Re: how to fix problem then when two queries run at the same time, it takes longer to complete then if run in sequence

From: "Scott Marlowe" <scott(dot)marlowe(at)gmail(dot)com>
To: Miernik <public(at)public(dot)miernik(dot)name>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: how to fix problem then when two queries run at the same time, it takes longer to complete then if run in sequence
Date: 2008-07-23 20:43:25
Message-ID: dcc563d10807231343x5d07acdfu85d3eba3ec6afc3@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-performance

On Wed, Jul 23, 2008 at 2:32 PM, Miernik <public(at)public(dot)miernik(dot)name> wrote:
> Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com> wrote:
>> won't ever run into. Why such an incredibly limited virtual machine?
>> Even my cell phone came with 256 meg built in two years ago.
>
> Because I don't want to spend too much money on the machine rent, and a
> 48 MB RAM Xen is about all I can get with a budget of 100$ per year.
> Well, there are a few providers which will give me a 128 MB Xen for that
> money, but will the difference in performance be worth the hassle to
> switch providers? My current provider gives me almost perfect
> relaliability for that 100$ and I don't know how the providers which
> give more RAM for the same money perform, maybe they are often down or
> something. And spending more then 100$ yearly on this would be really
> overkill. My thing runs fine, only a bit slow, but reasonable. I just
> want to find out if I could maybe make it better with a little tweaking.
> Can I expect it to work at least three times faster on 128 MB RAM?
> Getting 256 MB would certainly cost too much. Or maybe there are some
> providers which can give me much more performance PostgreSQL server with
> at least several GB of storage for well... not more then 50$ per year.
> (because I must still rent another server to run and SMTP server and few
> other small stuff).
>
> My DB has several tables with like 100000 to 1 million rows each,
> running sorts, joins, updates etc on them several times per hour.
> About 10000 inserts and selects each hour, the whole DB takes 1.5 GB on
> disk now, 500 MB dumped.
>
> If I could shorten the time it takes to run each query by a factor of 3
> that's something worth going for.

Well, my guess is that by running under Xen you're already sacrificing
quite a bit of performance, and running it with only 48 Megs of ram is
making it even worse. But if your budget is $100 a year, I guess
you're probably stuck with such a setup. I would see if you can get a
trial Xen at the other hosts with 128M or more of memory and compare.

In response to

Responses

Browse pgsql-performance by date

  From Date Subject
Next Message Miernik 2008-07-23 23:04:04 Re: how to fix problem then when two queries run at the same time, it takes longer to complete then if run in sequence
Previous Message Miernik 2008-07-23 20:32:03 Re: how to fix problem then when two queries run at the same time, it takes longer to complete then if run in sequence