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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: pgsql-hackers@postgresql.org
Subject: Re: Protect syscache from bloating with negative cache entries
Date: Sat, 14 Jan 2017 01:36:18 +0100
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On 01/14/2017 12:06 AM, Andres Freund wrote:
> Hi,
>
>
> On 2017-01-13 17:58:41 -0500, Tom Lane wrote:
>> But, again, the catcache isn't the only source of per-process bloat
>> and I'm not even sure it's the main one.  A more holistic approach
>> might be called for.
>
> It'd be helpful if we'd find a way to make it easy to get statistics
> about the size of various caches in production systems. Right now
> that's kinda hard, resulting in us having to make a lot of
> guesses...
>

What about a simple C extension, that could inspect those caches? 
Assuming it could be loaded into a single backend, that should be 
relatively acceptable way (compared to loading it to all backends using 
shared_preload_libraries).


-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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  Subject: Re: Protect syscache from bloating with negative cache entries
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