+69	0.859900	1.013900	1.014500	1.014500	1.014500	1.014639	1.014773  	# GPRMC
+81	0.029900	0.210900	0.211500	0.211500	0.211500	0.211617	0.211737  	# GPGGA
+49	0.215900	0.322900	0.323400	0.323400	0.323400	0.323544	0.323631  	# GPGLL
+69	0.842800	0.996800	0.997400	0.997400	0.997400	0.997524	0.997661  	# GPRMC
+81	0.026900	0.207800	0.208300	0.208300	0.208300	0.208474	0.208593  	# GPGGA
+49	0.212800	0.319700	0.320300	0.320300	0.320300	0.320407	0.320522  	# GPGLL
+69	0.839600	0.993600	0.994200	0.994200	0.994200	0.994335	0.994472  	# GPRMC
+81	0.026600	0.207600	0.208100	0.208100	0.208200	0.208301	0.208422  	# GPGGA
+49	0.212600	0.319600	0.320100	0.320100	0.320100	0.320258	0.320347  	# GPGLL
+69	0.839600	0.993500	0.994000	0.994000	0.994100	0.994198	0.994335  	# GPRMC
+81	0.029500	0.210400	0.211000	0.211000	0.211000	0.211171	0.211292  	# GPGGA
+49	0.214500	0.322400	0.323000	0.323000	0.323000	0.323125	0.323212  	# GPGLL
+69	0.842400	0.995300	0.995900	0.995900	0.995900	0.996053	0.996189  	# GPRMC
+81	0.027300	0.208400	0.208900	0.208900	0.209000	0.209180	0.209311  	# GPGGA
+49	0.212300	0.320300	0.320900	0.320900	0.320900	0.321009	0.321097  	# GPGLL
+69	0.840300	0.993200	0.993700	0.993700	0.993800	0.993906	0.994042  	# GPRMC
+81	0.026200	0.207200	0.207700	0.207700	0.207700	0.207877	0.207999  	# GPGGA
+49	0.212200	0.319100	0.319700	0.319700	0.319700	0.319834	0.319922  	# GPGLL
+69	0.839100	0.993200	0.993700	0.993800	0.993800	0.993965	0.994114  	# GPRMC
+81	0.026100	0.207000	0.207600	0.207600	0.207600	0.207733	0.207854  	# GPGGA
+49	0.212000	0.320000	0.320600	0.320600	0.320600	0.320707	0.320795  	# GPGLL
+69	0.839000	0.992900	0.993500	0.993500	0.993500	0.993625	0.993762  	# GPRMC
+81	0.025900	0.206900	0.207400	0.207400	0.207500	0.207590	0.207709  	# GPGGA
+49	0.210900	0.319300	0.319900	0.319900	0.319900	0.320362	0.320450  	# GPGLL
+69	0.839900	0.992800	0.993300	0.993300	0.993300	0.993478	0.993614  	# GPRMC
+81	0.028800	0.209800	0.210300	0.210300	0.210300	0.210483	0.210603  	# GPGGA
+49	0.213700	0.321800	0.322400	0.322400	0.322400	0.322617	0.322723  	# GPGLL
+69	0.841600	0.994600	0.995200	0.995200	0.995200	0.995344	0.995480  	# GPRMC
+81	0.029600	0.209600	0.210100	0.210100	0.210200	0.210303	0.210424  	# GPGGA
+49	0.214600	0.322600	0.323100	0.323100	0.323200	0.323294	0.323381  	# GPGLL
+69	0.842500	0.995500	0.996000	0.996000	0.996100	0.996195	0.996332  	# GPRMC
+81	0.026500	0.207400	0.208000	0.208000	0.208000	0.208163	0.208283  	# GPGGA
+49	0.212500	0.319400	0.320000	0.320000	0.320000	0.320136	0.320225  	# GPGLL
+69	0.839400	0.993300	0.993900	0.993900	0.993900	0.994054	0.994191  	# GPRMC
+81	0.028300	0.209300	0.209900	0.209900	0.209900	0.210037	0.210158  	# GPGGA
+49	0.213300	0.321400	0.321900	0.321900	0.322000	0.322088	0.322175  	# GPGLL
+69	0.841200	0.994200	0.994800	0.994800	0.994800	0.994924	0.995058  	# GPRMC
diff --git a/www/performance/profile3.txt b/www/performance/profile3.txt
new file mode 100644
index 00000000..8b13681c
--- /dev/null
+++ b/www/performance/profile3.txt
@@ -0,0 +1,103 @@
+# Split latency data, Haicom 204s, 4800N1, cycle 1s
+#   GPGGA	   GPRMC	   GPGLL	      T1	      D1	       W	      E2	      T2	      D2	  length	tag
+# ---------	---------	---------	---------	---------	---------	---------	---------	---------	---------	--------
+-       	0.874600	-       	1.019000	1.019600	1.019600	1.019600	1.019769	1.019908	      70	# GPRMC
+0.034000	-       	-       	0.215000	0.215600	0.215600	0.215600	0.215717	0.215837	      81	# GPGGA
+-       	-       	0.220000	0.327100	0.327600	0.327700	0.327700	0.327946	0.328045	      49	# GPGLL
+-       	0.855900	-       	1.011900	1.012400	1.012500	1.012500	1.012609	1.012745	      70	# GPRMC
+0.033900	-       	-       	0.214900	0.215500	0.215500	0.215500	0.215645	0.215766	      81	# GPGGA
+-       	-       	0.219900	0.326900	0.327400	0.327400	0.327400	0.327583	0.327672	      49	# GPGLL
+-       	0.855800	-       	1.011700	1.012300	1.012300	1.012300	1.012467	1.012602	      70	# GPRMC
+0.033000	-       	-       	0.213700	0.214300	0.214300	0.214300	0.214432	0.214553	      81	# GPGGA
+-       	-       	0.218700	0.326700	0.327300	0.327300	0.327300	0.327515	0.327604	      49	# GPGLL
+-       	0.855600	-       	1.010600	1.011200	1.011200	1.011200	1.011331	1.011466	      70	# GPRMC
+0.032700	-       	-       	0.213600	0.214100	0.214200	0.214200	0.214310	0.214430	      81	# GPGGA
+-       	-       	0.218600	0.330200	0.330700	0.330700	0.330800	0.331253	0.331340	      49	# GPGLL
+-       	0.855500	-       	1.011500	1.012000	1.012000	1.012000	1.012184	1.012322	      70	# GPRMC
+0.033500	-       	-       	0.214400	0.215000	0.215000	0.215000	0.215154	0.215273	      81	# GPGGA
+-       	-       	0.219500	0.327400	0.328000	0.328000	0.328000	0.328143	0.328232	      49	# GPGLL
+-       	0.857400	-       	1.011300	1.011900	1.011900	1.011900	1.012046	1.012181	      70	# GPRMC
+0.034400	-       	-       	0.215300	0.215800	0.215800	0.215900	0.216003	0.216125	      81	# GPGGA
+-       	-       	0.219300	0.327300	0.327800	0.327800	0.327800	0.327973	0.328061	      49	# GPGLL
+-       	0.856200	-       	1.012200	1.012700	1.012700	1.012800	1.012892	1.013027	      70	# GPRMC
+0.039200	-       	-       	0.219100	0.219700	0.219700	0.219700	0.219858	0.219979	      81	# GPGGA
+-       	-       	0.224100	0.332500	0.333100	0.333100	0.333100	0.333255	0.333346	      49	# GPGLL
+-       	0.861100	-       	1.016000	1.016600	1.016600	1.016600	1.016745	1.016884	      70	# GPRMC
+0.035000	-       	-       	0.216000	0.216500	0.216600	0.216600	0.216712	0.216833	      81	# GPGGA
+-       	-       	0.220100	0.328000	0.328500	0.328500	0.328600	0.328688	0.328777	      49	# GPGLL
+-       	0.856900	-       	1.012900	1.013500	1.013500	1.013500	1.013670	1.013807	      70	# GPRMC
+0.033900	-       	-       	0.214800	0.215400	0.215400	0.215400	0.215564	0.215685	      81	# GPGGA
+-       	-       	0.219900	0.327800	0.328400	0.328400	0.328400	0.328541	0.328629	      49	# GPGLL
+-       	0.856800	-       	1.011700	1.012300	1.012300	1.012300	1.012475	1.012611	      70	# GPRMC
+0.036700	-       	-       	0.216700	0.217300	0.217300	0.217300	0.217548	0.217668	      81	# GPGGA
+-       	-       	0.221700	0.329700	0.330300	0.330300	0.330300	0.330431	0.330519	      49	# GPGLL
+-       	0.858600	-       	1.013600	1.014100	1.014100	1.014200	1.014309	1.014446	      70	# GPRMC
+0.035600	-       	-       	0.216600	0.217100	0.217100	0.217100	0.217281	0.217402	      81	# GPGGA
+-       	-       	0.221600	0.328500	0.329100	0.329100	0.329100	0.329255	0.329345	      49	# GPGLL
+-       	0.858500	-       	1.014400	1.015000	1.015000	1.015000	1.015162	1.015298	      70	# GPRMC
+0.034500	-       	-       	0.215400	0.216000	0.216000	0.216000	0.216134	0.216255	      81	# GPGGA
+-       	-       	0.220400	0.327400	0.327900	0.328000	0.328000	0.328107	0.328196	      49	# GPGLL
+-       	0.856300	-       	1.012300	1.012900	1.012900	1.012900	1.013018	1.013154	      70	# GPRMC
+0.036300	-       	-       	0.217300	0.217800	0.217800	0.217900	0.217986	0.218106	      81	# GPGGA
+-       	-       	0.221300	0.329300	0.329800	0.329800	0.329800	0.329961	0.330052	      49	# GPGLL
+-       	0.858200	-       	1.014200	1.014700	1.014700	1.014700	1.014873	1.015011	      70	# GPRMC
+0.034200	-       	-       	0.215100	0.215700	0.215700	0.215700	0.215849	0.215970	      81	# GPGGA
+-       	-       	0.220200	0.327100	0.327700	0.327700	0.327700	0.327837	0.327927	      49	# GPGLL
+-       	0.856000	-       	1.012000	1.012600	1.012600	1.012600	1.012744	1.012880	      70	# GPRMC
+0.034100	-       	-       	0.215100	0.215700	0.215700	0.215700	0.215889	0.216023	      81	# GPGGA
+-       	-       	0.220000	0.327000	0.327600	0.327600	0.327600	0.327723	0.327809	      49	# GPGLL
+-       	0.855900	-       	1.011900	1.012400	1.012400	1.012500	1.012593	1.012730	      70	# GPRMC
+0.033900	-       	-       	0.215000	0.215500	0.215600	0.215600	0.215754	0.215893	      81	# GPGGA
+-       	-       	0.218800	0.326800	0.327400	0.327400	0.327400	0.327544	0.327633	      49	# GPGLL
+-       	0.855700	-       	1.010700	1.011300	1.011300	1.011300	1.011447	1.011583	      70	# GPRMC
+0.033700	-       	-       	0.213700	0.214200	0.214300	0.214300	0.214412	0.214533	      81	# GPGGA
+-       	-       	0.218700	0.326700	0.327200	0.327200	0.327300	0.327398	0.327486	      49	# GPGLL
+-       	0.855600	-       	1.010700	1.011200	1.011200	1.011200	1.011434	1.011583	      70	# GPRMC
