From: Sören Meyer-Eppler <soerenme@google.com>
To: pgsql-performance@postgresql.org
Subject: PostgreSQL 9.0.4 blocking in lseek?
Date: Wed, 26 Oct 2011 17:47:08 +0200
Message-ID: <4EA82B7C.1040008@google.com> (raw)
We are running into a significant performance issue with
"PostgreSQL 9.0.4 on x86_64-pc-linux-gnu, compiled by GCC gcc-4.4.real
(Debian 4.4.5-8) 4.4.5, 64-bit"
(the version string pqAdmin displays).
A fairly complex insert query on an empty destination table will run for
an indefinite amount of time (we waited literally days for the query to
complete). This does not happen every time we run the query but often.
Now ordinarily I'd assume we did something wrong with our indices or
query, but the execution plan looks sane and, more tellingly, we have:
- no CPU load
- no network traffic
- no disk I/O
- no other load on the server except this single query
and strace displaying a seemingly endless list of lseek calls.
So my assumption is that we are not running into bad Big-O() runtime
behavior but rather into some locking problem.
Any ideas what might cause this? Workarounds we could try?
thank you,
Sören
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: soerenme@google.com
Subject: Re: PostgreSQL 9.0.4 blocking in lseek?
In-Reply-To: <4EA82B7C.1040008@google.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox