Good post by Duncan Epping (thank you)
I have been working on various VSAN configurations and a question that always comes up is what are my disk controller features and queue depth for controller X? Note that this is not only useful to know when using VSAN, but also when you are planning on doing host local caching with solutions like PernixData FVP or SanDisk FlashSoft for instance. The controller used can impact the performance, and a really low queue depth will result in a lower performance, it is as simple as that.
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