List:General Discussion« Previous MessageNext Message »
From:Dan Nelson Date:March 9 2005 11:19pm
Subject:Re: Query_cache_size Question
View as plain text  
In the last episode (Mar 09), Mauricio Pellegrini said:
> Thanks,  this the result of show status like "qcache%"
> 
> +-------------------------+----------+
> | Variable_name           | Value    |
> +-------------------------+----------+
> | Qcache_free_blocks      | 3330     |
> | Qcache_free_memory      | 13372320 |
> | Qcache_hits             | 11119149 |
> | Qcache_inserts          | 1942009  |
> | Qcache_lowmem_prunes    | 372898   |
> | Qcache_not_cached       | 508528   |
> | Qcache_queries_in_cache | 3160     |
> | Qcache_total_blocks     | 9711     |
> +-------------------------+----------+
> 
> Am I right at saying that the value (16Mb)is ok ?
> 
> Qcache_not_cached means the number of query results that didn't get
> into the cache because of a space limitation ?  If so, perhaps adding
> few more Mb would improve that number , isn't it?

Yes; qcache_lowmem_prunes is a good indicator that raising
query_cache_size may help.  It counts the number if times the cache had
to be aged to free up space to cache a new resultset.  See the
documentation at http://dev.mysql.com/doc/mysql/en/query-cache.html for
more tuning ideas.

-- 
	Dan Nelson
	dnelson@stripped
Thread
Query_cache_size QuestionMauricio Pellegrini9 Mar
  • Re: Query_cache_size QuestionDan Nelson9 Mar
    • Re: Query_cache_size QuestionMauricio Pellegrini9 Mar
      • Re: Query_cache_size QuestionJocelyn Fournier10 Mar
        • Re: Query_cache_size QuestionMauricio Pellegrini10 Mar
          • Re: Query_cache_size QuestionJocelyn Fournier10 Mar
      • Re: Query_cache_size QuestionDan Nelson10 Mar
RE: Query_cache_size QuestionKostas Pyliouras9 Mar