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To: felix <crucialfelix@gmail.com>, "Scott Marlowe" <scott.marlowe@gmail.com>
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Subject: Re: Really really slow select count(*)
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>> I have clustered that table, its still unbelievably slow.
>
> Did you actually delete the old entries before clustering it?  if it's
> still got 4G of old sessions or whatever in it, clustering ain't gonna
> help.

Also, IMHO it is a lot better to store sessions in something like  
memcached, rather than imposing this rather large load on the main  
database...

PS : if your site has been down for 6 hours, you can TRUNCATE your  
sessions table...