From: Luke Lonergan <llonergan@greenplum.com>
To: Mark Wong <markw@osdl.org>
Cc: Andrew Dunstan <andrew@dunslane.net>
Cc: Alvaro Herrera <alvherre@surnet.cl>
Cc: Bruce Momjian <pgman@candle.pha.pa.us>
Cc: Alon Goldshuv <agoldshuv@greenplum.com>
Cc: pgsql-patches@postgresql.org
Cc: maryedie@osdl.org
Subject: Re: COPY FROM performance improvements
Date: Thu, 21 Jul 2005 16:14:47 -0700
Message-ID: <BF057A77.96D7%llonergan@greenplum.com> (raw)
In-Reply-To: <200507212154.j6LLsdjA002847@smtp.osdl.org>
Cool!
At what rate does your disk setup write sequential data, e.g.:
time dd if=/dev/zero of=bigfile bs=8k count=500000
(sized for 2x RAM on a system with 2GB)
BTW - the Compaq smartarray controllers are pretty broken on Linux from a
performance standpoint in our experience. We've had disastrously bad
results from the SmartArray 5i and 6 controllers on kernels from 2.4 ->
2.6.10, on the order of 20MB/s.
For comparison, the results on our dual opteron with a single LSI SCSI
controller with software RAID0 on a 2.6.10 kernel:
[llonergan@stinger4 dbfast]$ time dd if=/dev/zero of=bigfile bs=8k
count=500000
500000+0 records in
500000+0 records out
real 0m24.702s
user 0m0.077s
sys 0m8.794s
Which calculates out to about 161MB/s.
- Luke
On 7/21/05 2:55 PM, "Mark Wong" <markw@osdl.org> wrote:
> I just ran through a few tests with the v14 patch against 100GB of data
> from dbt3 and found a 30% improvement; 3.6 hours vs 5.3 hours. Just to
> give a few details, I only loaded data and started a COPY in parallel
> for each the data files:
> http://www.testing.osdl.org/projects/dbt3testing/results/fast_copy/
>
> Here's a visual of my disk layout, for those familiar with the database
> schema:
> http://www.testing.osdl.org/projects/dbt3testing/results/fast_copy/layout-dev4
> -010-dbt3.html
>
> I have 6 arrays of fourteen 15k rpm drives in a split-bus configuration
> attached to a 4-way itanium2 via 6 compaq smartarray pci-x controllers.
>
> Let me know if you have any questions.
>
> Mark
>
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: llonergan@greenplum.com, markw@osdl.org, andrew@dunslane.net, alvherre@surnet.cl, pgman@candle.pha.pa.us, agoldshuv@greenplum.com, pgsql-patches@postgresql.org, maryedie@osdl.org
Subject: Re: COPY FROM performance improvements
In-Reply-To: <BF057A77.96D7%llonergan@greenplum.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