Question : Problem: Strange CPU spikes

Hello,

One of our Win 2003 Ent, SQL 2005 servers is behaving strangly.  Every 6th ping seems to take a long time to return.  It corresponds with a spike of activity on one of the processor cores.  the server has 2 NICs - I have updated to the latest drivers, tried using just the first, just the second and both.  We still get the slow ping.  I have attached the screen shot of the pings and the task manager.

How should I start to investigate this please?  I have looked at performance monitor which tells me the same as task manager but I don't know how to pin point the cause.

Cheers
Tom

Answer : Problem: Strange CPU spikes

Can you stop SQL for a moment and recheck ping?  with SQL stopped ping should go back to normal if SQL is the problem - this will avoid driver updates I think.

do something DNS checks too - be surprised how many things need good DNS lookups to work properly - if a SQL job is trying to authenticate or find a remote server it could be causing a problem.

Also look in the event log - any issues around disk drives?  a disk on the way to failing could make many such issues.  if SQL is unable to reliably write a transaction log it's going to cause hell.