+0.033600	-       	-       	0.215600	0.216100	0.216100	0.216100	0.216275	0.216396	      81	# GPGGA
+-       	-       	0.219800	0.327500	0.328100	0.328100	0.328100	0.328245	0.328333	      49	# GPGLL
+-       	0.856500	-       	1.012400	1.013000	1.013000	1.013000	1.013286	1.013432	      70	# GPRMC
+0.033500	-       	-       	0.214400	0.215000	0.215000	0.215000	0.215120	0.215240	      81	# GPGGA
+-       	-       	0.219400	0.326400	0.326900	0.326900	0.327000	0.327106	0.327196	      49	# GPGLL
+-       	0.855300	-       	1.011300	1.011900	1.011900	1.011900	1.012014	1.012151	      70	# GPRMC
+0.034400	-       	-       	0.215500	0.216000	0.216000	0.216000	0.216169	0.216303	      81	# GPGGA
+-       	-       	0.219300	0.327300	0.327800	0.327800	0.327800	0.327978	0.328066	      49	# GPGLL
+-       	0.856200	-       	1.012300	1.012900	1.012900	1.012900	1.013186	1.013321	      70	# GPRMC
+0.034200	-       	-       	0.215100	0.215700	0.215700	0.215700	0.215840	0.215961	      81	# GPGGA
+-       	-       	0.219100	0.327100	0.327700	0.327700	0.327700	0.327808	0.327895	      49	# GPGLL
+-       	0.856000	-       	1.012100	1.012700	1.012700	1.012700	1.012908	1.013059	      70	# GPRMC
+0.034000	-       	-       	0.215000	0.215500	0.215500	0.215600	0.215699	0.215834	      81	# GPGGA
+-       	-       	0.219000	0.327200	0.327700	0.327700	0.327800	0.327900	0.328001	      49	# GPGLL
+-       	0.855900	-       	1.010900	1.011400	1.011400	1.011400	1.011579	1.011715	      70	# GPRMC
+0.032900	-       	-       	0.213900	0.214400	0.214400	0.214400	0.214583	0.214705	      81	# GPGGA
+-       	-       	0.217800	0.325800	0.326400	0.326400	0.326400	0.326527	0.326616	      49	# GPGLL
+-       	0.854700	-       	1.010700	1.011300	1.011300	1.011300	1.011438	1.011574	      70	# GPRMC
+0.033700	-       	-       	0.214700	0.215200	0.215300	0.215300	0.215411	0.215532	      81	# GPGGA
+-       	-       	0.219800	0.326700	0.327200	0.327200	0.327300	0.327384	0.327471	      49	# GPGLL
+-       	0.856600	-       	1.012600	1.013100	1.013100	1.013200	1.013299	1.013435	      70	# GPRMC
+0.034600	-       	-       	0.215500	0.216100	0.216100	0.216100	0.216285	0.216407	      81	# GPGGA
+-       	-       	0.219500	0.327500	0.328100	0.328100	0.328100	0.328243	0.328332	      49	# GPGLL
+-       	0.856500	-       	1.012400	1.013000	1.013000	1.013000	1.013149	1.013285	      70	# GPRMC
+0.034500	-       	-       	0.215400	0.216000	0.216000	0.216000	0.216119	0.216240	      81	# GPGGA
+-       	-       	0.219400	0.327400	0.327900	0.327900	0.328000	0.328098	0.328190	      49	# GPGLL
+-       	0.856300	-       	1.012300	1.012800	1.012900	1.012900	1.013011	1.013149	      70	# GPRMC
+0.034300	-       	-       	0.215300	0.215800	0.215800	0.215800	0.215972	0.216093	      81	# GPGGA
+-       	-       	0.220300	0.328200	0.328800	0.328800	0.328800	0.328947	0.329035	      49	# GPGLL
+-       	0.857200	-       	1.012200	1.012800	1.012800	1.012800	1.012931	1.013067	      70	# GPRMC
+0.034200	-       	-       	0.215100	0.215700	0.215700	0.215700	0.215830	0.215951	      81	# GPGGA
+-       	-       	0.220100	0.327100	0.327600	0.327600	0.327700	0.327801	0.327888	      49	# GPGLL
+-       	0.856000	-       	1.012000	1.012600	1.012600	1.012600	1.012714	1.012850	      70	# GPRMC
+0.034100	-       	-       	0.214200	0.214800	0.214800	0.214800	0.214975	0.215096	      81	# GPGGA
+-       	-       	0.219000	0.326900	0.327500	0.327500	0.327500	0.327666	0.327755	      49	# GPGLL
+-       	0.855900	-       	1.010900	1.011400	1.011400	1.011400	1.011584	1.011721	      70	# GPRMC
+0.035900	-       	-       	0.216800	0.217400	0.217400	0.217400	0.217567	0.217688	      81	# GPGGA
+-       	-       	0.221800	0.329800	0.330400	0.330400	0.330400	0.330515	0.330602	      49	# GPGLL
+-       	0.858700	-       	1.013700	1.014300	1.014300	1.014300	1.014424	1.014560	      70	# GPRMC
+0.032800	-       	-       	0.214700	0.215200	0.215200	0.215300	0.215398	0.215519	      81	# GPGGA
+-       	-       	0.219800	0.327700	0.328200	0.328200	0.328200	0.328381	0.328469	      49	# GPGLL
+-       	0.856600	-       	1.011600	1.012100	1.012100	1.012200	1.012288	1.012424	      70	# GPRMC
+0.033600	-       	-       	0.214500	0.215100	0.215100	0.215100	0.215252	0.215372	      81	# GPGGA
