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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.


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!

Sunday September 20th, 2009

Sysstat 9.0.5 released (stable version).
With this version, sysstat can now pretty-print device names whose minor numbers are greater than or equal to 256. This should prove useful especially on large Linux clusters.

Sunday July 19th, 2009

Sysstat 9.0.4 released (stable version).
This version fixes a nasty memory corruption bug in sadc. Huge thanks to Jonathan Kamens for pinpointing it. Apart from that, other changes here are really small stuff.

Sunday May 24th, 2009

Sysstat 9.0.3 released (stable version).
Various trivial changes or small improvements have been added here. They concern iostat, mpstat, sar, sadf, you name it. See the full changelog available from the download page to know all the details.

Thursday April 2nd, 2009

Sysstat 9.0.2 released (stable version).
More bug fixes and improvements in this version: A memory corruption has been fixed in iostat and pidstat, where a segfault could happen when a list of comma-separated values following option -p was entered on the command line. With regard to improvements, sadc can now collect partition statistics in addition to disk ones. Go on testing, as I want sysstat 9.0.x to become rock solid...!

Sunday March 7th, 2009

Sysstat 9.0.1 released (stable version).
Yep... This is my brown-paper-bag release, as this one mainly fixes a crash with the sar command, where a pointer was freed twice. Please upgrade!

Sunday March 1st, 2009

Sysstat 9.0.0 released (stable version).
OK. I said that there would be another development version (8.1.9). I lied. Well, I had in mind to add several metrics related to power management (CPU temperature, fan speed, etc.) It turned out to be more difficult than what I had imagined (yes, I need help for this... Any volunteer out there?) As a consequence, only CPU frequency statistics have been added to sar here. Anyway here is 9.0.0, the first version of a new, long-awaited, stable series!

Sunday January 11th, 2009

Sysstat 8.1.8 released (development version).
This version adds support for IPv6-related protocols (IPv6, TCPv6, ICMPv6, UDPv6) and a bunch of new metrics for sar. Sysstat 8.1.8 also includes various fixes and improvements for iostat. See the full changelog available from the download page. Note that there should be a last development version (8.1.9) before switching to the stable series (9.0.x). Enjoy!

Thursday November 13th, 2008

Sysstat 8.1.7 released (development version).
A major feature has been added to sar in this version: sar has now support for SNMPv2 statistics. Lots of new metrics have been added so that the user can now monitor IP, TCP, ICMP and UDP network traffic. Other changes in this version include the addition of option -l to pidstat to display the whole command line for each task.

Tuesday September 30th, 2008

Sysstat 8.1.6 released (development version).
This version includes improvements and bug fixes mainly for pidstat and mpstat commands. I hope then to begin adding SNMP statistics to sar in next sysstat version. So the development series will go on for a while.

Monday July 14th, 2008

Sysstat 8.1.5 released (development version).
New interesting features have been added in this version. First, sysstat and its commands sar, mpstat and pidstat have now support for virtual machine time accounting: They can display the time spent by the CPU to run a virtual processor or the time spent by a process in the virtual machine. New metrics have also been added to sar: In particular the amount of memory needed for current workload is now collected. This can prove useful to track possible OOM conditions.

Sunday June 22nd, 2008

Sysstat 8.1.4 released (development version).
This version includes a bunch of patches that I had put in my fridge for the past few months. I have also added back a feature that I had removed from sar in previous sysstat version. This feature (number of interrupts per processor) is now available with mpstat and its option "-I CPU".

Sunday May 25th, 2008

Sysstat 8.1.3 released (development version).
Here is the long awaited second technical release of sysstat. Although it doesn't add new features, the sar, sadc and sadf commands have been largely rewritten in a non-monolithic way with a generic design architecture. It will now be much simpler to add new system metrics (the so-called "activities") to get a wider insight into your Linux system. Expected results are performance analysis and tuning made easier for system administrators.

Sunday March 16th, 2008

Sysstat 8.1.2 released (development version).
OK. This version should have been the second (and last) technical release, but in fact, it's not. There is really too much work left to do, and completing it should still take one or two months(*). So I made 8.1.2 available, which includes new features mainly for iostat and sadf commands.
(*) For those of you who are wondering what kind of changes this next technical release is about, let's say that it will be a major rewriting of sar and sadc...

Sunday February 10th, 2008

Sysstat 8.1.1 released (development version).
Sysstat 8.1.1 should be considered mainly as a technical release: Data files created by sar have now additional information in their header (sysstat version used to create them, machine architecture...), error messages have been improved and made more explicit, source code have been reworked (large functions split into smaller ones, comments added,...). See the changelog for all the details. Note that next sysstat version will also be a technical release, and you will probably have to wait for version 8.1.3 planned for April to see (plenty of) new features being merged again.

Sunday January 6th, 2008

Sysstat 8.0.4 released (stable version).
This version adds minor feature enhancements. It also includes a new XML Schema that can be used to check the XML output generated by "sadf -x". This version of sysstat is intended to be the last one of the stable 8.0 series. The next development series will start soon and I have a bunch of exciting new features that I plan to add in the coming months...

Sunday November 18th, 2007

Sysstat 8.0.3 released (stable version).
You will find still more bug fixes in this version: First, the pidstat command made sometimes a confusion between PID and TID, resulting in erroneous statistics values being displayed. This version also fixes a problem with hotplug CPU support which made sar and mpstat parse /proc/interrupts sometimes incorrectly when some CPUs were set offline. Give this version a good try to see if there are any pending problems because I would like this stable series to become really rock solid...

