Solved

LATCH_EX with CXPACKET causing query performance degradation

Posted on 2009-05-13
1
1,948 Views
Last Modified: 2012-06-27
SQL Server 2000 SP4 Build 2187. When runing simple SELECT query with INNER joins causing LATCH_EX waittype with huge number of CXPACKET causing consistent high CPU with performance degradation. Indexes are in place with stats updated. Moving data files to different disk didn't make any difference. Execution plans are changing with and without 'TOP' clause. With 'TOP' clause plans are generating with 'INDEX SEEK, Nested Loop' while without 'TOP' clause changing to 'INDEX SCAN, Table Spool, Hash Match, Merge Join'. WHY? Can anyone give some action plan?
0
Comment
Question by:info2rafiq
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
1 Comment
 
LVL 51

Accepted Solution

by:
Mark Wills earned 500 total points
ID: 24381764
Hi info2rafig,  

sounds like some I/O problems maybe...

Are you running profiler by chance ? http://support.microsoft.com/kb/929728

There is a fairly high level overview of wait types and what to look for : http://www.sqldev.net/misc/waittypes.htm

A fella by the name of Thomas Davidson is the guru on 2000 performance. There is a whitepaper floating around, but his presentation is a bit more graphic : http://www.sqldev.net/events.htm#SQL_Connections_12-15_October_2003,_Palm_Springs_CA_  look for the one in the middle : SPR-201-4

Apologies about all the links, but performance is a minefield potentially, and best to understand what might be causing it first. So, have a look and read, and then come back with some more questions if needed - OK ?
0

Featured Post

Get 15 Days FREE Full-Featured Trial

Benefit from a mission critical IT monitoring with Monitis Premium or get it FREE for your entry level monitoring needs.
-Over 200,000 users
-More than 300,000 websites monitored
-Used in 197 countries
-Recommended by 98% of users

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Load balancing is the method of dividing the total amount of work performed by one computer between two or more computers. Its aim is to get more work done in the same amount of time, ensuring that all the users get served faster.
I have a large data set and a SSIS package. How can I load this file in multi threading?
This video shows, step by step, how to configure Oracle Heterogeneous Services via the Generic Gateway Agent in order to make a connection from an Oracle session and access a remote SQL Server database table.
Via a live example, show how to shrink a transaction log file down to a reasonable size.

627 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question