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This page has news, information, documentation and links software for the sysstat utilities that I created for Linux. The sysstat utilities are a collection of performance monitoring tools for Linux. These include sar, sadf, mpstat, iostat, tapestat, pidstat, cifsiostat  and sa tools. Go to the Features page to display a list of sysstat's features, or see the Documentation page to learn some more about them.
Sysstat is Open Source / Free Software, and is freely available under the GNU General Public License, version 2.


Sunday June 4th, 2023

My internet provider has decided to stop hosting personal web sites at the end of year 2023.
As a consequence this page will no longer be updated.
Go now to GitHub to keep up-to-date with sysstat development.

Sunday January 29th, 2023

Sysstat 12.7.2 released (development version).
Sysstat 12.6.2 released (stable version).
This version adds a new activity to sar and sadf: Batteries capacity statistics, which can be displayed using option "-m BAT".
Output has also been improved so that healthy metrics values (for all sysstat commands) are no longer be displayed in "red" (or any other specific color).
Last, starting and ending times can now be entered as a number of seconds since the Epoch with sar and sadf's options -s/-e.

Sunday November 6th, 2022

Sysstat 12.7.1 released (development version).
Sysstat 12.6.1 released (stable version).
This version adds some small new features, like option -H to mpstat to handle vCPU physical hotplug, or true time mode support to sadf's SVG output.
It also fixes several bugs, one of which has been the object of a security advisory (CVE-2022-39377).

Monday February 28th, 2022

Sysstat 12.6.0 released (stable version).
This version adds a new metric (softnet backlog) to the software-based network processing activity. It also fixes several bugs concerning the recent interrupts statistics rewritten code, and to metrics names used by sadf in the PCP output format..

Monday February 28th, 2022

Sysstat 12.6.0 released (stable version).
This version adds a new metric (softnet backlog) to the software-based network processing activity. It also fixes several bugs concerning the recent interrupts statistics rewritten code, and to metrics names used by sadf in the PCP output format..

Monday February 28th, 2022

Sysstat 12.5.6 released (development version).
Sysstat 12.4.5 released (stable version).
Please first spare a thought for the Ukrainian people suffering this brutal assault from a bloodthirsty megalomaniac. Nothing personal against my Russian friends here since I have always made a distinction between peoples and their leaders. Yet today everybody should stand with Ukraine.
This version includes a complete rewriting of the code used to collect and display interrupts statistics. These statistics are now collected from the /proc/interrupts file instead of the /proc/stat one, and are displayed for each CPU.
It also includes a few bugfixes concerning sar and sadf's PCP output format.
This version is the last one from current development series. Next version will be 12.6.0, starting a new stable branch.

Sunday December 5th, 2021

Sysstat 12.5.5 released (development version).
Sysstat 12.4.4 released (stable version).
This is mainly a bugfix version (iostat, mpstat). See the Changelog page for more details.

Monday June 7th, 2021

Sysstat 12.5.4 released (development version).
This version brings better integration with PCP (thanks go to Nathan Scott). It also adds a small improvement to the pidstat command: Using option -e and not specifying any interval or count values on the command line will make pidstat show global task statistics when the task terminates.

Sunday February 14th, 2021

Sysstat 12.5.3 released (development version).
Sysstat 12.4.3 released (stable version).
This also is mainly a bugfix version (sar, sadf). One noteworthy new feature is the addition of Link Time Optimization (LTO) support for smaller binary executables (use --enable-lto to enable it when compiling sysstat).

Saturday December 19th, 2020

Sysstat 12.5.2 released (development version).
Sysstat 12.4.2 released (stable version).
I felt compelled to release this new version because of an annoying bug concerning structures alignment on 32 bit systems. It made saDD datafiles created on 32 bit systems unreadable on 64 bit ones. And bugs impacting datafiles structure and/or format are always pernicious... So please upgrade. Thanks go to Aleksei Nikiforov for reporting (and fixing) it..

Saturday November 21st, 2020

Sysstat 12.5.1 released (development version).
Sysstat 12.4.1 released (stable version).
Again, this is mainly a bugfix release with some small improvements lying around... Nothing to write home about, but I thought it was time to make a release, the previous one being almost 4 months old.

