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Subject: Re: [2.4.17/18pre] VM and swap - it's really unusable
From: Robert Love <rml@tech9.net>
To: Andrew Morton <akpm@zip.com.au>
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On Sun, 2002-01-13 at 14:46, Andrew Morton wrote:

> I can't say that I have ever seen any significant change in throughput
> of anything with any of this stuff.

I can send you some numbers.  It is typically 5-10% throughput increase
under load.  Obviously this work won't help a single task on a single
user system.  But things like (ack!) dbench 16 show a marked
improvement.

> Benchmarks are well and good, but until we have a solid explanation for
> the throughput changes which people are seeing, it's risky to claim
> that there is a general benefit.

I have an explanation.  We can schedule quicker off a woken task.  When
an event occurs that allows an I/O-blocked task to run, its time-to-run
is shorter.  Same event/response improvement that helps interactivity.

	Robert Love

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