Comments on: SQL Server on a SAN: Dedicated or Shared Drives?

By: donaldc

donaldc — Wed, 16 Nov 2011 13:18:18 +0000

Thank you – that does indeed help and is what we plan to do. Apologies for the earlier shameless flattery, but it was well meant!

By: Brent Ozar

Brent Ozar — Wed, 16 Nov 2011 13:12:43 +0000

DonaldC – thanks, glad you liked the post! For configuration, I recommend following Ronald Reagan’s SAN configuration tip: “Trust, but verify.” Test it with different allocation sizes and your own load patterns, and find what works best for you. There’s no one universal guideline that works for everyone all the time. Hope that helps!

By: donaldc

donaldc — Wed, 16 Nov 2011 13:07:25 +0000

Apologies for coming very late to the party on this (as always) excellent post, but we are just in the process of migrating from an HP EVA to a NetApp FAS3240. I remember pretty much following the Microsoft rule book for partition alignment and allocation unit size when I wrote our company configuration standards for SQL Server on HP arrays. I notice that NetApp guidelines suggest there is no discernible advantage in using 64KB over 4KB allocation units. I can understand that this makes sense because the underlying WAFL file system operates with 4KB blocks, but just wondered how you normally recommend configuring NetApp arrays?

We are going to be running baseline tests with different allocation sizes and will be happy to share the results.

Many thanks for another scintillating blog series.

donaldc

By: Miguel Angel Sanchez

Miguel Angel Sanchez — Tue, 08 Nov 2011 20:09:24 +0000

Thank you very much as always you rock.

Another quick question what could be considered as normal for PLE counter and for Compilations, I can see in my system around 148 compilations

Thank you