Mel Gorman db9e5679d6 delay-accounting: reimplement -c for getdelays.c to report information on a target command ... 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>		2010-10-27 18:03:17 -07:00
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.gitignore	.gitignore updates	2008-10-30 11:38:45 -07:00
cgroupstats.txt
delay-accounting.txt	per-task-delay-accounting: update document and getdelays.c for memory reclaim	2008-07-25 10:53:47 -07:00
getdelays.c	delay-accounting: reimplement -c for getdelays.c to report information on a target command	2010-10-27 18:03:17 -07:00
Makefile	docsrc: build Documentation/ sources	2008-08-12 16:07:30 -07:00
taskstats-struct.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
taskstats.txt