SQL server high cpu usage

[CheckMeNot]

I have a Windows 2003 Sever with 8 GB RAM running SQL server 2005 SP1. Out of the total memory, SQL is dedicated 6GB memory and 2GB is for the Operating System. Well since a last few days, i have noticed that some server started consuming more CPU then it should consume normally. I tried running many memory and processor related tests but nothing gave me any hint what is causing this steep rise of processor utilization. We had a planned downtime so i restarted the server and everything was fine then. I still don't understand what was actuallu wrong and what was causing it. I have a feeling that this rise in cpu utilization will be back again in a month or so... I'm not sure but i feel so. Can this be an issue due to continuous uptime of the server? We can have a downtime only once in three months... Help!

[Raine]

There may be above 20 reasons for the same, but try this : Set max server memory and that should vanish. If it does, that means it was caused by some server which is not too active but is consuming memory and CPU usage. Also did you reindex any tables? How often do you run such tasks? including update statistics. What is the system type x64 or x86?

[CheckMeNot]

It is a x86 based system. We run a weekly reindex and a daily update statistics. for now i have set the max memory to 6144MB. Let see if it has some effect or does it come back. Will get back to you if there is any such problems in future. Thanks for the help..!

[Eric B]

There are some problem of 'Lazy Writers' on SQL. If you this you have this problem which is causing the cpu peak then you should update your SQL to SP2 and there are some update patches that must be applied after you update your SQL to SP2. But make sure that this is the problem and only then apply the fixes. This may also screw your configuration.