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From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
To: Andrew Dunstan <andrew@dunslane.net>
Subject: Re: Can't find thread on Linux memory overcommit
Date: Thu, 21 Aug 2003 10:13:26 -0700
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References: <200308201102.37559.josh@agliodbs.com>
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Cc: pgsql-hackers@postgresql.org
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Message-Id: <200308211013.26737.josh@agliodbs.com>

Alan,

> You need to be careful using Alan's patch. The reason RH stopped using
> this part of it in their errata kernels is that it had conflicts with
> other stuff, specifically the rmap stuff (he told me that himself in
> email).

Hmmm ... that leaves us without a workaround for this problem, then, yes?  
Because even parnoid-mode kernels you can discourage, but not prevent, 
overcommitting.

> For mission critical apps I would advise running the postmaster on a
> dedicated machine, with no X or other nasty stuff running.

Unfortunately, this is frequently not an option ... PostgreSQL is often 
together on a server with Apache, a JVM, and other server software.   As 
happened in the one case of possible (diagnosis pending) failure that we are 
looking into.  Of course, it could be something else ....

-- 
Josh Berkus
Aglio Database Solutions
San Francisco