diff options
Diffstat (limited to 'man/ndbmtd.8')
| -rw-r--r-- | man/ndbmtd.8 | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/man/ndbmtd.8 b/man/ndbmtd.8 new file mode 100644 index 00000000000..baadd4eaee2 --- /dev/null +++ b/man/ndbmtd.8 @@ -0,0 +1,388 @@ +'\" t +.\" Title: \fBndbmtd\fR +.\" Author: [FIXME: author] [see http://docbook.sf.net/el/author] +.\" Generator: DocBook XSL Stylesheets v1.75.2 <http://docbook.sf.net/> +.\" Date: 04/06/2010 +.\" Manual: MySQL Database System +.\" Source: MySQL 5.1 +.\" Language: English +.\" +.TH "\FBNDBMTD\FR" "8" "04/06/2010" "MySQL 5\&.1" "MySQL Database System" +.\" ----------------------------------------------------------------- +.\" * set default formatting +.\" ----------------------------------------------------------------- +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.\" ----------------------------------------------------------------- +.\" * MAIN CONTENT STARTS HERE * +.\" ----------------------------------------------------------------- +.\" ndbmtd +.\" MySQL Cluster: ndbmtd +.\" MySQL Cluster: data nodes +.\" data nodes (MySQL Cluster) +.\" storage nodes - see data nodes, ndbd, ndbmtd +.SH "NAME" +ndbmtd \- the MySQL Cluster data node daemon (multi\-threaded version) +.SH "SYNOPSIS" +.HP \w'\fBndbmtd\ \fR\fB\fIoptions\fR\fR\ 'u +\fBndbmtd \fR\fB\fIoptions\fR\fR +.SH "DESCRIPTION" +.PP +\fBndbmtd\fR +is a multi\-threaded version of +\fBndbd\fR, the process that is used to handle all the data in tables using the +NDBCLUSTER +storage engine\&. +\fBndbmtd\fR +is intended for use on host computers having multiple CPU cores\&. Except where otherwise noted, +\fBndbmtd\fR +functions in the same way as +\fBndbd\fR; therefore, in this section, we concentrate on the ways in which +\fBndbmtd\fR +differs from +\fBndbd\fR, and you should consult +\fBndbd\fR(8), for additional information about running MySQL Cluster data nodes that apply to both the single\-threaded and multi\-threaded versions of the data node process\&. +.PP +Command\-line options and configuration parameters used with +\fBndbd\fR +also apply to +\fBndbmtd\fR\&. For more information about these options and parameters, see +\fBndbd\fR(8), and +Section\ \&17.3.2.6, \(lqDefining MySQL Cluster Data Nodes\(rq, respectively\&. +.PP +\fBndbmtd\fR +is also file system\-compatible with +\fBndbd\fR\&. In other words, a data node running +\fBndbd\fR +can be stopped, the binary replaced with +\fBndbmtd\fR, and then restarted without any loss of data\&. (However, when doing this, you must make sure that +MaxNoOfExecutionThreads +is set to an apppriate value before restarting the node if you wish for +\fBndbmtd\fR +to run in multi\-threaded fashion\&.) Similarly, an +\fBndbmtd\fR +binary can be replaced with +\fBndbd\fR +simply by stopping the node and then starting +\fBndbd\fR +in place of the multi\-threaded binary\&. It is not necessary when switching between the two to start the data node binary using +\fB\-\-initial\fR\&. +.PP +Prior to MySQL Cluster NDB 7\&.0\&.6, there were known issues when using +\fBndbmtd\fR +with MySQL Cluster Disk Data tables\&. If you wish to use multi\-threaded data nodes with disk\-based +NDB +tables, you should ensure that you are running MySQL Cluster NDB 7\&.0\&.6 or later\&. (\m[blue]\fBBug#41915\fR\m[]\&\s-2\u[1]\d\s+2, +\m[blue]\fBBug#44915\fR\m[]\&\s-2\u[2]\d\s+2) +.PP +Using +\fBndbmtd\fR +differs from using +\fBndbd\fR +in two key respects: +.sp +.RS 4 +.ie n \{\ +\h'-04' 1.