May 4, 2011 at 11:42 pm
Hi all,
We are facing some issue!!
There is an application which was running on the MS SQL 2000 server. The performance of that was up to the mark. Now, we had to migrate the application to SQL Server 2008. I see a considrable degradation in performance. Is there any reason for the same? Do we have to change anything or any settings in 2008 for it to increase the performance??
PS: The hardware in both the servers is almost identical and we can even presume that the 2008 server hardware is a bit better too!
Pramod
May 4, 2011 at 11:45 pm
Have you rebuilt all indexes and updated all statistics since the upgrade?
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
May 5, 2011 at 3:34 am
Yes. We have rebuit the indexes and updated the statistics.
Pramod
May 5, 2011 at 5:35 am
It's possible you've hit a regression, a piece of code that worked well in 2000 but not so well in 2008. Usually this happens on code that is problematic to begin with, but squeeked by on 2000. To actually be able to help I'd need to see the code & structures involved along with an execution plan.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 5, 2011 at 6:49 am
That means that a code that worked well in 2000 can go haywire in 2008. What makes it happen so?? is it the engine? so, it is not some sort of settings change or something like that!
We have to go thru this painful process of finding the bad code which is causing this then!! There are many pages in the app which have become slow. That means that we have to run the app thru profiler and find the part of the code which is actually taking longer and then tune it rt?
Thanks for replies anyways...
Pramod
May 5, 2011 at 7:10 am
pramod_yg (5/5/2011)
That means that a code that worked well in 2000 can go haywire in 2008. What makes it happen so?? is it the engine? so, it is not some sort of settings change or something like that!We have to go thru this painful process of finding the bad code which is causing this then!! There are many pages in the app which have become slow. That means that we have to run the app thru profiler and find the part of the code which is actually taking longer and then tune it rt?
Thanks for replies anyways...
Pramod
Then you already know where to look!
That'll help get you back on you feet in a couple hours / days.
May 5, 2011 at 7:20 am
yes, the problems do occur in the engine, but they're very rare. If you're hitting them all over the place, then I'd suggest one of two things is true. You have one query that is called all over the place and it has a problem, or you have a particular code pattern that you use a lot that is problematic.
It is possible that you're just hitting a setting issue. Did your old server have a different cost threshold for parallelism or something like that? Different defaults on connections? There are lots of things that could cause differences in performance.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 5, 2011 at 7:24 am
How did you migrate the DB?
Are you sure no indexes were missed?
Memory setting correctly configured?
Not perhaps on an inferior IO subsystem?
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
Viewing 8 posts - 1 through 7 (of 7 total)
You must be logged in to reply to this topic. Login to reply