Re: Add min and max execute statement time in pg_stat_statement - Mailing list pgsql-hackers

From KONDO Mitsumasa
Subject Re: Add min and max execute statement time in pg_stat_statement
Date
Msg-id 52E8B5EA.70301@lab.ntt.co.jp
Whole thread Raw
In response to Re: Add min and max execute statement time in pg_stat_statement  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Add min and max execute statement time in pg_stat_statement  (Magnus Hagander <magnus@hagander.net>)
List pgsql-hackers
(2014/01/29 15:51), Tom Lane wrote:
> KONDO Mitsumasa <kondo.mitsumasa@lab.ntt.co.jp> writes:
>> By the way, latest pg_stat_statement might affect performance in Windows system.
>> Because it uses fflush() system call every creating new entry in
>> pg_stat_statements, and it calls many fread() to warm file cache.
> This statement doesn't seem to have much to do with the patch as
> committed.  There are no fflush calls, and no notion of warming the
> file cache either.
Oh, all right.

> We do assume that the OS is smart enough to keep
> a frequently-read file in cache ... is Windows too stupid for that?
I don't know about it. But I think Windows cache feature is stupid.
It seems to always write/read data to/from disk, nevertheless having large memory...
I'd like to know test result on Windows, if we can...

Regards,
--
Mitsumasa KONDO
NTT Open Source Software Center





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