\h'+01'\c +.\} +.el \{\ +.sp -1 +.IP " 1." 4.2 +.\} +You must set an appropriate value for the +MaxNoOfExecutionThreads +configuration parameter in the +config\&.ini +file\&. If you do not do so, +\fBndbmtd\fR +runs in single\-threaded mode \(em that is, it behaves like +\fBndbd\fR\&. +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04' 2.\h'+01'\c +.\} +.el \{\ +.sp -1 +.IP " 2." 4.2 +.\} +Trace files are generated by critical errors in +\fBndbmtd\fR +processes in a somewhat different fashion from how these are generated by +\fBndbd\fR +failures\&. +.RE +.PP +These differences are discussed in more detail in the next few paragraphs\&. +.\" execution threads (MySQL Cluster) +.\" MySQL Cluster: execution threads +.\" ndbmtd: MaxNoOfExecutionThreads +.\" MaxNoOfExecutionThreads: ndbmtd +.\" ndbmtd: trace files +.\" trace files: ndbmtd +.PP +\fBNumber of execution threads\fR. The +MaxNoOfExecutionThreads +configuration parameter is used to determine the number of local query handler (LQH) threads spawned by +\fBndbmtd\fR\&. Although this parameter is set in +[ndbd] +or +[ndbd default] +sections of the +config\&.ini +file, it is exclusive to +\fBndbmtd\fR +and does not apply to +\fBndbd\fR\&. +.PP +This parameter takes an integer value from 2 to 8 inclusive\&. Generally, you should set this parameter equal to the number of CPU cores on the data node host, as shown in the following table: +.TS +allbox tab(:); +lB lB. +T{ +Number of Cores +T}:T{ +Recommended MaxNoOfExecutionThreads Value +T} +.T& +l l +l l +l l. +T{ +2 +T}:T{ +2 +T} +T{ +4 +T}:T{ +4 +T} +T{ +8 or more +T}:T{ +8 +T} +.TE +.sp 1 +.PP +(It is possible to set this parameter to other values within the permitted range, but these are automatically rounded as shown in the +\fBValue Used\fR +column of the next table in this section\&.) +.PP +The multi\-threaded data node process always spawns at least 4 threads: +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +1 local query handler (LQH) thread +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +1 transaction coordinator (TC) thread +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +1 transporter thread +.RE +.sp +.RS 4 +.ie n \{\ +\h'-04'\(bu\h'+03'\c +.\} +.el \{\ +.sp -1 +.IP \(bu 2.3 +.\} +1 subscription manager (SUMA) thread +.RE +.PP +Setting this parameter to a value between 4 and 8 inclusive causes additional LQH threads to be used by +\fBndbmtd\fR +(up to a maximum of 4 LQH threads), as shown in the following table: +.TS +allbox tab(:); +lB lB lB. +T{ +config\&.ini Value +T}:T{ +Value Used +T}:T{ +Number of LQH Threads Used +T} +.T& +l l l +l l l +l l l. +T{ +3 +T}:T{ +2 +T}:T{ +1 +T} +T{ +5 or 6 +T}:T{ +4 +T}:T{ +2 +T} +T{ +7 +T}:T{ +8 +T}:T{ +4 +T} +.TE +.sp 1 +.PP +Setting this parameter outside the permitted range of values causes the management server to abort on startup with the error +Error line \fInumber\fR: Illegal value \fIvalue\fR for parameter MaxNoOfExecutionThreads\&. +.if n \{\ +.sp +.