Friday July 31st, 2020

Sysstat 12.4.0 released (stable version).
Sysstat 12.2.3 released (stable version).
No breaking new features in sysstat release 12.4.0 but numerous small improvements over the last previous version. Among them:
  • All the sysstat commands now display their statistics in color by default when the output is connected to a terminal,
  • sar "pretty-prints" the device names by default, which means you won't need to use option -p with option -d to display the device names as they appear in /dev,
  • You can tell the sa2 script to wait for a random delay before executing in order to prevent a massive I/O burst on some systems,
  • You can also tell the sa1 script to insert a comment in current daily datafile saDD on system suspend and resume,
... and more ! See the changelog available from the Download page above for the full details.

Friday May 8th, 2020

Sysstat 12.3.3 released (development version).
Sysstat 12.2.2 released (stable version).

Exciting new features in this version include:
  • sar/sadc collect and display Pressure-Stall Information statistics. These metrics have been added during the 4.20 development cycle of the Linux kernel. They can be displayed with "sar -q {CPU | LOAD | MEM}",
  • iostat has gained support devices managed by drivers in userspace like spdk. New flags (-f / +f) have been added so that the user can specify an alternate location for statistics files.
This version also includes various bug fixes. Enjoy!

Friday April 10th, 2020

Sysstat 12.3.2 released (development version).
pidstat and cifsiostat commands have been largely rewritten in this version. They now use a linked list and dynamic allocation for all the items being monitored. Memory footprint should be much smaller (especially for pidstat). Several bugs have also been fixed in pidstat.

Friday December 27th, 2019

Sysstat 12.3.1 released (development version).
Sysstat 12.2.1 released (stable version).

This version includes new interesting features such as:
  • The possibility to display system topology (logical core, socket and NUMA node numbers) with mpstat,
  • Statistics for flush I/O operations with iostat,
  • Support for SMB2 version of statistics file for the cifsiostat command.
It also fixes some bugs concerning iostat and sadf. Enjoy!

Monday September 30th, 2019

Sysstat 12.1.7 released (development version).
The main new feature brought by this version is the support for stable identifiers for sar disks statistics. This stable identifier (which won't change across reboots) is the WWN (World-Wide Name) of the device.
The sar and sadf commands included in this version are also ready to read new formats of binary data files which could arrive in a (hopefully) distant future.

Monday November 11th, 2019

Sysstat 12.2.0 released (stable version).
Nothing to get really excited about this version which merely includes a few bugfixes and adds small improvements to sar and sadf. But this version marks the beginning of a new stable series, which is why you should upgrade anyway :-)

Monday September 30th, 2019

Sysstat 12.1.7 released (development version).
The main new feature brought by this version is the support for stable identifiers for sar disks statistics. This stable identifier (which won't change across reboots) is the WWN (World-Wide Name) of the device.
The sar and sadf commands included in this version are also ready to read new formats of binary data files which could arrive in a (hopefully) distant future.

Wednesday August 14th, 2019

Sysstat 12.1.6 released (development version).
Sysstat 12.0.6 released (stable version).

In this development version, the iostat command has been heavily modified for better performance. In particular devices structures are now dynamically allocated to make sure you won't miss a device if many of them are added to the system while iostat is running. Also sysstat test environment now includes a large set of non regression tests for iostat.

Friday May 31st, 2019

Sysstat 12.1.5 released (development version).
Sysstat 12.0.5 released (stable version).

This version completes the support for PCP output format with sadf: All statistics collected by sar/sadc can now be exported to a PCP archive file.
This version also includes now a simulation test environment. This makes it possible to run non regression tests with reproducible results because tests are run in a simulated environment composed of kernel files with predefined values.
For now, only non regression tests have been added for sar, sadc and sadf commands. Yet they have permitted to identify several bugs which have been fixed here and also backported to version 12.0.5.

Thursday April 18th, 2019

Sysstat 12.1.4 released (development version).
Sysstat 12.0.4 released (stable version).

This version adds initial support for PCP (Performance Co-Pilot) output format for better integration. sadf can now export part of its data to a PCP archive file. This support is still experimental and will be completed in next sysstat version.
This version also fixes several bugs. The major ones are:
  • autofs entries in /etc/mtab are now ignored so that sar/sadf don't mount the corresponding filesystems when reading their statistics.
  • JSON output for iostat and mpstat has been improved so that the commands can be interrupted with ^C (SIGINT signal) and we still get a valid JSON output.

March 2019

Happy birthday sysstat ! :-)

This year marks the 20th anniversary of the birth of sysstat! I released the first version on March 3rd, 1999 after I discovered the sar and iostat commands on an AIX system I was playing with. Unfortunately these commands were non-existent on Linux at that time, so I decided to write them starting from scratch.

