vmstat i/o time shows 0 IO
From: Netocrat <firstname.lastname@example.org>
Subject: Re: Why am I not using 100% of cpu?
Date: Thu, 18 Aug 2005 22:56:36 +1000
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On Thu, 18 Aug 2005 09:01:34 -0400, Dave Sill wrote:
> Netocrat <email@example.com> writes:
>> Do you mean top or vmstat? In another post you wrote that the output was
>> from vmstat, in which case perhaps your kernel version is too old.
> Both top and vmstat.
>> From the vmstat manpage:
>> wa: Time spent waiting for IO. Prior to Linux 2.5.41, shown as zero.
> Well, that's bogus. If they're not reporting valid data, they should
> make it look like valid data. If they'd used a dash instead of a 0,
> I'd have known what was going on. Thanks for pointing that out.
> So now the question is: is I/O wait time counted as idle/system/user
> time, or is it just not counted at all?
I forgot to include the preceding line which would have made a difference;
here they both are:
id: Time spent idle. Prior to Linux 2.5.41, this includes IO-wait time.
wa: Time spent waiting for IO. Prior to Linux 2.5.41, shown as zero.
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