\} +.RS 4 +.it 1 an-trap +.nr an-no-space-flag 1 +.nr an-break-flag 1 +.br +.ps +1 +\fBNote\fR +.ps -1 +.br +.PP +In MySQL Cluster NDB 6\&.4\&.0, it is not possible to set +MaxNoOfExecutionThreads +to 2\&. You can safely use the value 3 instead (it is treated as 2 internally)\&. This issue is resolved in MySQL Cluster NDB 6\&.4\&.1\&. +.sp .5v +.RE +.PP +In MySQL Cluster NDB 6\&.4\&.0 through 6\&.4\&.3, the default value for this parameter was undefined, although the default behavior for +\fBndbmtd\fR +was to use 1 LQH thread, as though +MaxNoOfExecutionThreads +had been set to 2\&. Beginning with MySQL Cluster NDB 7\&.0\&.4, this parameter has an explcit default value of 2, thus guaranteeing this default behavior\&. +.PP +In MySQL Cluster NDB 7\&.0, it is not possible to cause +\fBndbmtd\fR +to use more than 1 TC thread, although we plan to introduce this capability in a future MySQL Cluster release series\&. +.\" MySQL Cluster: log files +.\" log files (MySQL Cluster): ndbmtd +.\" ndbmtd: trace files +.PP +Like +\fBndbd\fR, +\fBndbmtd\fR +generates a set of log files which are placed in the directory specified by +DataDir +in the +config\&.ini +configuration file\&. Except for trace files, these are generated in the same way and have the same names as those generated by +\fBndbd\fR\&. +.PP +In the event of a critical error, +\fBndbmtd\fR +generates trace files describing what happened just prior to the error\' occurrence\&. These files, which can be found in the data node\'s +DataDir, are useful for analysis of problems by the MySQL Cluster Development and Support teams\&. One trace file is generated for each +\fBndbmtd\fR +thread\&. The names of these files follow the pattern +ndb_\fInode_id\fR_trace\&.log\&.\fItrace_id\fR_t\fIthread_id\fR, where +\fInode_id\fR +is the data node\'s unique node ID in the cluster, +\fItrace_id\fR +is a trace sequence number, and +\fIthread_id\fR +is the thread ID\&. For example, in the event of the failure of an +\fBndbmtd\fR +process running as a MySQL Cluster data node having the node ID 3 and with +MaxNoOfExecutionThreads +equal to 4, four trace files are generated in the data node\'s data directory; if the is the first time this node has failed, then these files are named +ndb_3_trace\&.log\&.1_t1, +ndb_3_trace\&.log\&.1_t2, +ndb_3_trace\&.log\&.1_t3, and +ndb_3_trace\&.log\&.1_t4\&. Internally, these trace files follow the same format as +\fBndbd\fR +trace files\&. +.PP +The +\fBndbd\fR +exit codes and messages that are generated when a data node process shuts down prematurely are also used by +\fBndbmtd\fR\&. See +\m[blue]\fBndbd Error Messages\fR\m[]\&\s-2\u[3]\d\s+2, for a listing of these\&. +.if n \{\ +.sp +.\} +.RS 4 +.it 1 an-trap +.nr an-no-space-flag 1 +.nr an-break-flag 1 +.br +.ps +1 +\fBNote\fR +.ps -1 +.br +.PP +It is possible to use +\fBndbd\fR +and +\fBndbmtd\fR +concurrently on different data nodes in the same MySQL Cluster\&. However, such configurations have not been tested extensively; thus, we cannot not recommend doing so in a production setting at this time\&. +.sp .5v +.RE +.SH "COPYRIGHT" +.br +.PP +Copyright 2007-2008 MySQL AB, 2008-2010 Sun Microsystems, Inc. +.PP +This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. +.PP +This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. +.PP +You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/. +.sp +.SH "NOTES" +.IP " 1." 4 +Bug#41915 +.RS 4 +\%http://bugs.mysql.com/bug.php?id=41915 +.RE +.IP " 2." 4 +Bug#44915 +.RS 4 +\%http://bugs.mysql.com/bug.php?id=44915 +.RE +.IP " 3." 4 +ndbd Error Messages +.RS 4 +\%http://dev.mysql.com/doc/ndbapi/en/ndbd-error-messages.html +.RE +.SH "SEE ALSO" +For more information, please refer to the MySQL Reference Manual, +which may already be installed locally and which is also available +online at http://dev.mysql.com/doc/. +.SH AUTHOR +Sun Microsystems, Inc. (http://www.mysql.com/). |