Task delay-accounting was identified as one means of determining how long
a process spends in congestion_wait() without adding new statistics. For
example, if the workload should not be doing IO, delay-accounting could
reveal how long it was spending in unexpected IO or delays.
Unfortunately, on closer examination it was clear that getdelays does not
act as documented.
Commit a3baf649 ("per-task-delay-accounting: documentation") added
Documentation/accounting/getdelays.c with a -c switch that was documented
to fork/exec a child and report statistics on it but for reasons that are
unclear to me, commit 9e06d3f9 deleted support for this switch but did not
update the documentation. It might be an oversight or it might be because
the control flow of the program meant that accounting information would be
printed once early in the lifetime of the program making it of limited
use.
This patch reimplements -c for getdelays.c to act as documented. Unlike
the original version, it waits until the command completes before printing
any information on it. An example of it being used looks like
$ ./getdelays -d -c find /home/mel -name mel
print delayacct stats ON
/home/mel
/home/mel/.notes-wine/drive_c/windows/profiles/mel
/home/mel/.wine/drive_c/windows/profiles/mel
/home/mel/git-configs/dot.kde/share/apps/konqueror/home/mel
PID 5923
CPU count real total virtual total delay total
42779 5051232096 5164722692 564207988
IO count delay total
41727 97804147758
SWAP count delay total
0 0
RECLAIM count delay total
0 0
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix up -Wmissing-prototypes in compileable userspace code, mainly under
Documentation/.
Signed-off-by: Ladinu Chandrasinghe <ladinu.pub@gmail.com>
Signed-off-by: Trevor Keith <tsrk@tsrk.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix compilation warning:
Documentation/accounting/getdelays.c: In function `main':
Documentation/accounting/getdelays.c:249: warning: `cmd_type' may be used uninitialized in this function
This is in fact a false positive.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When no option is passed to getdelays it just hangs, waiting
for a reply which will never come.
This patch prints usage() when no output marker is specified.
Signed-off-by: Marcus Meissner <meissner@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix printf format type warnings (seen on alpha & ia64):
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 6 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 7 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 8 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 9 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 12 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 13 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 16 has type '__u64'
Documentation/accounting/getdelays.c:206: warning: format '%15llu' expects type 'long long unsigned int', but argument 17 has type '__u64'
Documentation/accounting/getdelays.c:214: warning: format '%15llu' expects type 'long long unsigned int', but argument 4 has type '__u64'
Documentation/accounting/getdelays.c:214: warning: format '%15llu' expects type 'long long unsigned int', but argument 5 has type '__u64'
Documentation/accounting/getdelays.c:221: warning: format '%llu' expects type 'long long unsigned int', but argument 2 has type '__u64'
Documentation/accounting/getdelays.c:221: warning: format '%llu' expects type 'long long unsigned int', but argument 3 has type '__u64'
Documentation/accounting/getdelays.c:221: warning: format '%llu' expects type 'long long unsigned int', but argument 4 has type '__u64'
Documentation/accounting/getdelays.c:221: warning: format '%llu' expects type 'long long unsigned int', but argument 5 has type '__u64'
Documentation/accounting/getdelays.c:221: warning: format '%llu' expects type 'long long unsigned int', but argument 6 has type '__u64'
Documentation/accounting/getdelays.c:236: warning: 'cmd_type' may be used uninitialized in this function
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently source files in the Documentation/ sub-dir can easily bit-rot
since they are not generally buildable, either because they are hidden in
text files or because there are no Makefile rules for them. This needs to
be fixed so that the source files remain usable and good examples of code
instead of bad examples.
Add the ability to build source files that are in the Documentation/ dir.
Add to Kconfig as "BUILD_DOCSRC" config symbol.
Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the
Documentation/ sources. Or enable BUILD_DOCSRC in the *config system.
However, this symbol depends on HEADERS_CHECK since the header files need
to be installed (for userspace builds).
Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32,
sparc64, powerpc, sh, m68k, & mips.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update document and make getdelays.c show delay accounting for memory reclaim.
For making a distinction between "swapping in pages" and "memory reclaim"
in getdelays.c, MEM is changed to SWAP.
Signed-off-by: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add members for memory reclaim delay to taskstats, and accumulate them in
__delayacct_add_tsk() .
Signed-off-by: Keika Kobayashi <kobayashi.kk@ncos.nec.co.jp>
Cc: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix gcc warnings in getdelays.c:
Documentation/accounting/getdelays.c: In function 'task_context_switch_counts':
Documentation/accounting/getdelays.c:214: warning: format '%15lu' expects type 'long unsigned int', but argument 4 has type '__u64'
Documentation/accounting/getdelays.c:214: warning: format '%15lu' expects type 'long unsigned int', but argument 5 has type '__u64'
Documentation/accounting/getdelays.c: In function 'main':
Documentation/accounting/getdelays.c:402: warning: format '%d' expects type 'int', but argument 2 has type 'long unsigned int'
Documentation/accounting/getdelays.c: In function 'get_family_id':
Documentation/accounting/getdelays.c:171: warning: 'id' may be used uninitialized in this function
One warning is not a problem and can be dismissed:
Documentation/accounting/getdelays.c: In function 'main':
Documentation/accounting/getdelays.c:236: warning: 'cmd_type' may be used uninitialized in this function
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update the getdelays utility to become cgroupstats aware. A new -C option has
been added. It takes in a control group path and prints out a summary of the
states of tasks in the control group
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is inspired by the discussion at
http://lkml.org/lkml/2007/4/11/187 and implements per cgroup statistics
as suggested by Andrew Morton in http://lkml.org/lkml/2007/4/11/263. The
patch is on top of 2.6.21-mm1 with Paul's cgroups v9 patches (forward
ported)
This patch implements per cgroup statistics infrastructure and re-uses
code from the taskstats interface. A new set of cgroup operations are
registered with commands and attributes. It should be very easy to
*extend* per cgroup statistics, by adding members to the cgroupstats
structure.