Since then sysstat has greatly improved, gaining many new features and has seen the introduction of new commands (sadf, pidstat…) to become a key player in diagnosing performance issues widely used on most Linux environments today. Here are a few numbers to illustrate the activity around sysstat: More than 34,000 lines of code, around 180 versions released over the past 20 years, dozens of contributors from all over the world, and a total estimated cost to develop of $ 1,097,534 (estimated with sloccount on current upstream development branch).

Though a wife, two young children and a demanding job (in no way related to Linux! :-) ) now keep me busy for most of my time, I still certainly enjoy working on sysstat and hope things will go on for a long time.

Thank you for your support.

Sebastien Godard (sysstat <at> orange <dot> fr)

Friday February 15th, 2019

Sysstat 12.1.3 released (development version).
With this version, the user will be able to select different color palettes to draw the SVG graphs with sadf. One of those palettes can be fully customized using an environment variable (S_COLORS_PALETTE). See conversation on GitHub here.
This version also adds a new flag (-f) to sadc to force fdatasync() use when data are written (this feature has been contributed by Kyle Walker).

Friday December 14th, 2018

Sysstat 12.1.2 released (development version).
Sysstat 12.0.3 released (stable version).

This development version adds support for discard I/O statistics to iostat and sar commands. Statistics for discard operations have been recently added to Linux kernel version 4.19. Previous kernels didn't separate discard I/Os from writes in the block layer statistics. iostat's reports are also modified so that the user can better choose how things are displayed, using switches like "-s" to get a narrow output fitting on a 80-characters wide screen, or "-h" to get a human-friendly output.
Last, this version fixes several important bugs. Please upgrade!

Saturday October 13th, 2018

Sysstat 12.1.1 released (development version).
Sysstat 12.0.2 released (stable version).

Sysstat 11.6.6 released (stable version) (EOL).
Sysstat 11.4.11 released (stable version) (EOL).

This version mainly includes bugfixes. The only noteworthy new feature is the addition of two new metrics to sar -H (Hugepage activity): HugePages_Rsvd and HugePages_Surp. Also sadf has been made more robust to corrupted datafiles, enabling it to complete its job even if an unexpected end of datafile is met.

Monday August 6th, 2018

Sysstat 12.0.1 released (stable version).
Version 12.0.1 fixes a silly, nasty bug found in previous version (12.0.0) which could make your sar daily datafiles (files named saDD and saved in the /var/log/sa directory) unreadable by future sar versions. This would be a pity :-) So please upgrade!

Friday August 3rd, 2018

Sysstat 12.0.0 released (stable version).
Sysstat 11.6.5 released (stable version).

Version 12.0.0 mainly focuses on SVG output from the sadf command, with a lot of bugfixes and the addition of a new option ("showtoc") that will enable the user to quickly navigate through graphs.
Version 12.0.0 is also the first stable version that includes the new, compact and flexible binary format for sar.

Friday June 1st, 2018

Sysstat 11.7.4 released (development version).
Sysstat 11.6.4 released (stable version).

Sysstat 11.4.10 released (stable version).

This version adds several new options to control:
  • The number of decimal places used by sysstat commands (sar, cifsiostat, iostat, mpstat and pidstat),
  • The network interfaces, block devices and filesystems for which statistics shall be displayed by sar or sadf.
Note that this version also redefines the metric kbmemused (amount of used memory displayed by sar) to be consistent with the output of commands such as top(1) and free(1). See sar's manual page.

Friday April 6th, 2018

Sysstat 11.7.3 released (development version).
Sysstat 11.6.3 released (stable version).

Sysstat 11.4.9 released (stable version).

This version has improved support for offline/online CPU (sar/sadf and mpstat). It also adds a new option to sar (option "-z") to omit output for any devices for which there was no activity during the sample period (this option already existed for iostat). Last it contains several important bug fixes, among them:
  • A possible crash related to the new binary format used by sar, which could happen when buffers needed to be reallocated to accomodate more devices added to the system,
  • The %CPU value displayed by pidstat for processes using more than 100% of a core.

Monday February 12th, 2018

Sysstat 11.7.2 released (development version).
After one additional month of hard work, sysstat version 11.7.2 seems to be quite stable on my machine. It should now be possible to use it safely on production systems. BTW I told you that sar's data files new binary format would be at least 25% smaller than with previous versions. I could have even said 30% to 45% smaller!
Version 11.7.2 also includes a rewritten function that will enable you to convert your old data files (from versions 9.1.6 and later) to the up-to-date format (11.7.2).
Please upload, test and tell me if anything goes wrong.