+-       	-       	0.219600	0.327600	0.328100	0.328200	0.328200	0.328305	0.328393	      49	# GPGLL
+-       	0.856500	-       	1.009400	1.010000	1.010000	1.010000	1.010142	1.010278	      69	# GPRMC
+0.034500	-       	-       	0.215400	0.215900	0.215900	0.216000	0.216106	0.216227	      81	# GPGGA
+-       	-       	0.219500	0.327400	0.327900	0.327900	0.328000	0.328090	0.328186	      49	# GPGLL
+-       	0.856600	-       	1.009300	1.009900	1.009900	1.009900	1.010061	1.010197	      69	# GPRMC
diff --git a/www/performance/profile4.txt b/www/performance/profile4.txt
new file mode 100644
index 00000000..5aa981be
--- /dev/null
+++ b/www/performance/profile4.txt
@@ -0,0 +1,103 @@
+# Split latency data, Haicom 204s, 9600N1, cycle 1s
+#   GPGGA	   GPRMC	   GPGLL	      T1	      D1	       W	      E2	      T2	      D2	  length	tag
+# ---------	---------	---------	---------	---------	---------	---------	---------	---------	---------	--------
+-       	0.420500	-       	0.498200	0.498800	0.498800	0.498800	0.498942	0.499078	      70	# GPRMC
+0.022200	-       	-       	0.113100	0.113700	0.113700	0.113700	0.113839	0.113967	      82	# GPGGA
+-       	-       	0.115100	0.169100	0.169700	0.169700	0.169700	0.169891	0.170010	      49	# GPGLL
+-       	0.420100	-       	0.497100	0.497600	0.497600	0.497700	0.497783	0.497914	      70	# GPRMC
+0.021000	-       	-       	0.113000	0.113500	0.113500	0.113600	0.113693	0.113810	      82	# GPGGA
+-       	-       	0.115200	0.169000	0.169500	0.169600	0.169600	0.169702	0.169789	      49	# GPGLL
+-       	0.420200	-       	0.497900	0.498500	0.498500	0.498500	0.498651	0.498783	      70	# GPRMC
+0.022900	-       	-       	0.113800	0.114400	0.114400	0.114400	0.114563	0.114679	      82	# GPGGA
+-       	-       	0.117200	0.169900	0.170400	0.170400	0.170400	0.170572	0.170660	      49	# GPGLL
+-       	0.420800	-       	0.497800	0.498300	0.498400	0.498400	0.498508	0.498640	      70	# GPRMC
+0.022700	-       	-       	0.113700	0.114300	0.114300	0.114300	0.114419	0.114537	      82	# GPGGA
+-       	-       	0.115700	0.169700	0.170300	0.170300	0.170300	0.170467	0.170555	      49	# GPGLL
+-       	0.419900	-       	0.497600	0.498200	0.498200	0.498200	0.498363	0.498503	      70	# GPRMC
+0.022600	-       	-       	0.113600	0.114100	0.114100	0.114100	0.114274	0.114391	      82	# GPGGA
+-       	-       	0.115800	0.169600	0.170100	0.170100	0.170100	0.170277	0.170364	      49	# GPGLL
+-       	0.419800	-       	0.497500	0.498100	0.498100	0.498100	0.498218	0.498349	      70	# GPRMC
+0.022400	-       	-       	0.114400	0.115000	0.115000	0.115000	0.115132	0.115250	      82	# GPGGA
+-       	-       	0.116400	0.170400	0.171000	0.171000	0.171000	0.171139	0.171228	      49	# GPGLL
+-       	0.420600	-       	0.498400	0.498900	0.498900	0.499000	0.499089	0.499221	      70	# GPRMC
+0.025300	-       	-       	0.117300	0.117800	0.117800	0.117800	0.117979	0.118106	      82	# GPGGA
+-       	-       	0.119500	0.173300	0.173800	0.173800	0.173800	0.173956	0.174053	      49	# GPGLL
+-       	0.423500	-       	0.501200	0.501800	0.501800	0.501800	0.501954	0.502095	      70	# GPRMC
+0.022200	-       	-       	0.114100	0.114700	0.114700	0.114700	0.114836	0.114953	      82	# GPGGA
+-       	-       	0.116400	0.170100	0.170700	0.170700	0.170700	0.170814	0.170901	      49	# GPGLL
+-       	0.420300	-       	0.498100	0.498600	0.498600	0.498700	0.498781	0.498914	      70	# GPRMC
+0.023000	-       	-       	0.115000	0.115600	0.115600	0.115600	0.115722	0.115840	      82	# GPGGA
+-       	-       	0.117000	0.171000	0.171500	0.171500	0.171600	0.171681	0.171769	      49	# GPGLL
+-       	0.421200	-       	0.498900	0.499500	0.499500	0.499500	0.499662	0.499796	      70	# GPRMC
+0.028900	-       	-       	0.118800	0.119400	0.119400	0.119400	0.119562	0.119679	      81	# GPGGA
+-       	-       	0.120800	0.174800	0.175400	0.175400	0.175400	0.175537	0.175625	      49	# GPGLL
+-       	0.425100	-       	0.502800	0.503400	0.503400	0.503400	0.503565	0.503696	      70	# GPRMC
+0.026700	-       	-       	0.117700	0.118300	0.118300	0.118300	0.118417	0.118535	      81	# GPGGA
+-       	-       	0.120000	0.173700	0.174300	0.174300	0.174300	0.174417	0.174503	      49	# GPGLL