Friday October 26th, 2007

Sysstat 8.0.2 released (stable version).
This version of sysstat adds a new option to pidstat (-w) enabling you to display per task switching activity (number of voluntary and involuntary context switches per second), providing that you have a recent Linux kernel (2.6.23+). Also some annoying bugs have been fixed here: a memory leak in pidstat which made its option -t display only headers after a few iterations, and a problem with device names displayed by sar.

Sunday September 30th, 2007

Sysstat 8.0.1 released (stable version).
In this version the pidstat command has been greatly improved with the addition of a new option that enables it to display statistics for every thread managed by the system. Also "pidstat -T CHILD" works now a bit differently: It reports global statistics for the selected tasks and all their children (and not statistics for the children only).

Sunday September 2nd, 2007

Sysstat 8.0.0 released (stable version).
This version is a stable one, which means that sar's data files format should no longer change for a while. Sysstat 8.0.0 includes several important changes: First, the pidstat command (which appeared in sysstat version 7.1.4) is now able to display CPU and page fault statistics for the child processes of a task. Then, some statistics that were previously gathered by sar from kernel tables (sar -v) have been removed since they had been made obsolete in 2.6 kernels. On the other hand sar now collects new stats like the number of pseudo-terminals in use (sar -v) or the number of sockets in TIME_WAIT state (sar -n SOCK). Last, this version of sysstat also fixes a security flaw in its startup script (CVE-2007-3852). Read the release notes available from the download page to know all the bug fixes and improvements included in this version.

Sunday July 8th, 2007

Sysstat 7.1.6 released (development version).
New metrics have been added to sar in this version. They concern virtual memory and should be useful for all of you wanting to get a more detailed insight into Linux memory management. This version also includes the usual set of bugfixes. Enjoy!

Saturday June 9th, 2007

Sysstat 7.1.5 released (development version).
At last, this version includes a long awaited feature: per-process I/O statistics, that you can now display with the pidstat command and its new option -d. Of course, you will need a recent Linux kernel for that (2.6.20+). Also with this sysstat version, it is now possible to insert a timestamped comment in the binary data file created by sar/sadc. This may be helpful to automate some performance tests...

Sunday April 29th, 2007

Sysstat 7.1.4 released (development version).
This version of sysstat adds a new command (pidstat) aimed at reporting statistics for Linux tasks (processes). This command will replace sar's options -x and -X and will have many more features (e.g. I plan to add per-process I/O statistics in next sysstat release).
Another change in this version which is worth being noted is the addition of option -N to iostat. This option enables the user to query any device-mapper devices for their registered device name. It should prove useful for viewing LVM2 statistics.

Tuesday March 27th, 2007

Sysstat 7.1.3 released (development version).
In this release you will find numerous bug fixes and improvements. Changes concern hotplug CPU support, support for keeping sar logfiles for more than one month, configuration script, isag, you name it. So please give it a good testing and tell me if anything goes wrong.

Sunday March 4th, 2007

Sysstat 7.1.2 released (development version).
OK. Here is yet another version of sysstat which includes various small improvements. Among others, sysstat now has better hotplug CPU support: It no longer assumes that CPU#0 can never be disabled. Also sar datafiles format has changed to become a little more compact.

Wednesday February 21st, 2007

Sysstat 7.1.1 released (development version).
The development cycle starts again with this version.  This one includes support for autoconf (thanks to Ivana Varekova from RedHat for that). Configuring sysstat is now done with the well known "./configure" script. But for those of you who might miss the old interactive configuration process, I have added "iconfig", a front-end to "configure" which enables you to set parameters values interactively.

Sunday February 4th, 2007

Sysstat 7.0.4 released (stable version).
This one should be the last version of the stable 7.0 series. With this version, the user will be able to keep sar data for more than one month (thanks to John Caruso for the original idea). This version also fixes a compilation problem on GNU/kFreeBSD.

Sunday December 3rd, 2006

Sysstat 7.0.3 released (stable version).
With this version, iostat is now able to display I/O statistics for network filesystems (NFS). This is a major improvement for iostat but which will require a recent kernel to work (2.6.17 or later).

Sunday October 22nd, 2006

Sysstat 7.0.2 released (stable version).
This version mainly includes a new important feature: support for hotplug CPU's. Sar and mpstat are now able to detect disabled processors and to display their data when they are set online.

Sunday September 17th, 2006

Sysstat 7.0.1 released (stable version).
Some more small improvements and bug fixes in this new version. For example I changed the way sadf considered the time entered on the command line with -s and -e options, so that sadf output is now always consistent with that of sar. See the changelog available from the download page to know the other changes.

Sunday July 9th, 2006

Sysstat 7.0.0 released (stable version).
OK. This is the beginning of a new stable series again for sysstat. I hope to make it last a bit so that sysstat may have the time to become rock solid. In this version sar takes into account a new environment variable that tells sar to use UTC to save its data and determine its current daily data file. This should prove useful for servers with users located across several timezones. Also this version now uses sysconf() system call to get the number of ticks per second, which should be the right way to do it...

Thursday June 1st, 2006

My Internet provider changed its name from Wanadoo to Orange. My mail address remains unchanged for the moment, but this web site is now at Please update your bookmarks!