From: | Justin Clift <justin(at)postgresql(dot)org> |
---|---|
To: | shridhar_daithankar(at)persistent(dot)co(dot)in |
Cc: | pgsql-hackers(at)postgresql(dot)org, pgsql-general(at)postgresql(dot)org |
Subject: | Re: Performance while loading data and indexing |
Date: | 2002-09-26 09:17:32 |
Message-ID: | 3D92D0AC.CE6114C4@postgresql.org |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general pgsql-hackers pgsql-performance |
Hi Shridhar,
Shridhar Daithankar wrote:
<snip>
> 3) Any suggsestions for runtime as data load and query will be going in
> parallel.
That sounds unusual. From reading this, it *sounds* like you'll be
running queries against an incomplete dataset, or maybe just running the
queries that affect the tables loaded thus far (during the initial
load).
<snip>
> fsync=true (Sad but true. Left untouched.. Will that make a difference on
> SCSI?)
Definitely. Have directly measured a ~ 2x tps throughput increase on
FreeBSD when leaving fsync off whilst performance measuring stuff
recently (PG 7.2.2). Like anything it'll depend on workload, phase of
moon, etc, but it's a decent indicator.
<snip>
> Now questions.
>
> 1) Instead of copying from a single 12GB data file, will a parallel copy from
> say 5 files will speed up the things?
Not sure yet. Haven't get done enough performance testing (on the cards
very soon though).
> Couple MB of data per sec. to disk is just not saturating it. It's a RAID 5
> setup..
fsync = off would help during the data load, but not a good idea if
you're going to be running queries against it at the same time.
Am still getting the hang of performance tuning stuff. Have a bunch of
Ultra160 hardware for the Intel platform, and am testing against it as
time permits.
Not as high end as I'd like, but it's a start.
:-)
Regards and best wishes,
Justin Clift
<snip>
> 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
From | Date | Subject | |
---|---|---|---|
Next Message | Mario Weilguni | 2002-09-26 09:17:50 | Re: Performance while loading data and indexing |
Previous Message | Shridhar Daithankar | 2002-09-26 09:13:20 | Re: Performance while loading data and indexing |
From | Date | Subject | |
---|---|---|---|
Next Message | Mario Weilguni | 2002-09-26 09:17:50 | Re: Performance while loading data and indexing |
Previous Message | Shridhar Daithankar | 2002-09-26 09:13:20 | Re: Performance while loading data and indexing |
From | Date | Subject | |
---|---|---|---|
Next Message | Shridhar Daithankar | 2002-09-26 09:35:40 | Re: Performance while loading data and indexing |
Previous Message | Shridhar Daithankar | 2002-09-26 09:13:20 | Re: Performance while loading data and indexing |