Re: random slow query

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Alan Hodgson wrote:
On Tuesday 30 June 2009, Mike Ivanov <mikei@xxxxxxxxxxxxxxx> wrote:
Hi Scott,

Well, we can't be sure OP's only got one core.
In fact, we can, Sean posted what top -b -n 1 says. There was only one
CPU line.


Recent versions of top on Linux (on RedHat 5 anyway) may show only one combined CPU line unless you break them out with an option.

I have not noticed that to be the case. I ran RHEL3 from early 2004 until a
little after RHEL5 came out. I now run that (updated whenever updates come
out), and I do not recall ever setting any flag to get it to split the CPU
into 4 pieces.

I know the flag is there, but I do not recall ever setting it.

the number of cores, it's the IO subsystem is too slow for the load.
More cores wouldn't fix that.
While I agree on the IO, more cores would definitely help to improve
~6.5 load average.

No, I agree with the previous poster. His load is entirely due to IO wait. Only one of those processes was trying to do anything. IO wait shows up as high load averages.

If you run xosview, you can see all that stuff broken out, in my case at
one-second intervals. It shows user, nice, system, idle, wait, hardware
interrupt, software interrupt.

It also shows disk read, write, and idle time.

Lots of other stuff too.

--
  .~.  Jean-David Beyer          Registered Linux User 85642.
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 /( )\ Shrewsbury, New Jersey    http://counter.li.org
 ^^-^^ 14:55:01 up 12 days, 1:44, 3 users, load average: 4.34, 4.36, 4.41

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