Friday January 12th, 2018

Sysstat 11.7.1 released (development version).
Sysstat 11.6.2 released (stable version).

Sysstat 11.4.8 released (stable version).

Sysstat 11.2.14 released (stable version) [EOL].

Version 11.7.1 includes major changes concerning sar’s binary data file format and how sar works. Among them:
  • A binary data file should take much less space on disk thanks to new optimizations on how values are stowed in memory. The space saved is estimated at least at 25% compared to previous format.
  • Structures are no longer statically allocated, meaning that the system can now register as many new devices (disks, network interfaces, etc.) as needed and you will find all of them saved in your saXX data file (provided that you have selected the corresponding activities to collect). Previous version could lead to some devices being ignored and going unnoticed if no free structures were left.
  • Sar (and sadf) will now be able to read a binary data file whatever its endianness is: Both big-endian and little-endian files can be read by the same sar or sadf executable.
  • More flexibility has been added to sar’s binary data file format. I cannot promise that the format won’t change again in the future but it should now be possible to add new metrics or activities without making the format unreadable by older sar versions (starting with version 11.7.1). Older versions will be able to read newer formats but will display only the metrics they currently know.
Version 11.7.1 is a development version. As such, it is still NOT ready for use in production. Yet I would really like to have it tested by the maximum number of users and get feedback! :-)

NOTE: The function provided by sadf (option –c) to convert an old data file to the up-to-date format has been temporarily inhibited. This function will be working again in next sysstat version (11.7.2).

Wednesday November 1st, 2017

Sysstat 11.6.1 released (stable version).
Sysstat 11.4.7 released (stable version).
Sysstat 11.2.13 released (stable version).

These versions fix the bugs found these past two months. I release them now since the next major sysstat version (11.7.1) is still under development and it could take some time for me to complete. It will include deep changes to sar's data files format.

Monday August 14th, 2017

Sysstat 11.6.0 released (stable version).
Sysstat 11.4.6 released (stable version).
Sysstat 11.2.12 released (stable version).

Version 11.6.0 (the first of a new stable series) mainly focuses on the pidstat command, with the addition of two new options: Option -e can be used to pass a program to execute and make pidstat monitor it, whereas option -H tells pidstat to display timestamps in seconds since the Epoch.
Also these versions revert a fix (added in previous sysstat version to fix a possible sadc crash on ARM architecture) that could cause segmentation faults in some cases.

Wednesday July 5th, 2017

Sysstat 11.5.7 released (development version).
Sysstat 11.4.5 released (stable version).

Sysstat 11.2.11 released (stable version).

Improvements added here mainly concern the iostat command: New metrics added to the extended statistics report, a new switch (-s) to display a short (narrow) version of the report that will fit in 80 characters wide screens, the JSON output that now depends on options used... Also to be noted: Several metrics (from iostat and sar) are now expressed in kilobytes instead of sectors.
Last but not least, this development version includes a set of bugfixes that you will also find in the 11.4.x and 11.2.x series.

Wednesday May 10th, 2017

Sysstat 11.5.6 released (development version).
Sysstat 11.4.4 released (stable version).

Sysstat 11.2.10 released (stable version).

The main new feature added to sysstat version 11.5.6 concerns the mpstat command: It can now display statistics based on NUMA nodes placement (see its new switch "-n").
Other changes included here are bugfixes that have also been backported to the 11.4.x and 11.2.x series.

Monday February 27th, 2017

Sysstat 11.5.5 released (development version).
This version includes some minor new features, notably for the creation of SVG graphs with sadf: The user can now put several charts on the same row (option "packed" to be used with "sadf -O") and he can also explicitly specify the canvas height (option "height=...").
Besides, a new metric (%wait field) has been added to the CPU utilization report displayed by pidstat. This field shows the percentage of CPU spent by the task while waiting to run.

Wednesday January 11th, 2017

Sysstat 11.5.4 released (development version).
Sysstat 11.4.3 released (stable version).

Sysstat 11.2.9 released (stable version).

I have added a new output format to sadf (the "raw" output format) that I personally needed for debugging purposes. With this format, counters values are printed as read from the kernel.
This version also removes memory statistics displayed by "sar -R" to keep only those displayed by "sar -r" (the latter are those that are really meaningful).
Last the development and stable versions include a patch to better handle dynamically registered devices (disks, network interfaces...)

Tuesday December 06th, 2016

Sysstat 11.5.3 released (development version).
Several new features have been added into this development version. First a new metric, providing available free memory, has been added to sar (it can be displayed with option -r). Also a new option ("showidle") can be used with sadf's option -O to display CPU %idle state in SVG graphs created by sadf. Last a new option ("--human") has been added to most sysstat commands (sar, iostat, pidstat, etc.) to display sizes in a human readable format: See the screenshot below...

Human readable output

Friday November 04th, 2016

Sysstat 11.5.2 released (development version).
Sysstat 11.4.2 released (stable version).

Sysstat 11.2.8 released (stable version).

In this developement version, sar now reports statistics for software-based network processing, based on data collected from the /proc/net/softnet_stat file. This will be particularly useful for the sysadmin as this file's contents is not easy to read (values are printed in hex) and proper documentation was lacking. Development and stable versions also include their bunch of bug fixes. See the changelog available from the download page.

Friday September 23rd, 2016

Sysstat 11.5.1 released (development version).
Sysstat 11.4.1 released (stable version).

Sysstat 11.2.7 released (stable version).

This development version adds JSON output to mpstat and iostat commands. The development and stable versions also fix two outstanding bugs: one concerning sadf ability to convert an old datafile to up-to-date format,and the other concerning pidstat which omitted kernel threads when using -l option. Please upgrade.

Monday August 15th, 2016

Sysstat 11.4.0 released (stable version).
Sysstat 11.2.6 released (stable version).

Only small bug fixes have been added into these versions. Sysstat 11.4.0 is the first stable version including SVG support for sar/sadf. Sysstat 11.2.6, from the previous stable series, doesn't include SVG support. Enjoy!

Friday June 24th, 2016

Sysstat 11.3.5 released (development version).
Sysstat 11.2.5 released (stable version).
This version concludes the addition of the new SVG (Scalable Vector Graphics) output format to sadf. It is now possible to draw graphs for almost every sar's activity. This version also adds a new option (named "oneday"), to be used with sadf's switch -O, to display graphs data over a period of 24 hours. Last, this version includes the usual set of bug fixes (also backported to the stable 11.2.x branch).

Saturday May 14th, 2016

Sysstat 11.3.4 released (development version).
Sysstat 11.2.4 released (stable version).
sadf can output an SVG graph for many more activities here (fan speed and temperature sensors, I/O and transfer rate statistics, network activities, etc.) Interestingly enough, this version also adds a new switch to sadf (-O) to pass extra options enabling the user to control SVG output. Two such options are currently supported: "autoscale" and "skipempty" (see sadf(1) manual page).

Saturday April 9th, 2016

Sysstat 11.3.3 released (development version).
Sysstat 11.2.3 released (stable version).
This version carries on improving SVG support by sadf: You can now draw graphs for CPU statistics (see a sample output below), CPU frequency statistics, memory and swap statistics, and queue length and load average statistics.

Graph for CPU statistics

Sunday March 13th, 2016

Sysstat 11.3.2 released (development version).
Sysstat 11.2.2 released (stable version).
This version improves SVG support by sadf, with 3 more activities for which graphs can now be drawn: Paging activity, network interfaces statistics and swapping statistics. SVG output has been updated to make it fully compliant with SVG 1.1 standard. Last, several longstanding bugs have been fixed here and also included in the stable 11.2.2 version.

Sunday February 21st, 2016

Sysstat 11.3.1 released (development version).
Sysstat released (stable version).
The sar and sadf tools in this development version have been largely reworked to prepare the addition of a new output format to sadf: SVG (Scalable Vector Graphics). At the present time, graphs can be generated only for task creation and switching activity as a "proof of concept" (this corresponds to the output of sar -w). Here is a sample graph that you can get with "sadf -g /var/log/sa/saDD -- -w > graph.svg". Other sar activities will be added in the next sysstat versions to come. Ultimately you will be able to draw graphs using sysstat's standard tools (sar and sadf)! Life is cool...! :-)

Sunday December 27th, 2015

Sysstat 11.2.0 released (stable version).
This version is the first one of a new stable series, including all the new features from the previous 11.1.x development series. Various bugs have been fixed and small improvements added since the last 11.1.8 version. Best wishes for the festive season! :-)

Friday October 23rd, 2015

Sysstat 11.1.8 released (development version).
Sysstat 11.0.8 released (stable version).
This development version adds color support for pidstat, tapestat and cifsiostat commands. All sysstat commands now support smart output colorization for easier statistics reading. It's also possible to customize the colors with the S_COLORS_SGR environment variable. Read the manual pages to know how to use it. Enjoy!

