Skip site navigation (1) Skip section navigation (2)

Re: Inserting 8MB bytea: just 25% of disk perf used?

From: "fkater(at)googlemail(dot)com" <fkater(at)googlemail(dot)com>
To: Pierre Frédéric Caillaud <lists(at)peufeu(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Inserting 8MB bytea: just 25% of disk perf used?
Date: 2010-01-19 10:16:07
Message-ID: 20100119101607.GA2200@comppasch2 (view raw or flat)
Thread:
Lists: pgsql-performance
fkater(at)googlemail(dot)com:

> I'll try to execute these tests on a SSD
> and/or Raid system.

FYI:

On a sata raid-0 (mid range hardware) and recent 2x 1.5 TB
disks with a write performance of 100 MB/s (worst, to 200
MB/s max), I get a performance of 18.2 MB/s. Before, with
other disk 43 MB/s (worst to 70 MB/s max) postgres came to
14-16 MB/s.

So, I conclude finally:

(1) Postgresql write throughput (slowly) scales with the
harddisk speed.

(2) The throughput (not counting WAL doubling data) in
postgresql is 20-25% of the disk thoughput.


I want to thank you all for the very good support!

 Felix



In response to

Responses

pgsql-performance by date

Next:From: fkater@googlemail.comDate: 2010-01-19 10:50:07
Subject: Re: Inserting 8MB bytea: just 25% of disk perf used?
Previous:From: Ing. Marcos L. Ortiz ValmasedaDate: 2010-01-19 08:25:28
Subject: Re: renice on an I/O bound box

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group