Hi Andy,

Thanks for your response and sorry its taken so long for me to reply - been on holiday with no access to technology...it was magic. 🙂

With regards to the Tiered Storage, there's an algorithm within the SAN Management System that runs every night and promotes/demotes blocks based on usage patterns, plus some 'pinning' that the SAN Admins do for particular blocks they manually tune. Whilst it is good in most cases, there are times when blocks get promoted/demoted too late/early which can affect performance. But in the grand scheme of things, this is not so important in our case.

As to talking to the SAN Guru, this is where the problem lies...the SAN Admins just administer and are not really into the why's-and-wherefore's of performance with the SAN environment. This is why I came here to try and reach out to some gurus in the hope of getting opinions to the help my understanding of how we should be looking to setting up these environments, which are so different to the DAS setups and the 'old' SAN environments - and politics mean I cannot get an outsider SAN specialist in to help with this.

One thing I was looking at was how the paths to each of the Volumes (ie, the LUNs, as we map one LUN to each Windows Volume), from the HBAs through the SAN Switch, and into the Storage area can affect things. So, for instance, is it better, performance-wise, to have, say, mdf/ndf files on separate LUNs to the ldf files, because they route through different paths to the Storage? I'm trying to understand if these sorts of things matter, and it's difficult to test myself as I don't have sole access to a SAN environment to test myself. :crazy:

Hopefully, some SAN Guru will come across this thread and point me in the right direction. 😀