Обсуждение: 9.1 vs 8.4 performance

On Fri, Sep 21, 2012 at 7:32 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
> Hello,
>
> I have two postgresql servers 9.1.5 and 8.4.8  running on ubuntu machine,
> both are fresh installs and both has the same configuration files and
> databases.
>
> I am running queries sequentially on each machine using a database  dumped
> from a life server ,  and 9.1 server is much slower than 8.4.
>
> I am wondering what might be the cause for this behaviour?  Does 9.1
> requires more attention on setting some parameters ..  ?

At this level of detail, it is impossible to give an answer.  Some
people will find 9.1 faster, some slower.  I suspect more will find it
faster than slower.

Can you provide an easily reproducible test case?

Cheers,

Jeff

On Fri, Sep 21, 2012 at 8:32 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
> Hello,
>
> I have two postgresql servers 9.1.5 and 8.4.8  running on ubuntu machine,
> both are fresh installs and both has the same configuration files and
> databases.
>
> I am running queries sequentially on each machine using a database  dumped
> from a life server ,  and 9.1 server is much slower than 8.4.

So how different or similar are these two machines?

If its not too much work, swap them around and retest to see if its really the DB/version or the machine.

-----Original Message-----
From: pgsql-general-owner@postgresql.org [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Scott Marlowe
Sent: Friday, September 21, 2012 3:01 PM
To: salah jubeh
Cc: pgsql
Subject: Re: [GENERAL] 9.1 vs 8.4 performance

On Fri, Sep 21, 2012 at 8:32 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
> Hello,
>
> I have two postgresql servers 9.1.5 and 8.4.8  running on ubuntu
> machine, both are fresh installs and both has the same configuration
> files and databases.
>
> I am running queries sequentially on each machine using a database
> dumped from a life server ,  and 9.1 server is much slower than 8.4.

So how different or similar are these two machines?


--
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One thing I sometimes forget to do after loading up an empty DB with data is to run "analyze".  I usually "remember"
onceI see poor query performance, run the analyze, and its fixed. 

-----Original Message-----
From: pgsql-general-owner@postgresql.org [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Scott Marlowe
Sent: Friday, September 21, 2012 3:01 PM
To: salah jubeh
Cc: pgsql
Subject: Re: [GENERAL] 9.1 vs 8.4 performance

On Fri, Sep 21, 2012 at 8:32 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
> Hello,
>
> I have two postgresql servers 9.1.5 and 8.4.8  running on ubuntu
> machine, both are fresh installs and both has the same configuration
> files and databases.
>
> I am running queries sequentially on each machine using a database
> dumped from a life server ,  and 9.1 server is much slower than 8.4.

So how different or similar are these two machines?


--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general

On 09/21/2012 10:32 PM, salah jubeh wrote:

> I am running queries sequentially on each machine using a database
> dumped from a life server ,  and 9.1 server is much slower than 8.4.

https://wiki.postgresql.org/wiki/Slow_Query_Questions

More detail needed.

--
Craig Ringer

On Mon, Sep 24, 2012 at 5:47 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
> Hello Guys,
>
> Thanks for reply, and sorry for late response. Here is more details.
>
> 1. Both servers  are installed on parallel on the same machine, so there is
> no difference in Hardware.
> 2. Both servers have the same configuration setting except the ports (5432
> and 5433).
> 3. I have run VACUUM ANALYSE  command on both databases  and no change in
> performance for both of them.
> 4. The execution plans are certainly different, I tried to use diff and the
> graphical representation pg-admin but the execution plan is a around 1700
> lines, this is why I did not post them.
>
> I have noticed that,  the filter location varies whe run the same queries
> using the two servers. In 8.4 the execution plan is mostly filter then join.
> In 9.1 join and then filter. But this is just a rough overview.
>
> Regards
>
>
>
> ________________________________
> From: "Gauthier, Dave" <dave.gauthier@intel.com>
> To: Scott Marlowe <scott.marlowe@gmail.com>; salah jubeh <s_jubeh@yahoo.com>
> Cc: pgsql <pgsql-general@postgresql.org>
> Sent: Friday, September 21, 2012 9:40 PM
>
> Subject: Re: [GENERAL] 9.1 vs 8.4 performance
>
> One thing I sometimes forget to do after loading up an empty DB with data is
> to run "analyze".  I usually "remember" once I see poor query performance,
> run the analyze, and its fixed.
>
> -----Original Message-----
> From: pgsql-general-owner@postgresql.org
> [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Scott Marlowe
> Sent: Friday, September 21, 2012 3:01 PM
> To: salah jubeh
> Cc: pgsql
> Subject: Re: [GENERAL] 9.1 vs 8.4 performance
>
> On Fri, Sep 21, 2012 at 8:32 AM, salah jubeh <s_jubeh@yahoo.com> wrote:
>> Hello,
>>
>> I have two postgresql servers 9.1.5 and 8.4.8  running on ubuntu
>> machine, both are fresh installs and both has the same configuration
>> files and databases.
>>
>> I am running queries sequentially on each machine using a database
>> dumped from a life server ,  and 9.1 server is much slower than 8.4.
>
> So how different or similar are these two machines?

We need to see the plans.

merlin