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From:Jeremy Zawodny Date:June 21 2004 6:28pm
Subject:Re: R: why CPU is high while disks are idle in a table scan???
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On Mon, Jun 21, 2004 at 07:10:59PM +0200, Leonardo Francalanci wrote:
> > Hard to say, but in a table scan the CPU does have a lot of work to
> > do.  It needs to do about 16,000,000 comparisons (based on your info).
> 
> Why comparison? It's a sum...

Oh.  You didn't say thta. :-)

> And the table is not small: 272,000,000 bytes!
> 
> And disk is very low (almost 0%)

How much RAM does your machine have?  If it's nearly all cached,
you'll be CPU bound rather than disk bound.

Jeremy
-- 
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Thread
why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
  • Re: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
    • R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
      • Re: R: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
        • R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
          • Re: R: R: why CPU is high while disks are idle in a table scan???Jeremy Zawodny21 Jun
  • Re: why CPU is high while disks are idle in a table scan???Brent Baisley21 Jun
    • R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci21 Jun
Re: R: why CPU is high while disks are idle in a table scan???SGreen21 Jun
  • R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci22 Jun
Re: R: R: why CPU is high while disks are idle in a table scan???SGreen22 Jun
  • R: R: R: why CPU is high while disks are idle in a table scan???Leonardo Francalanci22 Jun