Changed App Server from single to dual processor virtual machine; Now queries take twice as long! Why?

[Deborah_Hack]

OnBase 13 SP2

We have our Application Server on a virtual server. In an attempt to improve performance, we reconfigured the virtual machine from a single processor to dual processor. Instead of improving performance, the opposite has occured. For example, queries now take TWICE as long to return the hit list.

While I'm waiting for help from my support, can anyone give me any ideas of why performance got worse? Any ideas of what I should check?

It's been a bad day.........

Thanks for any suggestions.

-Deborah

[Laurie_Mordick]

Matthew - Thanks for the great information.  One additional point for my understanding, you stated you keep the Application Server at one core, what about the SQL and web servers.  Is that a recommendation or best practice on those VMs also?

We did note a significant degredation in performance this last time we upgraded to OB V12 and moved our SQL Server to Win2012, HyperV.  Our SE team, of course is denying it is related to the VM (we were on a dedicated server prior to upgrade) and so we are living with less than optimal performance.  I'm wondering if # of cores on the SQL and Web (ArchiveLink and BIC integration on these servers also) is having a detrimental effect. 

Thanks so much!  L  🙂

[John_Anderson4]

I think it's recommended to keep your SQL server on a dedicated physical server, not a VM. At least that's always what we've been told (and I think it's reflected in the OnBase documentation as well, somewhere).

[Michael_Brock1]

What was your CPU utilization like before and after the change?Is hyper-threading enabled? Disabling hyper-threading with one vCPU will give you access to one full core. The same as two vCPU with hyper-threading enabled since that is only 2 logical cores. Disabling hyper threading will also help with MS licensing since SQL (depending on version) in a vm is licensed per vCPU, regardless of it being a full core or logical core.http://www.virtualinsanity.com/index.php/2010/07/02/give-me-the-whole-core-and-nothing-but-the-whole-core/You can also look into CPU reservations if the server is delayed in scheduling a core, but there are downsides to this too.http://www.joshodgers.com/2012/07/22/common-mistake-using-cpu-reservations-to-solve-cpu-ready/Michael

[Joe_Pineda]

Also look at Parallellism in SQL

[Laurie_Mordick]

Thank you all for the great information.  I'm going back to my DBA team and having a serious discussion!  L  🙂