From: Date: July 4 2008 3:28am
Subject: Re: mutex contention for the query cache
List-Archive: http://lists.mysql.com/internals/35798
Message-Id: <559AED9C-8FF0-41AA-A12C-7F5EE675DE4F@tangent.org>
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Hi!

On Jul 3, 2008, at 2:05 PM, Sergei Golubchik wrote:

> extent query cache so that Maria would use exact visibility rules and
> maximize cache using - all transactions that could see the entry would
> see it, those that couldn't - wouldn't.

Well I will look forward to seeing how you solve that for Maria.

> Query cache as it's done now is dirt cheap (concurrency can be fixed).

I have some big doubts that this is the case. I think you will find  
that the lock methods being deployed right now around RW are not going  
to scale on any of the hardware we are seeing deployed. As is you will  
find that the general rule of thumb today is to just get rid of it.  
For anyone wanting to make use of the hardware that they are deploying  
the only solution is to junk it.

Cheers,
	-Brian

--
_______________________________________________________
Brian "Krow" Aker, brian at tangent.org
Seattle, Washington
http://krow.net/                     <-- Me
http://tangent.org/                <-- Software
_______________________________________________________
You can't grep a dead tree.