Sunday September 20th, 2015

Sysstat 11.1.7 released (development version).
Sysstat 11.0.7 released (stable version).
The iostat, mpstat and sar commands can now display their statistics in color on the terminal. It's a nice feature I've had in mind for a long time. Colors are selected depending on the values to display (eg. zero or non zero value; low / medium / high percentage value...). To enable this feature, just set the S_COLORS environment variable. Here is a sample output from the mpstat command:

I plan to allow the user to cutomize the colors in a future sysstat release.
This version also includes important fixes for the new tapestat command and also for pidstat.

Monday August 24th, 2015

Sysstat 11.1.6 released (development version).
Sysstat 11.0.6 released (stable version).
This development version includes a new command: tapestat. tapestat is aimed at displaying statistics for tape drives connected to the system. It requires the newest kernel version 4.2 (which has still not been released as of this writing) to work. This new command has been contributed by Shane Seymour from HP.

Friday June 12th, 2015

Sysstat 11.1.5 released (development version).
Sysstat 11.0.5 released (stable version).
This version adds support for Fibre Channel HBA statistics (contributed by Steve Kay). It also includes its bunch of fixes based on static analysis reported by Coverity.

Tuesday April 7th, 2015

Sysstat 11.1.4 released (development version).
Sysstat 11.0.4 released (stable version).
Lots of bug fixes and improvements here. Peter Schiffer, Steve Kay and Dimitrios Apostolou are the main contributors for this release. Among the new features, you will now be able to display the mountpoint name instead of the filesystem name when displaying filesystem statistics with sar. And this version also includes sargraph2 in the contrib directory, a promising new plotting tool working with sar and contributed by Dimitrios.

Friday February 13th, 2015

Sysstat 11.1.3 released (development version).
Sysstat 11.0.3 released (stable version).
Five new metrics have been added to memory statistics displayed by sar. You now have to enter "sar -r ALL" to display all the memory metrics as there are many of them now (entering only "sar -r" displays the usual memory metrics).
Sysstat 11.1.3 has also undergone a complete Coverity static analysis (thanks go to Peter Schiffer from RedHat), resulting in many small fixes being included here.
Last some work has been done with the configure script to make it easier for distro maintainers to package sysstat. Enjoy!

Sunday October 19th, 2014

Sysstat 11.1.2 released (development version).
Sysstat 11.0.2 released (stable version).
Version 11.1.2 includes two new commands in the contrib directory: irqtop (contributed by Robert Elliott from HP), which monitors differences in /proc/interrupts and /proc/softirqs per CPU along with CPU statistics, and irqstat (contributed by Lance Shelton from SanDisk/Fusion-io) designed for NUMA systems with many processors. These two commands should be merged in a future sysstat version.
Apart from that, this version includes mainly bug fixes (which you can find in the stable 11.0.2 version).

Saturday August 30th, 2014

Sysstat 11.1.1 released (development version).
Sysstat 11.0.1 released (stable version).
From now on I will maintain two branches concurrently: one for the stable versions of sysstat including only bug fixes, and one for the development versions including all the newest features (and also the bug fixes added to the stable branch). A development version and a stable version will always be released at the same time.
Wrt sysstat 11.1.1, the main new feature here is the addition of a new switch to sadf (-c) that enables the user to convert a binary datafile with an old format (at least 9.1.6) to the up-to-date format (which is 11.1.1 as of today).

Tuesday June 17th, 2014

Sysstat 11.0.0 released (stable version).
Sysstat is back with a stable version. This one includes interesting new features. First the pidstat command has been enhanced with the addition of two new options: -R (to display task scheduling priority and policy information) and -G (to filter processes by name, displaying all threads of matching processes). Then new enhancements have been brought to sar, sadc and sadf with regards to standard system activity daily data files: These may now be named "saYYYYMMDD" instead of "saDD" using sar's and sadc's option -D, and they can be located in a directory which can be different from the standard /var/log/sa place. The new directory can be set in an environment variable (SA_DIR, used by sa1/sa2 scripts) or directly given on the command line to sar/sadc/sadf.

Tuesday March 18th, 2014

Sysstat 10.3.1 released (development version).
I had to switch back to a development version because of a change of sar's datafiles format. But this is (really) for a good cause... After a period of hard work, this version of sysstat includes a long awaited feature: sar can now take into account a change of CPU count in its datafiles. On virtual machine, after CPU change (e.g. power off  machine -> add 1 CPU -> power on machine), you will no longer lose data (from today) from the current saXX file. The restart mark (this is the LINUX RESTART message inserted when sadc is called without any parameters) will be used by sar to know that CPU count has changed.
Note that I plan to go back to a stable series for next sysstat version (which will be 11.0.0).

