From: Lazaro Garcia <lazaro3487@gmail.com>
To: 'David G. Johnston' <david.g.johnston@gmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: Help with bad performance with synchronous commit
Date: Mon, 3 Apr 2017 12:54:11 -0400
Message-ID: <002901d2ac9a$ef691cb0$ce3b5610$@gmail.com> (raw)
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Thanks for the reply:
pgbench -U postgres -p 6432 -j 10 -c 500 -T 60 -h localhost -P 2 pgbench (write test)
I have uninstalled 9.6 and installed postgresql 9.5.6 from Ubuntu repos. These was de new results:
transaction type: TPC-B (sort of)
scaling factor: 200
query mode: simple
number of clients: 500
number of threads: 10
duration: 60 s
number of transactions actually processed: 236733 latency average: 126.187 ms latency stddev: 152.347 ms tps = 3919.425981 (including connections establishing) tps = 3919.945554 (excluding connections establishing)
2 days later the test throws less results but constant.
transaction type: TPC-B (sort of)
scaling factor: 200
query mode: simple
number of clients: 500
number of threads: 10
duration: 60 s
number of transactions actually processed: 76788 latency average: 394.308 ms tps = 1268.044488 (including connections establishing) tps = 1268.124718 (excluding connections establishing)
The iowait was between 15 and 25 percet when the test was runing:
Is there any way to identify the cause of this differences?
How can I configure commit_delay and commit_siblings properly?
These are disk details:
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To: pgsql-admin@postgresql.org
Cc: lazaro3487@gmail.com, david.g.johnston@gmail.com
Subject: Re: Help with bad performance with synchronous commit
In-Reply-To: <002901d2ac9a$ef691cb0$ce3b5610$@gmail.com>
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