Dell R430 - Disk Performance

[robyholmes]

Hi All,

 

We have a Dell PowerEdge R430 which we use as a Hyper-V host. Recently its been causing problems which I'm thinking are disk performance related. I asked Dell to check the hardware and logs sometime ago and they turned up nothing. So after more problems recently I've taken the server out of action and re-installed the OS to provide a clean test bed. I'm running Windows Server 2016 now.

 

The server specs are these:

2x Intel Xeon E5-2623 V3 3Ghz

64 GB RAM

PERC 730 Mini

3x 1.2TB 10K 2.5 Drives

 

The drives are setup in RAID 5 to provide just over 2TB of storage space. The virtual disk is then split in to 100GB of OS with the rest of VM storage.

 

I've run CrystalDisk Mark on the server both before and after drives.

Before Drivers

 

After Drivers

 

I'm concerned about the 4K Read speeds. These seem very low compared to my other servers and compared to the write speeds. I just want to confirm I'm not going mad so I can go back to Dell with this issue.

[robyholmes]

EDIT: Just completed some more tests on other servers and I'm closer than I thought. So maybe there isn't an issue. Just like someone to confirm these look normal.

[PotNoodleTech]

Your speeds look like what I would expect.

 

4k read and write speeds are usually very much lower on mechanical drives. As you only have three drives you're not getting a big read speed increase from the RAID5 like you would if you had 12 drives in there.

 

One thing to check - is your raid card battery backuped? If so you can enable the read and write caching on the array and that may help speeds a bit. Looking at your write speeds I think you already have write back cache on.

[robyholmes]

Your speeds look like what I would expect.

 

4k read and write speeds are usually very much lower on mechanical drives. As you only have three drives you're not getting a big read speed increase from the RAID5 like you would if you had 12 drives in there.

 

One thing to check - is your raid card battery backuped? If so you can enable the read and write caching on the array and that may help speeds a bit. Looking at your write speeds I think you already have write back cache on.

 

It does seem to be performing better now I've re-installed the OS.

I've checked the controller policy as we do have battery backup on the card.

 

Read Policy: Adaptive Read Ahead

Write Policy: Write Back

 

I've checked these against Dell's guidance and they seem to be the best options for our use as a Hyper-V host.

 

Thanks for checking the numbers.