Sunday January 19th, 2014

Sysstat 10.2.1 released (stable version).
In this version, pidstat I/O statistics includes a new metric giving per-task block I/O delays. There are also some other small improvements: The addition of a new option to configure script (--enable-copy-only) or the data file creation date being now displayed by sadf.

Sunday November 3rd, 2013

Sysstat 10.2.0 released (stable version).
This is yet another stable series! This version mainly focuses on pidstat, with several bug fixes and the addition of a new option (-v) enabling the user to display the number of threads and file descriptors associated with tasks.

Friday September 13th, 2013

Sysstat 10.1.7 released (development version).
Various fixes all around here. And worth noting is the addition of a new metric to sar network devices statistics: %ifutil, giving the utilization percentage of the network interface cards. Download and enjoy!

Sunday June 9th, 2013

Sysstat 10.1.6 released (development version).
The main new feature added here is the ability for sar to display filesystems statistics (blocks and inodes utilization) with its new option "-F". Also several (small) bugs have been fixed.

Thursday April 25th, 2013

Good news! Sysstat is now on GitHub and I have set up a public repository available for all of you willing to contribute!

Sunday March 31st, 2013

Sysstat 10.1.5 released (development version).
This version fixes some more bugs. We found that systemd unit file could no longer be installed because a macro wasn't expanded in configure script. This is fixed here. Also mpstat has been updated so that the number of interrupts per processor actually add up to the number displayed for CPU "all".

Friday March 8th, 2013

Sysstat 10.1.4 released (development version).
There are two main improvements in this version: The first one concern commands like sar, pidstat and mpstat which now display their average statistics data when they receive a SIGINT signal (control-c). The second one is again for pidstat: pidstat now displays the UID number for all tasks being monitored. A new option (-U) has also been added so that the name of the real user owning the task can be displayed instead of the UID.

Sunday December 23rd, 2012

Sysstat 10.1.3 released (development version).
This is mainly a bugfix release. What is worth noting here is the format change for network and IPv4/IPv6 counters which are now 64-bit wide to keep in sync with current Linux kernels. As a consequence this breaks compatibility with older sar data files format for those statistics (and only those ones).
OK. Pick it up from under the Christmas tree and enjoy...

Saturday October 6th, 2012

Sysstat 10.1.2 released (development version).
Two new metrics have been added here: the time spent by processors running a niced guest (displayed as "%gnice" by sar -u and mpstat) and the amount of memory waiting to get written back to disk (displayed as "kbdirty" by sar -r). This version also includes support for "systemd", the system and service manager intended to replace the init daemon for Linux.

Sunday July 29th, 2012

Sysstat 10.1.1 released (development version).
Big thanks go to Peter Schiffer from Redhat for his contribution to this version, the first one of a new development series. One of his patches adds persistent device names support to sar and iostat. As a consequence it is now possible to display (and specify) a device using his label, UUID, or any other type for which a directory is present in /dev/disk. Unrelated to this, I have also added a new way to tell sar from which daily data file he should display stats. Before you had to use something like "sar -f /var/log/sa/saDD [...]". It's now possible to enter "sar -1 [...]" to display stats from the daily data file of yesterday. Of course you can enter any number (-3, -12, etc.) to show data of that days ago. Full changelog available from the download page. Have fun :-)

Wednesday May 16th, 2012

Sysstat 10.0.5 released (stable version).
An interesting new feature has been added to iostat here: iostat can now display consolidated statistics for one or several groups of devices. This should prove useful for machines with lots of disks. Apart from that, this version includes some bug fixes for sadc and sadf, and a new translation file for Croatian people.

Wednesday March 7th, 2012

Sysstat 10.0.4 released (stable version).
This version includes bugfixes for sar and iostat: Virtual devices are no longer taken into account in sar -b results, and iostat can now display target device information when a symbolic link is specified as a parameter. A new option (--disable-stripping) has also been added to configure to tell it to not strip object files. Last, NLS has been updated with the addition of Serbian translation.

Sunday November 27th, 2011

Sysstat 10.0.3 released (stable version).
The main change in version 10.0.3 is the addition of JSON (JavaScript Object Notation) output format to sadf. This format is easy to read but less verbose than XML. Try it with "sadf -j /your/sar/datafile".

