Hi,
I've problem with datastore speed in ESXi 5.1. There are two datastores based on local SATA drives. Both drives are the same models - WD1002FAEX 1TB SATA III 64MB.
I've testes both of them and the first one is avg 110MB/s fast, second is avg 80MB/s fast.
Only difference between the datastores is VMFS version, first (faster) is 5.54 (created before upgrading from ESXi 5.0 to 5.1, second is VMFS 5.58 (created after upgrading to 5.1).
Test was made on the same VM (migrated between this two datastores).
Changed cables, changed ports (SATA III, SATA II - no difference).
I suspected drive issue and checked it under different OS (WindowsXP with several disk speed measurement tools) - result was OK, normal speeds.
Only difference is VMFS version, newer = about 30MB/s slower. Is that possible?
Is there any possibility to downgrade (recreate) VMFS to 5.54 instead 5.58?
P.S. Sorry about my english.