Re: [HACKERS] Performance while loading data and indexing - Mailing list pgsql-general

From Justin Clift
Subject Re: [HACKERS] Performance while loading data and indexing
Date
Msg-id 3D92D9D2.64CF55F7@postgresql.org
Whole thread Raw
In response to Performance while loading data and indexing  ("Shridhar Daithankar" <shridhar_daithankar@persistent.co.in>)
Responses Re: [HACKERS] Performance while loading data and indexing  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Shridhar Daithankar wrote:
>
> On 26 Sep 2002 at 19:05, Martijn van Oosterhout wrote:
<snip>
> > fsync IIRC only affects the WAL buffers now but it may be quite expensive,
> > especially considering it's running on every transaction commit. Oh, your
> > WAL files are on a seperate disk from the data?
>
> No. Same RAID 5 disks..

Not sure if this is a good idea.  Would have to think deeply about the
controller and drive optimisation/load characteristics.

If it's any help, when I was testing recently with WAL on a separate
drive, the WAL logs were doing more read&writes per second than the main
data drive.  This would of course be affected by the queries you are
running against the database.  I was just running Tatsuo's TPC-B stuff,
and the OSDB AS3AP tests.

> I guess we forgot to monitor system parameters. Next on my list is running
> vmstat, top and tuning bdflush.

That'll just be the start of it for serious performance tuning and
learning how PostgreSQL works.  :)

<snip>
> Thanks once again...
> Bye
>  Shridhar

--
"My grandfather once told me that there are two kinds of people: those
who work and those who take the credit. He told me to try to be in the
first group; there was less competition there."
   - Indira Gandhi

pgsql-general by date:

Previous
From: Patrick Welche
Date:
Subject: Re: Relation 0 does not exist
Next
From: Richard Huxton
Date:
Subject: Re: Performance while loading data and indexing