What should the I/O size be set to in a VMware VDI solution utilizing VAAI...

In a VMware VDI solution utilizing VAAI XCOPY on XtremIO, the I/O size should be set to 256 kB.This setting is recommended to optimize the performance of the storage array during XCOPY operations, which are used to offload the copying of data within the storage array to the array itself, freeing up host resources1.

References:

The Dell support knowledge base article on using a VAAI claim rule to set the XCOPY size when using XtremIO for ESXi hosts recommends setting the XCOPY system value to 256 kB for XtremIO arrays1.

Additional information on VAAI XCOPY and its configuration can be found in the “Introduction to XtremIO X2 Storage Array” document, which provides insights into the system features that support such operations2.

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