+-       	0.423900	-       	0.501600	0.502200	0.502200	0.502300	0.502387	0.502519	      70	# GPRMC
+0.027700	-       	-       	0.117600	0.118100	0.118100	0.118100	0.118275	0.118416	      81	# GPGGA
+-       	-       	0.119600	0.173600	0.174100	0.174100	0.174200	0.174280	0.174367	      49	# GPGLL
+-       	0.423800	-       	0.501500	0.502100	0.502100	0.502100	0.502223	0.502356	      70	# GPRMC
+0.027400	-       	-       	0.117400	0.118000	0.118000	0.118000	0.118136	0.118254	      81	# GPGGA
+-       	-       	0.119400	0.173400	0.174000	0.174000	0.174000	0.174186	0.174272	      49	# GPGLL
+-       	0.423700	-       	0.501400	0.501900	0.501900	0.501900	0.502079	0.502211	      70	# GPRMC
+0.027300	-       	-       	0.117300	0.117800	0.117800	0.117900	0.117985	0.118111	      81	# GPGGA
+-       	-       	0.119300	0.173300	0.173800	0.173800	0.173900	0.173983	0.174079	      49	# GPGLL
+-       	0.423500	-       	0.501200	0.501800	0.501800	0.501800	0.501928	0.502060	      70	# GPRMC
+0.026200	-       	-       	0.116100	0.116700	0.116700	0.116700	0.116845	0.116961	      81	# GPGGA
+-       	-       	0.119500	0.172100	0.172700	0.172700	0.172700	0.172819	0.172907	      49	# GPGLL
+-       	0.424100	-       	0.501100	0.501600	0.501600	0.501700	0.501787	0.501919	      70	# GPRMC
+0.027000	-       	-       	0.117000	0.117500	0.117600	0.117600	0.117705	0.117823	      81	# GPGGA
+-       	-       	0.120000	0.173000	0.173500	0.173500	0.173600	0.173685	0.173772	      49	# GPGLL
+-       	0.424000	-       	0.500900	0.501500	0.501500	0.501500	0.501641	0.501772	      70	# GPRMC
+0.026900	-       	-       	0.116800	0.117400	0.117400	0.117400	0.117562	0.117679	      81	# GPGGA
+-       	-       	0.119200	0.172800	0.173400	0.173400	0.173400	0.173540	0.173628	      49	# GPGLL
+-       	0.423900	-       	0.500800	0.501400	0.501400	0.501400	0.501512	0.501644	      70	# GPRMC
+0.032900	-       	-       	0.123700	0.124300	0.124300	0.124300	0.124530	0.124647	      81	# GPGGA
+-       	-       	0.125700	0.179700	0.180200	0.180200	0.180300	0.180398	0.180485	      49	# GPGLL
+-       	0.429900	-       	0.507600	0.508200	0.508200	0.508200	0.508374	0.508507	      70	# GPRMC
+0.026600	-       	-       	0.117600	0.118100	0.118100	0.118100	0.118276	0.118417	      81	# GPGGA
+-       	-       	0.119600	0.173600	0.174100	0.174100	0.174100	0.174257	0.174344	      49	# GPGLL
+-       	0.423800	-       	0.501500	0.502100	0.502100	0.502100	0.502228	0.502359	      70	# GPRMC
+0.026400	-       	-       	0.117400	0.118000	0.118000	0.118000	0.118125	0.118251	      81	# GPGGA
+-       	-       	0.119700	0.173400	0.174000	0.174000	0.174000	0.174105	0.174201	      49	# GPGLL
+-       	0.423600	-       	0.501400	0.501900	0.501900	0.501900	0.502077	0.502218	      70	# GPRMC
+0.026300	-       	-       	0.117300	0.117900	0.117900	0.117900	0.118008	0.118124	      81	# GPGGA
+-       	-       	0.119300	0.173300	0.173800	0.173800	0.173800	0.173963	0.174050	      49	# GPGLL
+-       	0.423500	-       	0.501200	0.501800	0.501800	0.501800	0.501941	0.502074	      70	# GPRMC
+0.027200	-       	-       	0.117200	0.117700	0.117700	0.117700	0.117912	0.118029	      81	# GPGGA
+-       	-       	0.119100	0.173100	0.173700	0.173700	0.173700	0.173828	0.173915	      49	# GPGLL
+-       	0.423300	-       	0.501100	0.501600	0.501600	0.501700	0.501796	0.501928	      70	# GPRMC
+0.030000	-       	-       	0.120000	0.120500	0.120600	0.120600	0.120707	0.120824	      81	# GPGGA
+-       	-       	0.122200	0.176000	0.176600	0.176600	0.176600	0.176706	0.176793	      49	# GPGLL
+-       	0.426900	-       	0.503900	0.504500	0.504500	0.504500	0.504676	0.504808	      70	# GPRMC
+0.027900	-       	-       	0.117800	0.118400	0.118400	0.118400	0.118559	0.118677	      81	# GPGGA
+-       	-       	0.120900	0.173800	0.174400	0.174400	0.174400	0.174535	0.174622	      49	# GPGLL
+-       	0.425100	-       	0.502800	0.503400	0.503400	0.503400	0.503517	0.503649	      70	# GPRMC
+0.026700	-       	-       	0.117700	0.118300	0.118300	0.118300	0.118428	0.118545	      81	# GPGGA
+-       	-       	0.119700	0.173700	0.174200	0.174300	0.174300	0.174401	0.174489	      49	# GPGLL
+-       	0.423900	-       	0.501700	0.502300	0.502300	0.502300	0.502432	0.502564	      70	# GPRMC
