Different VMFS Block Size difference on storage array

[dee0606]

We could see there is difference of block on the storage array like 8K and 64K on vmfs using storage array. Anyone have try to modify the block size 1 MB default irrespective of  small files and large file?

Reason for modification block size because smaller and larger block size unable to calculate the IOPS available within underlying storage array. Better the block size controller will have better visibility on the IOPS available on the storage system.

 

[Duncan Epping]

the block size of VMFS doesn't dictate the block size you see at a storage level. the blocksize for VMFS is mainly used as a unit of allocation, and not as much as a unit of IO. Within that block you could see a variety of blocksizes. It ultimately is defined by what your App/Guest OS is doing.

[dee0606]

Thanks  for response. 

To make uniform and get extact IOPS. Keeping all similar Block Size VM on one datastore. Do we feasibility to check the vmdk block size from esxi point. 

[Duncan Epping]

Like I said, the blocksize of the volume doesn't make a difference in terms of the blocksize you will see on the array. if your guest of app is doing 8k blocks, or 32k blocks then that is what the array will see. So if you see a variety of blocksizes, which is highly likely, then this is because the applications and guest operating systems are producing those different sizes.