Inspired by the recent StoragMI video our gracious leader posted: https://youtu.be/wbl2dYgjMQ4 I wanted to try something similar.
I have two 120GB SSD’s and two 6TB HDD’s.
I don’t get it, performance of my tiered storage space on Server 2016 is worse than the HDDs’ in raid1. Like much worse, sequential writes in raid 1 are 230 where as with the tiered storage space, I’m getting erratic speeds from zero to 34, then jumping to 100 and back down to zero. Weirdly, when I run a crystal disk speed test and it works pretty well. But as soon as I begin a large file copy (robocopy my files back over from an older single disk) it sux and speeds drop lower than the software HDD mirror.
Any help or suggestions would be appreciated. At the end of the day, its a NAS and the HDD’s are fast enough for the network, but it’s really annoying me I can’t seem to get it to work. Plus I want to use those SSD’s.
Here are my PS commands after I get the drives installed:
New-StorageTier -StoragePoolFriendlyName “Mirror Pond” -FriendlyName SSD_Tier -MediaType SSD -ResiliencySettingName Mirror -NumberOfColumns 1 -FaultDomainAwareness PhysicalDisk
New-StorageTier -StoragePoolFriendlyName “Mirror Pond” -FriendlyName HDD_Tier -MediaType HDD -ResiliencySettingName Mirror -NumberOfColumns 1 -FaultDomainAwareness PhysicalDisk
$ssd_tier = Get-StorageTier -FriendlyName SSD_Tier
$hdd_tier = Get-StorageTier -FriendlyName HDD_Tier
New-VirtualDisk -StoragePoolFriendlyName “Mirror Pond” -FriendlyName Vault -StorageTiers @($ssd_tier, $hdd_tier) -StorageTierSizes @(22GB, 5588GB) -ResiliencySettingName Mirror -WriteCacheSize 95GB
Set-StoragePool -FriendlyName “Mirror Pond” -IsPowerProtected $True
Then I format the Virtual disk to ReFS and restart
Microsoft:
https://docs.microsoft.com/en-us/windows-server/storage/storage-spaces/understand-the-cache
Tuning: