I hope you can help me with this storage performance issue I'm dealing with.
ESXi 6.7 fully patched.
2 x 4gb hard drives, same brand, model and firmware version, both formatted in VMFS6.
I'm running Ubuntu server 22.04.1, with its root partition on disk 1, media archive partition on disk 2.
The root partition performance as measured with hdparm is around 59 MB/sec, the partition on disk 2 is 170 MB/sec and I can't figure out why there is such a difference between the two.
Both partitions are thick provisioned, all other guests are shutdown and the linux server is sitting idle.
What I tried:
I swapped the SATA cables, no change.
I moved the slow drive to another SATA port, no change.
I checked the interface for both disks, both are running on SATA III mode.
I checked S.M.A.R.T. data for anything unusual, no apparent issues.
I set up another linux system running xubuntu, same issue.
Then I did a test using dd from the hypervisor console, and it seems the performance of both disks is similar. Not sure if caching might be masking the issue here.
Not sure what else to try... thank you for your help.
hhmmm, interesting question