From 6b8e90545e918a4653281b3672a873e948f12b65 Mon Sep 17 00:00:00 2001 From: Gustavo Noronha Silva Date: Mon, 2 May 2022 14:02:23 -0300 Subject: Apply known iocost solutions to block devices Meta's resource control demo project[0] includes a benchmark tool that can be used to calculate the best iocost solutions for a given SSD. [0]: https://github.com/facebookexperimental/resctl-demo A project[1] has now been started to create a publicly available database of results that can be used to apply them automatically. [1]: https://github.com/iocost-benchmark/iocost-benchmarks This change adds a new tool that gets triggered by a udev rule for any block device and queries the hwdb for known solutions. The format for the hwdb file that is currently generated by the github action looks like this: # This file was auto-generated on Tue, 23 Aug 2022 13:03:57 +0000. # From the following commit: # https://github.com/iocost-benchmark/iocost-benchmarks/commit/ca82acfe93c40f21d3b513c055779f43f1126f88 # # Match key format: # block::name:: # 12 points, MOF=[1.346,1.346], aMOF=[1.249,1.249] block:*:name:HFS256GD9TNG-62A0A:fwver:*: IOCOST_SOLUTIONS=isolation isolated-bandwidth bandwidth naive IOCOST_MODEL_ISOLATION=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119 IOCOST_QOS_ISOLATION=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00 IOCOST_MODEL_ISOLATED_BANDWIDTH=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119 IOCOST_QOS_ISOLATED_BANDWIDTH=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00 IOCOST_MODEL_BANDWIDTH=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119 IOCOST_QOS_BANDWIDTH=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00 IOCOST_MODEL_NAIVE=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119 IOCOST_QOS_NAIVE=rpct=99.00 rlat=8807 wpct=99.00 wlat=59023 min=75.00 max=100.00 The IOCOST_SOLUTIONS key lists the solutions available for that device in the preferred order for higher isolation, which is a reasonable default for most client systems. This can be overriden to choose better defaults for custom use cases, like the various data center workloads. The tool can also be used to query the known solutions for a specific device or to apply a non-default solution (say, isolation or bandwidth). Co-authored-by: Santosh Mahto --- man/iocost.conf.xml | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++ man/rules/meson.build | 1 + 2 files changed, 77 insertions(+) create mode 100644 man/iocost.conf.xml (limited to 'man') diff --git a/man/iocost.conf.xml b/man/iocost.conf.xml new file mode 100644 index 0000000000..be74244267 --- /dev/null +++ b/man/iocost.conf.xml @@ -0,0 +1,76 @@ + + + + + + + iocost.conf + systemd + + + + iocost.conf + 5 + + + + iocost.conf + Configuration files for the iocost solution manager + + + + + /etc/systemd/iocost.conf + /etc/systemd/iocost.conf.d/*.conf + + + + + Description + + This file configures the behavior of iocost, a tool mostly used by + systemd-udevd8 rules + to automatically apply I/O cost solutions to /sys/fs/cgroup/io.cost.*. + + The qos and model values are calculated based on benchmarks collected on the + iocost-benchmark + project and turned into a set of solutions that go from most to least isolated. + Isolation allows the system to remain responsive in face of high I/O load. + Which solutions are available for a device can be queried from the udev metadata attached to it. By + default the naive solution is used, which provides the most bandwidth. + + + + + + Options + + All options are configured in the [IOCost] section: + + + + + TargetSolution= + + Chooses which I/O cost solution (identified by named string) should be used + for the devices in this system. The known solutions can be queried from the udev metadata + attached to the devices. If a device does not have the specified solution, the first one + listed in IOCOST_SOLUTIONS is used instead. + + E.g. TargetSolution=isolated-bandwidth. + + + + + + See Also + + udevadm8, + The iocost-benchmarks github project, + The resctl-bench + documentation details how the values are obtained + + + + diff --git a/man/rules/meson.build b/man/rules/meson.build index cdf98eaaf0..ca3b471281 100644 --- a/man/rules/meson.build +++ b/man/rules/meson.build @@ -24,6 +24,7 @@ manpages = [ ['hostnamectl', '1', [], 'ENABLE_HOSTNAMED'], ['hwdb', '7', [], 'ENABLE_HWDB'], ['integritytab', '5', [], 'HAVE_LIBCRYPTSETUP'], + ['iocost.conf', '5', [], ''], ['journal-remote.conf', '5', ['journal-remote.conf.d'], 'HAVE_MICROHTTPD'], ['journal-upload.conf', '5', ['journal-upload.conf.d'], 'HAVE_MICROHTTPD'], ['journalctl', '1', [], ''], -- cgit v1.2.1