+0.027600	-       	-       	0.117600	0.118100	0.118100	0.118100	0.118283	0.118400	      81	# GPGGA
+-       	-       	0.119600	0.173600	0.174100	0.174100	0.174100	0.174258	0.174345	      49	# GPGLL
+-       	0.424500	-       	0.501500	0.502100	0.502100	0.502100	0.502218	0.502349	      70	# GPRMC
+0.027400	-       	-       	0.117500	0.118000	0.118000	0.118000	0.118172	0.118298	      81	# GPGGA
+-       	-       	0.119400	0.173400	0.174000	0.174000	0.174000	0.174106	0.174193	      49	# GPGLL
+-       	0.424400	-       	0.501400	0.501900	0.502000	0.502000	0.502100	0.502241	      70	# GPRMC
+0.028300	-       	-       	0.119300	0.119800	0.119800	0.119900	0.119989	0.120107	      81	# GPGGA
+-       	-       	0.121300	0.175300	0.175800	0.175800	0.175800	0.175965	0.176051	      49	# GPGLL
+-       	0.425500	-       	0.503200	0.503800	0.503800	0.503800	0.503942	0.504073	      70	# GPRMC
+0.030200	-       	-       	0.120100	0.120700	0.120700	0.120700	0.120851	0.120967	      81	# GPGGA
+-       	-       	0.122400	0.176100	0.176700	0.176700	0.176700	0.176830	0.176916	      49	# GPGLL
+-       	0.426300	-       	0.504100	0.504600	0.504700	0.504700	0.504802	0.504934	      70	# GPRMC
+0.027000	-       	-       	0.118000	0.118600	0.118600	0.118600	0.118708	0.118826	      81	# GPGGA
+-       	-       	0.120300	0.174000	0.174500	0.174500	0.174600	0.174688	0.174775	      49	# GPGLL
+-       	0.424200	-       	0.501900	0.502500	0.502500	0.502500	0.502661	0.502793	      70	# GPRMC
+0.026900	-       	-       	0.116800	0.117400	0.117400	0.117400	0.117570	0.117688	      81	# GPGGA
+-       	-       	0.119900	0.172800	0.173400	0.173400	0.173400	0.173543	0.173629	      49	# GPGLL
+-       	0.423800	-       	0.500800	0.501400	0.501400	0.501400	0.501508	0.501639	      70	# GPRMC
+0.026700	-       	-       	0.117700	0.118300	0.118300	0.118300	0.118423	0.118540	      81	# GPGGA
+-       	-       	0.120000	0.173700	0.174200	0.174300	0.174300	0.174404	0.174491	      49	# GPGLL
+-       	0.423900	-       	0.501700	0.502200	0.502200	0.502200	0.502376	0.502508	      70	# GPRMC
+0.026600	-       	-       	0.117600	0.118100	0.118100	0.118100	0.118281	0.118398	      81	# GPGGA
+-       	-       	0.119900	0.173600	0.174100	0.174100	0.174100	0.174252	0.174348	      49	# GPGLL
+-       	0.423600	-       	0.501500	0.502100	0.502100	0.502100	0.502231	0.502372	      70	# GPRMC
diff --git a/www/performance/profile5.txt b/www/performance/profile5.txt
new file mode 100644
index 00000000..bdae796e
--- /dev/null
+++ b/www/performance/profile5.txt
@@ -0,0 +1,103 @@
+# Split latency data, BU-303b, 4800N1, cycle 1s
+#   GPGGA	   GPRMC	   GPGLL	      T1	      D1	       W	      E2	      T2	      D2	  length	tag
+# ---------	---------	---------	---------	---------	---------	---------	---------	---------	---------	--------
+-       	0.372400	-       	0.528400	0.528500	0.528500	0.528500	0.528847	0.529094	      70	# GPRMC
+0.080300	-       	-       	0.260300	0.260400	0.260400	0.260400	0.260755	0.260995	      81	# GPGGA
+-       	0.376300	-       	0.532200	0.532400	0.532400	0.532400	0.532710	0.533043	      70	# GPRMC
+0.076300	-       	-       	0.256200	0.256300	0.256300	0.256400	0.256695	0.256970	      81	# GPGGA
+-       	0.373100	-       	0.529100	0.529200	0.529200	0.529300	0.529555	0.529893	      70	# GPRMC
+0.076000	-       	-       	0.256000	0.256100	0.256100	0.256200	0.256469	0.256766	      81	# GPGGA
+-       	0.764900	-       	0.920900	0.921000	0.921000	0.921100	0.921356	0.921690	      70	# GPRMC
+0.084000	-       	-       	0.263800	0.263900	0.263900	0.264000	0.264292	0.264590	      81	# GPGGA
+-       	0.380800	-       	0.536800	0.536900	0.536900	0.537000	0.537250	0.537585	      70	# GPRMC
+0.075700	-       	-       	0.255700	0.255800	0.255800	0.255900	0.256177	0.256450	      81	# GPGGA
+-       	0.372600	-       	0.528600	0.528800	0.528800	0.528800	0.529096	0.529430	      70	# GPRMC
+0.079600	-       	-       	0.259500	0.259600	0.259600	0.259700	0.260012	0.260289	      81	# GPGGA
+-       	0.376500	-       	0.531500	0.531700	0.531700	0.531700	0.532028	0.532340	      70	# GPRMC
+0.076400	-       	-       	0.256300	0.256500	0.256500	0.256600	0.256878	0.257153	      81	# GPGGA
