Re: Strange Oracle behavior between different environments
From: joel garry <joel-garry_at_home.com>
Date: Fri, 19 Aug 2011 08:59:50 -0700 (PDT)
Message-ID: <c18e856f-2498-4444-b409-96070e96f647_at_c8g2000prn.googlegroups.com>
On Aug 19, 8:00 am, Alex L <ala..._at_gmail.com> wrote:
> We have a 10g database on Solaris 10 that is having some serious
> performance issues. The same database restored onto a Windows machine
> performs fine.
>
> I'm not sure if the Solaris/Windows thing makes a difference at all,
> but I'm curious if anyone knows of anything.
>
> Some background: We discovered the issue while optimizing a query,
> and examining the explain plan cost of the query. Unoptimized, this
> query had a cost of 256000 in 10g/Solaris. It had a cost of 6 in 10g/
> Windows.
>
> Optimized, the query had a cost of 51 in 10g/Solaris, and a cost of 4
> in 10g/Windows. So we're still seeing a pretty huge difference on
> this query alone, and the general performance of the Solaris DB is
> just very poor, despite the hardware being far superior to the Windows
> machine.
>
> The Solaris DB is WE8ISO8859P1 character set. The Windows DB is
> WE8MSWIN1252. Any ideas? Other information I can provide?
>
> Thanks,
> Alex
Date: Fri, 19 Aug 2011 08:59:50 -0700 (PDT)
Message-ID: <c18e856f-2498-4444-b409-96070e96f647_at_c8g2000prn.googlegroups.com>
On Aug 19, 8:00 am, Alex L <ala..._at_gmail.com> wrote:
> We have a 10g database on Solaris 10 that is having some serious
> performance issues. The same database restored onto a Windows machine
> performs fine.
>
> I'm not sure if the Solaris/Windows thing makes a difference at all,
> but I'm curious if anyone knows of anything.
>
> Some background: We discovered the issue while optimizing a query,
> and examining the explain plan cost of the query. Unoptimized, this
> query had a cost of 256000 in 10g/Solaris. It had a cost of 6 in 10g/
> Windows.
>
> Optimized, the query had a cost of 51 in 10g/Solaris, and a cost of 4
> in 10g/Windows. So we're still seeing a pretty huge difference on
> this query alone, and the general performance of the Solaris DB is
> just very poor, despite the hardware being far superior to the Windows
> machine.
>
> The Solaris DB is WE8ISO8859P1 character set. The Windows DB is
> WE8MSWIN1252. Any ideas? Other information I can provide?
>
> Thanks,
> Alex
Show us the plans like the example on http://blogs.oracle.com/optimizer/entry/how_do_i_know_if
Randolf's guide to posting is useful:
http://oracle-randolf.blogspot.com/2009/02/basic-sql-statement-performance.html
Also let us know exactly how you "restored" to the windows machine. Some operations can reorganize data, changing blevels and such. Exact patch levels, system statistics, various statistics gathering methods can influence information available to the optimizer and how it behaves.
jg
-- _at_home.com is bogus. It's not a gang, it's a club. http://www.signonsandiego.com/news/2011/aug/18/60-arrested-el-cajon-chaldean-organized-crime-case/Received on Fri Aug 19 2011 - 10:59:50 CDT