Odds and Ends - Tiering, and Performance Planning

A few articles I wanted to briefly highlight:

• Storagebod posted a brief article on automated storage tiering.  To briefly summarize, imperfect automated storage tiering is better than nothing... it is an easy way to get value out of SSDs in an existing environment and it provides a mechanism to move less-used data off of FC drives and onto SATA drives.  One thing is certain... the importance of manual data layouts is decreasing.  Between array architectures that don't 'allow' it (XIV being the most notorious example), don't 'need' it (NetApp FAS), and traditional architectures getting performance-driven automated storage tiering, using Excel to mismanage storage layouts could finally be over.  Dimitris makes the point that due diligence still needs to be applied to allocations that require high performance a few times a month to ensure the volumes don't get migrated to the wrong tier (among other comments).  There are excellent comments on that post from EMC and NetApp discussing the two approaches.
• Dimitris also has a good post on vendor competition and under-sizing proposals to get the sale.  It is worth reading just for the 'basics' explanation of performance-sizing small arrays - it also has some good information on Compellant's architecture.  My comments regarding this vendor comparison are attached to that post.  As always, prior to storage acquisitions, make sure you understand how the vendor determined their bid's sizing and get guarantees on performance/capacity if you are at all concerned about meeting your requirements.
• Chuck Hollis (EMC) and Marc Farley (3PAR) have excellent posts up on storage caching.