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SubjectRe: ALLANC: Proposal to add progress records to process accounting
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> Are you planning to update the log based upon wall time or cpu used ?

I planned on using the exact same algorithm as is used currently. I believe
the current->signal->pacct structure holds system and user CPU time which
is copied into the log ac_stime and ac_utime entries respectively in
kernel/acct.c/do_acct_proces() thus:
ac.ac_utime =
encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
ac.ac_stime =
encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));

The log ac_etime is elapsed time (which is what I assume you mean by wall
time) and is calculated as current_uptime - process_start_time
(paraphrased) in the same function.

Cheers,
Pax.
==========
Two strings walk into a bar. The first one says: "Hello, I'd like some
Vodka please.ytewsr@)W$(#*$&!^Y@)^&30@#!".
"You'll have to excuse my friend," the second one says, "he's not
null-terminated".
==========
Allan Chandler (Pax), Senior IT Specialist, Australia Development
Laboratory (ADL), Perth, IBM Corporation
Internet: allachan@au1.ibm.com, Phone: +61 8 926 13019, Fax: +61 8 921
89201
Location code MP25, 77 St George's Terrace (Allendale Square), Level 25,
Perth WA 6000
_______________________________________________



Alan Cox
<alan@lxorguk.uku
u.org.uk> To
Sent by: Allan Chandler/Australia/IBM@IBMAU
linux-kernel-owne cc
r@vger.kernel.org linux-kernel@vger.kernel.org
Subject
Re: ALLANC: Proposal to add
13/01/2009 06:17 progress records to process
PM accounting










> will be written for any process that hasn't written a record in a while
> (for our purposes, 24 hours is fine but it may be better to make this
> configurable).

Agreed and this sounds sensible.

> too much overhead to the context switch (that's putting it mildly). I
> assume this would be somewhere in kernel/sched.c/context_switch() or
> kernel/sched.c/prepare_task_switch() although I haven't yet looked in
great
> detail.

Are you planning to update the log based upon wall time or cpu used ?

Alan





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