Re: Help understanding slow down

William Lee Irwin III
2004-05-24T01:28:44Z

On Mon, May 24, 2004 at 03:25:53AM +0200, Jakob Oestergaard wrote:
> Eh, not if I read the numbers right:
> 2.6.7-p1: 24.86user 51.77system 2:58.87elapsed 42%CPU
> 24.86 + 51.77 = 76.63 seconds on CPU, 102.24 seconds of waiting
> 2.4.21: 28.68user 34.98system 1:12.34elapsed 87%CPU
> 28.68 + 34.98 = 63.66 seconds on CPU, 8.68 seconds of waiting
> So, 2.6.7-p1 spends 16.79 seconds more in the kernel as you observed,
> but it spends 93.56 seconds more waiting for I/O (or whatever).
> Unless I'm totally missing something, the wait seems to be the
> regression.

I'm sorry, you're right. Let's start by looking into IO activity.
Phy, could you log the output of vmstat(1) during the runs?

-- wli