Recommended Stripe Size

[shepcon]

I'm in the process of creating a new RAID volume that will be used specifically as a Veeam B&R 9.5 4a repository for my VMware 6.7 environment. Dell PE R740 and currently only 3 VMs with likely little future growth to maybe 5 VMs. I have read a good bit about storage and performance and I'll be formatting the new volume with ReFS and 64K. My question is regarding the stripe size during the RAID build. Dell Perc H740P does allow me to define the stripe size. I have read in Veeam KBs to use 128k or 256k stripe size for backup repositories. My question is which should I pick (128k or 256K)? Dell doesn't allow me to pick the block size during the RAID build, so it will be 512 bytes.

Thanks for any input.
Ken

[Andreas Neufert]

As a general rule of thumb please check https://bp.veeam.expert/repository_serv ... y_planning
depending on vendor controller and caches other settings could be faster. If you do not want to test go with the documented ones from the link.

[shepcon]

Thanks, Andreas. I have already read that KB and it does have a lot of helpful information. The part I'm confused by is Veeam's recommendation of 128k or 256k for stripe size. I understand the importance of testing but I must start with a choice 1st. And if anyone has done similar testing using similar Dell hardware, I'd like to reduce the number of steps to the testing process.

"Tip: As can be seen from the field, optimal value for the stripe size is often between 128 KB and 256 KB; however. It is highly recommended to test this prior to deployment whenever possible."

Ken

[Gostev]

As a rule of thumb, you should go with 256KB. This is usually a safe choice, and we don't recommend going above this value. Note however that this is for the default Veeam block size. If for whatever reason you plan on using non-default block sizes in Veeam, you will need to adjust stripe size accordingly.

In any case, I doubt you will find anyone here who bothered to do proper performance testing with different stripe sizes on your particular RAID controller. Contrary to that, very few people even know to change the default stripe size to better match Veeam workload

[gummett]

Just sharing the updated link to the relevant best practices page, to save others the effort
https://bp.veeam.com/vbr/VBP/3_Build_st ... block.html