Note that this is based on what we (my readers and I) have witnessed in our labs and results my vary depending on the firmware and driver used. The following table shows the Vendor, Controller and Queue Depth.
The value listed under AQLEN is the queue depth of the storage adapter. Run the esxtop command on the ESXi shell / SSH session. If you want to contribute, please take the following steps and report the Vendor, Controller type and aqlength in a comment please. mpt2sas_ raid_queue_depth: int Max RAID Device Queue Depth (default= 128) mpt2sas_ sata_queue_depth: int Max SATA Device Queue Depth (default= 32) mpt2sas_ sas_queue_depth: int Max SAS Device Queue Depth (default= 254) Erik Bussink was kind enough to provide me with these details of one of the controllers he is using as an example, first in the list is “RAID” device – second is SATA and third SAS… As you can see SAS is the clear winner here, and that includes NL-SAS drives. Although typically the price difference between SATA and NL-SAS is neglectable, the queue depth difference is not. Some controllers take: SAS / NL-SAS and SATA. So I figured I would make this thread a source for that info.īefore we dive in to that, I want to show something which is also important to realize. I have not been able to find a good source for this. I guess the only info missing is queue depth of the controller. According to the VSAN HCL also provides “Virtual SAN Pass-Through”. According to the website above it is based on the LSI 2008 and provides the following feature set: 2×4 port internal SAS, no cache, no BBU, RAID 0, 1 and 10. Just as an example, the Dell H200 Integrated disk controller is on the VSAN HCL. 
I figured I would share the link with you, as it will help you (especially consultants) when you need to go through this exercise multiple times: I have found myself digging through documentation and doing searches on the internet until I stumbled across the following website. ** NOTE: This post is not about VSAN disk controllers, but rather about disk controllers and their queue depth. 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.
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? (Local disks, not FC based…) 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.
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