SSDs and 64K sectors

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Question :

SSDs tend to have a natural 4K sector size as far as I know, but would it be beneficial to format Windows cluster size at 64K? This is good practice for spinning rust, but is it relevant on SSDs?

Answer :

Yes, 64KB is still the current recommendation as it has to do with partition alignment. To quote Jimmy May from the the SQL CAT team:

Partition alignment remains a best practice for all versions of
Windows Server as well as SQL Server, including SQL Server 2012 & SQL
Server 2014. No exceptions. Period.

As part of the Best Practice guide referenced in that article, the following line is quite explicit:

The file allocation unit size (cluster size) recommended for SQL
Server is 64 KB

As for a SSD vendor’s perspective, I point you to Argenis Fernandez‘s blog post about this very topic. Pure even recommends 64KB for NTFS block size, so I think it’s safe to assume this is a pretty universal truth.

Just came across this 2-year old link:

It implies that 64K NTFS cluster size is still recommended for SSDs

To improve this answer it would be ideal to hear from real-life experience with latest generation SSDs (FusionIO or SATA-controlled). Maybe 256K is even better for columnstores on SSDs!

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