The current model for cgroupstats is a pull, a push model (to post
statistics on interesting events), should be very easy to add. Currently
user space requests for statistics by passing the cgroup file
descriptor. Statistics about the state of all the tasks in the cgroup
is returned to user space.
TODO's/NOTE:
This patch provides an infrastructure for implementing cgroup statistics.
Based on the needs of each controller, we can incrementally add more statistics,
event based support for notification of statistics, accumulation of taskstats
into cgroup statistics in the future.
Sample output
# ./cgroupstats -C /cgroup/a
sleeping 2, blocked 0, running 1, stopped 0, uninterruptible 0
# ./cgroupstats -C /cgroup/
sleeping 154, blocked 0, running 0, stopped 0, uninterruptible 0
If the approach looks good, I'll enhance and post the user space utility for
the same
Feedback, comments, test results are always welcome!
[akpm@linux-foundation.org: build fix]
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch cleans up duplicate includes in
Documentation/
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit b663a79c19 ("taskstats: add
context-switch counters") incorrectly removed a comma from a printf
statement. This causes corruption in the output printing or a seg
fault.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make available to the user the following task and process performance
statistics:
* Involuntary Context Switches (task_struct->nivcsw)
* Voluntary Context Switches (task_struct->nvcsw)
Statistics information is available from:
1. taskstats interface (Documentation/accounting/)
2. /proc/PID/status (task only).
This data is useful for detecting hyperactivity patterns between processes.
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Maxim Uvarov <muvarov@ru.mvista.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: Jonathan Lim <jlim@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A patch for getdelays.c that fixes a buffer overrun when you set -w.
Cc: <matt@bluehost.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add usage to getdelays.c. This patch was originally posted by Randy Dunlap
http://lkml.org/lkml/2007/3/19/168
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Various cleanups
- Report errors to stderr, not stdout
- A printf was missing a \n and was hiding from me.
Cc: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Cc: David Wright <daw@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letters 'U-Z'.
Looks like I made it through the alphabet...just in time to start over again
+too! Maybe I can fit more profound fixes into the next round...? Time will
+tell. :)
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
This patch fixes typos in various Documentation txts. The patch addresses some
+words starting with the letter 'T'.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
ChangeLog:
Feedbacks from Andrew Morton:
- define TS_COMM_LEN to 32
- change acct_stimexpd field of task_struct to be of
cputime_t, which is to be used to save the tsk->stime
of last timer interrupt update.
- a new Documentation/accounting/taskstats-struct.txt
to describe fields of taskstats struct.
Feedback from Balbir Singh:
- keep the stime of a task to be zero when both stime
and utime are zero as recoreded in task_struct.
Misc:
- convert accumulated RSS/VM from platform dependent
pages-ticks to MBytes-usecs in the kernel
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix the length passed while (un)registering cpumask. We were passing sizeof
the array, make it strlen().
Error value printed in fatal errors should be derived from the message. The
message contains an nlmsgerr embedded with an error value. We must report
that value to the user.
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jamal Hadi <hadi@cyberus.ca>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Enable delay accounting by default so that feature gets coverage testing
without requiring special measures.
Earlier, it was off by default and had to be enabled via a boot time param.
This patch reverses the default behaviour to improve coverage testing. It
can be removed late in the kernel development cycle if its believed users
shouldn't have to incur any cost if they don't want delay accounting. Or
it can be retained forever if the utility of the stats is deemed common
enough to warrant keeping the feature on.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change documentation and example program to reflect the flow control issues
being addressed by the cpumask changes.
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Send per-tgid data only once during exit of a thread group instead of once
with each member thread exit.
Currently, when a thread exits, besides its per-tid data, the per-tgid data
of its thread group is also sent out, if its thread group is non-empty.
The per-tgid data sent consists of the sum of per-tid stats for all
*remaining* threads of the thread group.
This patch modifies this sending in two ways:
- the per-tgid data is sent only when the last thread of a thread group
exits. This cuts down heavily on the overhead of sending/receiving
per-tgid data, especially when other exploiters of the taskstats
interface aren't interested in per-tgid stats
- the semantics of the per-tgid data sent are changed. Instead of being
the sum of per-tid data for remaining threads, the value now sent is the
true total accumalated statistics for all threads that are/were part of
the thread group.
The patch also addresses a minor issue where failure of one accounting
subsystem to fill in the taskstats structure was causing the send of
taskstats to not be sent at all.
The patch has been tested for stability and run cerberus for over 4 hours
on an SMP.
[akpm@osdl.org: bugfixes]
Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create a "taskstats" interface based on generic netlink (NETLINK_GENERIC
family), for getting statistics of tasks and thread groups during their
lifetime and when they exit. The interface is intended for use by multiple
accounting packages though it is being created in the context of delay
accounting.
This patch creates the interface without populating the fields of the data
that is sent to the user in response to a command or upon the exit of a task.
Each accounting package interested in using taskstats has to provide an
additional patch to add its stats to the common structure.
[akpm@osdl.org: cleanups, Kconfig fix]
Signed-off-by: Shailabh Nagar <nagar@us.ibm.com>
Signed-off-by: Balbir Singh <balbir@in.ibm.com>
Cc: Jes Sorensen <jes@sgi.com>
Cc: Peter Chubb <peterc@gelato.unsw.edu.au>
Cc: Erich Focht <efocht@ess.nec.de>
Cc: Levent Serinol <lserinol@gmail.com>
Cc: Jay Lan <jlan@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