+-       	0.373300	-       	0.529300	0.529500	0.529500	0.529500	0.529817	0.530128	      70	# GPRMC
+0.085300	-       	-       	0.265200	0.265300	0.265300	0.265400	0.265717	0.265995	      81	# GPGGA
+-       	0.773100	-       	0.929100	0.929200	0.929300	0.929300	0.929591	0.929899	      70	# GPRMC
+0.082100	-       	-       	0.263000	0.263200	0.263200	0.263200	0.263565	0.263838	      81	# GPGGA
+-       	0.380000	-       	0.536000	0.536100	0.536200	0.536200	0.536513	0.536826	      70	# GPRMC
+0.076000	-       	-       	0.255900	0.256000	0.256000	0.256100	0.256409	0.256687	      81	# GPGGA
+-       	0.372900	-       	0.527800	0.528000	0.528000	0.528000	0.528357	0.528669	      70	# GPRMC
+0.078800	-       	-       	0.258700	0.258900	0.258900	0.258900	0.259267	0.259541	      81	# GPGGA
+-       	0.375700	-       	0.529700	0.529800	0.529800	0.529900	0.530199	0.530511	      69	# GPRMC
+0.074600	-       	-       	0.254600	0.254700	0.254700	0.254800	0.255097	0.255372	      81	# GPGGA
+-       	0.371600	-       	0.526500	0.526700	0.526700	0.526700	0.527056	0.527367	      70	# GPRMC
+0.076500	-       	-       	0.256400	0.256600	0.256600	0.256600	0.256966	0.257242	      81	# GPGGA
+-       	0.764400	-       	0.920300	0.920500	0.920500	0.920500	0.920825	0.921132	      70	# GPRMC
+0.092300	-       	-       	0.273300	0.273400	0.273400	0.273500	0.273788	0.274060	      81	# GPGGA
+-       	0.390300	-       	0.545500	0.545700	0.545700	0.545700	0.546197	0.546528	      70	# GPRMC
+0.078200	-       	-       	0.258100	0.258300	0.258300	0.258300	0.258656	0.258930	      81	# GPGGA
+-       	0.375100	-       	0.531100	0.531200	0.531200	0.531300	0.531596	0.531908	      70	# GPRMC
+0.078000	-       	-       	0.258000	0.258100	0.258100	0.258200	0.258493	0.258768	      81	# GPGGA
+-       	0.375000	-       	0.530900	0.531100	0.531100	0.531100	0.531442	0.531755	      70	# GPRMC
+0.075900	-       	-       	0.255800	0.256000	0.256000	0.256000	0.256347	0.256622	      81	# GPGGA
+-       	0.372800	-       	0.528800	0.528900	0.528900	0.529000	0.529284	0.529593	      70	# GPRMC
+0.075700	-       	-       	0.255700	0.255800	0.255800	0.255900	0.256185	0.256461	      81	# GPGGA
+-       	0.764600	-       	0.919600	0.919700	0.919700	0.919800	0.920060	0.920366	      70	# GPRMC
+0.082600	-       	-       	0.263500	0.263700	0.263700	0.263700	0.264040	0.264314	      81	# GPGGA
+-       	0.380500	-       	0.536500	0.536600	0.536600	0.536700	0.536982	0.537296	      70	# GPRMC
+0.076400	-       	-       	0.256400	0.256500	0.256500	0.256600	0.256880	0.257158	      81	# GPGGA
+-       	0.373400	-       	0.524300	0.524500	0.524500	0.524500	0.524825	0.525139	      68	# GPRMC
+0.079300	-       	-       	0.259200	0.259400	0.259400	0.259400	0.259737	0.260012	      81	# GPGGA
+-       	0.376200	-       	0.532200	0.532400	0.532400	0.532500	0.532752	0.533065	      70	# GPRMC
+0.076100	-       	-       	0.256100	0.256200	0.256200	0.256300	0.256580	0.256857	      81	# GPGGA
+-       	0.373100	-       	0.529000	0.529200	0.529200	0.529200	0.529524	0.529837	      70	# GPRMC
+0.080000	-       	-       	0.259900	0.260100	0.260100	0.260100	0.260434	0.260709	      81	# GPGGA
+-       	0.768800	-       	0.924800	0.925000	0.925000	0.925000	0.925306	0.925613	      70	# GPRMC
+0.078800	-       	-       	0.259800	0.259900	0.259900	0.259900	0.260265	0.260537	      81	# GPGGA
+-       	0.376800	-       	0.532700	0.532900	0.532900	0.532900	0.533222	0.533535	      70	# GPRMC
+0.076700	-       	-       	0.256600	0.256800	0.256800	0.256800	0.257138	0.257413	      81	# GPGGA
+-       	0.373600	-       	0.529600	0.529700	0.529700	0.529800	0.530070	0.530383	      70	# GPRMC
+0.079500	-       	-       	0.259400	0.259600	0.259600	0.259700	0.259972	0.260247	      81	# GPGGA
+-       	0.376400	-       	0.532400	0.532500	0.532600	0.532600	0.532909	0.533220	      70	# GPRMC
+0.075400	-       	-       	0.255300	0.255400	0.255500	0.255500	0.255819	0.256094	      81	# GPGGA
+-       	0.372300	-       	0.528300	0.528400	0.528400	0.528500	0.528777	0.529092	      70	# GPRMC
+0.076200	-       	-       	0.256100	0.256300	0.256300	0.256400	0.256672	0.256948	      81	# GPGGA
+-       	0.764100	-       	0.920000	0.920200	0.920200	0.920300	0.920531	0.920837	      70	# GPRMC
