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From:Chris Date:January 16 2008 6:27am
Subject:Re: Does SQL_NO_CACHE work?
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mos wrote:
> I tried :
> select SQL_NO_CACHE * from table where col1='abc';
> which took 800ms the first time it was executed. The second time it was 
> executed it took 0ms. How is that possible if the query is not put into 
> the query cache? Should the query take roughly the same amount of time?

Disk cache.
The database table was still in memory.

The OS caches a lot of stuff too (file descriptors etc).

Try restarting mysql between runs and see if that's more consistent.
Does SQL_NO_CACHE work?mos16 Jan
  • Re: Does SQL_NO_CACHE work?Chris16 Jan
  • Re: Does SQL_NO_CACHE work?Dan Nelson16 Jan
    • Re: Does SQL_NO_CACHE work?Moon's Father16 Jan