Sunday August 28th, 2011

Sysstat 10.0.2 released (stable version).
No new groundbreaking features in this release (hey, this is a stable series!) sadf has been heavily modified to make it easier to add new report formats later. I'm not very happy with the result anyway as its design is still not completely generic. Apart from that, a new option ("-P ON") has been added to mpstat. It indicates that statistics should be displayed only for online processors.

Friday June 3rd, 2011

Sysstat 10.0.1 released (stable version).
A new feature has been added to sar in this version. It can now take a snapshot of all the USB devices currently plugged into the system. Although this is a discrete monitoring process by nature, it should help the sys admins to detect the introduction of USB storage devices (eg. external hard drives, flash drives, thumb drives...) and close some potential security vulnerabilities. This version also includes the usual bunch of bugfixes (sar, sadf, cifsiostat...) Just go to the download page and enjoy!

Tuesday March 15th, 2011

Sysstat 10.0.0 released (stable version).
This is mainly a bugfix release. Several bugs have been fixed in nfsiostat and cifsiostat commands (thanks go to Masanari IIda for reporting them and Ivana Varekova from Redhat for fixing them). Also worth noting is that only sadc is now linked with lm_sensors library when needed. Read the full changelog to know all the changes included in this version.

Sunday December 26th, 2010

Sysstat 9.1.7 released (development version).
OK. So I took my Santa Claus dress to put this new version of sysstat under the Christmas tree. This one includes some new metrics for sar (amount of active and inactive memory, processes blocked waiting for I/O to complete) and also various optimizations and improvements. This should be the last version from the development series ; expect version 10.0.0 to be released around the month of February. Enjoy!

Wednesday November 10th, 2010

Sysstat 9.1.6 released (development version).
Lots of changes in this version. First, new metrics have been added to sar and sadc: These are hugepages utilization statistics, and average CPU clock frequency. To get the latter, you will need the cpufreq-stats driver compiled in your kernel. Then you should note that, after two years and a half of backward compatibility, this version breaks the format of sar daily data files again. This was made necessary for the inclusion of average CPU clock frequency. So I also took advantage of this to add a "compatibility marker" for each activity available in file, so that a future change concerning one activity only hits this activity and not the whole file.

Sunday September 12th, 2010

Sysstat 9.1.5 released (development version).
Other new metrics have been added to the power management group of statistics again. In particular this version adds voltage inputs stats to sar data. Please test it!

Thursday July 29th, 2010

Sysstat 9.1.4 released (development version).
New metrics have been added to the power management group of statistics in sar (patch from Jan Kaluza from Redhat). This version enables you to monitor fans speed and devices temperature. You will need the libsensors library (part of the lm_sensors project) installed for that.

Sunday June 27th, 2010

Sysstat 9.1.3 released (development version).
Lots of new features in this release. Two new commands have been added (nfsiostat and cifsiostat) enabling the user to display I/O statistics for NFS and CIFS filesystems (courtesy Ivana Varekova from Redhat). Other improvements concern mainly pidstat: It's now possible to select tasks using a regular expression with option -C. A new option has also been added to pidstat to display stack statistics (patch by Mario Konrad).

Sunday May 23rd, 2010

Sysstat 9.1.2 released (development version).
New fields have been added to iostat's extended statistics, giving the average time for read and write requests to be served (thanks go to Jérôme Marchand from Redhat for his help with that). Note that those fields should not be mistaken for read and write service times as they also include the time spent by the requests in queue... Also with this version, tickless CPUs will no longer be displayed as offline processors, but as 100% idle ones.

Sunday February 28th, 2010

Sysstat released (stable version).
Sysstat 9.1.1 released (development version).

More than 3 months have passed since the last sysstat release. After more than 10 years spent working on sysstat, I still certainly enjoy working on this project although a wife and two children have now made it a bit more difficult... Even if things go much more slowly now, I decided to start a new development series, so here is version 9.1.1, ready for you to test. See the release notes available from the download page. Note that from now on, sysstat will no longer support kernels older than 2.6. This enabled me to get rid of many lines of code...

Wednesday November 11th, 2009

Sysstat 9.0.6 released (stable version).
Apart from small bug fixes, this version improves the use of sadf with its -x option (displaying XML output): it is now possible to specify a starting and ending time with options -s and -e. Interval and count parameters are also taken into account by sadf -x. Oh, and this version also includes a new tool (sargraph) from Lans Carstensen to make graphs based on XML output from sadf!