Please start any new threads on our new
site at https://forums.sqlteam.com. We've got lots of great SQL Server
experts to answer whatever question you can come up with.
| Author |
Topic |
|
mordzy
Starting Member
2 Posts |
 Posted - 2005-07-20 : 07:10:27
|
| We have a Dual processor SQL 2000 box and another IT person had told us to only tick one CPU and having two ticked reduces performance. Sounds rediculas to me. basicly in 'SQL server properties' click the 'processor' tab, and make sure only one CPU is ticked in the 'Processor Control'Can someone please explain if this is correct or not and why?Thanks guysAlex |
|
|
mr_mist
Grunnio
1870 Posts |
Posted - 2005-07-20 : 07:49:47
|
| What reason has he given to do it?-------Moo. :) |
 |
|
|
mordzy
Starting Member
2 Posts |
Posted - 2005-07-20 : 08:31:53
|
| we run there software on our server.. it runs slow. when asking them why they said and i quote "You have both processors ticked and this slows down SQL" |
|
|
|
Thrasymachus
Constraint Violating Yak Guru
483 Posts |
Posted - 2005-07-20 : 09:11:46
|
| ummmmm sounds like a bunch of crap. is this guy a MS Great Plains partner from NJ by any chance?Hardware is not really my forte but let me give this a go. If I remember correctly, if your execution plans utilize paralellism, I believe SQL will send the the parallel executions through seperate processors to speed up execution. Or something like that. I believe this is true of all multi-threaded apps on multiprocessor machines.Sean RoussyPlease backup all of your databases including master, msdb and model on a regular basis. I am tired of telling people they are screwed. The job you save may be your own.I am available for consulting work. Just email me through the forum. |
|
|
|
robvolk
Most Valuable Yak
15732 Posts |
Posted - 2005-07-20 : 09:31:43
|
| In a highly contentious system, it is possible that enabling both CPUs can cause the server to get bogged down while processing one query. This can be minimized or eliminated by tuning the query, or if the server is getting a lot of traffic, adding more CPUs. However, a blanket statement "enabling both CPUs slows it down" is ridiculous, especially if you have not tested both scenarios. |
|
|
|
stephe40
Posting Yak Master
218 Posts |
Posted - 2005-07-20 : 10:13:54
|
| Yeah, when you look at execution plans it will show if it using both processors. SQL server in many cases only uses one processor because many queries are small enough that the overhead of splitting the work is more then just sending the query to one processor. There is a query threshhold limit where if the optimizer thinks a query will take longer it will then return a dual proc execution plan. So even if you are using both processors the server will only use both if it thinks it will speed things up.- Eric |
|
|
|
|
|
|
Dual CPU in SQL 2000