4 Replies Latest reply on Mar 18, 2015 10:16 AM by thejun

    DPA and processor Affinity

    thejun

      I believe DPA is monitoring all cpu's on the server, even though SQL is only using a subset of the processors.  So the metrics are getting skewed because of this.  Can anyone confirm this and does anyone now if there is a fix?

        • Re: DPA and processor Affinity
          mandevil

          We will monitor two resource metrics.  One is O/S CPU utilization which is all processors available to the host.  The other metric is Instance CPU utilization (processing consumed by SQL Server).  You can choose whichever one makes more sense to focus on.  Is this what you are referring to or am I missing the mark here?

            • Re: DPA and processor Affinity
              thejun

              yes, but since those 2 metrics come out to be exactly the same, the instance metric maybe not working as it should??

                • Re: DPA and processor Affinity
                  mandevil

                  Is this host dedicated to SQL Server?  I agree though, there *should* be some OS overhead, even if minimal.  Do you mind opening a support ticket?  We can share our calculations via a support case which may help determine why they are the same (we can go for the raw data directly from SQL Server).

                    • Re: DPA and processor Affinity
                      thejun

                      Sure I can open up a support ticket.  But its pretty obvious that is is the same.  come to looking at it, all the graphs are skewed because its looking at what all cpus are doing, not what is assigned to sql...

                      and to give you some insight on the cpu, i have 16 cpu's assigned, and 64 cpu's total.  so if the instance cpu utilization only tracks what sql is using, it should be pegged at 90-100% all the time, as i had to run a different tool to get the proper metrics...

                       

                      sql-affinity.PNG