+0.079100	-       	-       	0.260000	0.260200	0.260200	0.260200	0.260518	0.260792	      81	# GPGGA
+-       	0.377000	-       	0.532900	0.533100	0.533100	0.533200	0.533459	0.533773	      70	# GPRMC
+0.075900	-       	-       	0.255800	0.256000	0.256000	0.256000	0.256357	0.256634	      81	# GPGGA
+-       	0.372800	-       	0.528900	0.529100	0.529100	0.529100	0.529480	0.529813	      70	# GPRMC
+0.080700	-       	-       	0.260700	0.260900	0.260900	0.260900	0.261210	0.261484	      81	# GPGGA
+-       	0.377700	-       	0.533600	0.533800	0.533800	0.533900	0.534160	0.534470	      70	# GPRMC
+0.076600	-       	-       	0.256500	0.256700	0.256700	0.256700	0.257056	0.257332	      81	# GPGGA
+-       	0.373500	-       	0.529500	0.529600	0.529600	0.529700	0.529982	0.530294	      70	# GPRMC
+0.076400	-       	-       	0.256400	0.256600	0.256600	0.256600	0.256907	0.257182	      81	# GPGGA
+-       	0.765300	-       	0.921300	0.921400	0.921500	0.921500	0.921768	0.922075	      70	# GPRMC
+0.079300	-       	-       	0.260200	0.260400	0.260400	0.260400	0.260738	0.261012	      81	# GPGGA
+-       	0.377200	-       	0.533200	0.533300	0.533300	0.533400	0.533684	0.533997	      70	# GPRMC
+0.080100	-       	-       	0.260100	0.260200	0.260200	0.260300	0.260597	0.260872	      81	# GPGGA
+-       	0.377100	-       	0.533000	0.533200	0.533200	0.533200	0.533522	0.533835	      70	# GPRMC
+0.081000	-       	-       	0.260900	0.261100	0.261100	0.261100	0.261442	0.261717	      81	# GPGGA
+-       	0.377900	-       	0.532900	0.533000	0.533000	0.533100	0.533380	0.533693	      70	# GPRMC
+0.076800	-       	-       	0.256800	0.256900	0.256900	0.257000	0.257298	0.257574	      81	# GPGGA
+-       	0.373800	-       	0.528700	0.528900	0.528900	0.528900	0.529223	0.529533	      70	# GPRMC
+0.075700	-       	-       	0.255600	0.255800	0.255800	0.255800	0.256136	0.256411	      81	# GPGGA
+-       	0.763600	-       	0.919500	0.919700	0.919700	0.919700	0.920004	0.920309	      70	# GPRMC
+0.078500	-       	-       	0.259500	0.259600	0.259600	0.259700	0.259974	0.260246	      81	# GPGGA
+-       	0.376500	-       	0.532400	0.532600	0.532600	0.532600	0.532917	0.533227	      70	# GPRMC
+0.076400	-       	-       	0.256300	0.256500	0.256500	0.256500	0.256839	0.257114	      81	# GPGGA
+-       	0.373300	-       	0.528300	0.528400	0.528400	0.528500	0.528764	0.529076	      70	# GPRMC
+0.075200	-       	-       	0.255200	0.255300	0.255300	0.255400	0.255672	0.255947	      81	# GPGGA
+-       	0.372200	-       	0.528100	0.528200	0.528300	0.528300	0.528589	0.528901	      70	# GPRMC
+0.075100	-       	-       	0.255000	0.255100	0.255100	0.255200	0.255494	0.255770	      81	# GPGGA
+-       	0.372000	-       	0.528000	0.528100	0.528100	0.528200	0.528448	0.528760	      70	# GPRMC
+0.075900	-       	-       	0.256900	0.257000	0.257000	0.257100	0.257357	0.257631	      81	# GPGGA
+-       	0.765000	-       	0.920700	0.920900	0.920900	0.921000	0.921223	0.921532	      70	# GPRMC
+0.087800	-       	-       	0.268700	0.268800	0.268900	0.268900	0.269194	0.269466	      81	# GPGGA
+-       	0.385700	-       	0.540700	0.540800	0.540800	0.540900	0.541143	0.541454	      70	# GPRMC
+0.078600	-       	-       	0.259500	0.259700	0.259700	0.259700	0.260050	0.260324	      81	# GPGGA
+-       	0.375500	-       	0.531500	0.531700	0.531700	0.531700	0.531996	0.532308	      70	# GPRMC
+0.076500	-       	-       	0.256400	0.256500	0.256500	0.256600	0.256888	0.257165	      81	# GPGGA
+-       	0.373400	-       	0.528400	0.528500	0.528500	0.528500	0.528840	0.529151	      70	# GPRMC
+0.076400	-       	-       	0.256200	0.256400	0.256400	0.256400	0.256746	0.257022	      81	# GPGGA
+-       	0.373200	-       	0.529200	0.529300	0.529300	0.529400	0.529681	0.529992	      70	# GPRMC
+0.076100	-       	-       	0.256100	0.256200	0.256200	0.256300	0.256580	0.256855	      81	# GPGGA
+-       	0.765000	-       	0.920000	0.920100	0.920100	0.920200	0.920457	0.920762	      70	# GPRMC
+0.076000	-       	-       	0.256900	0.257100	0.257100	0.257100	0.257438	0.257709	      81	# GPGGA
+-       	0.372900	-       	0.528900	0.529000	0.529000	0.529100	0.529387	0.529699	      70	# GPRMC
+0.075800	-       	-       	0.255800	0.255900	0.255900	0.256000	0.256276	0.256552	      81	# GPGGA