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Dell PowerEdge 630 with H730 PERC SSD and TRIM Support
Hi there.....
I'm building a PowerEdge 630 Server, which has mostly SSD drives installed. In order to get the best performance from the disks overtime, I was looking at TRIM support with hardware RAID. Using the PERC H730 controller, I hardware raided the first 2 SSDs as RAID 1 (which I might rebuild later as SW raid). I then started to look at the other SSD disks, which I need to be individual disks.
The options I have are to create each disk as a Virtual RAID 0 and present that to the OS using the H730 or I can set the disks to non-RAID and pass them through to the OS directly.
What I'm unsure about here is the best way to do this considering the SSD's, TRIM support and overall performance? Do I even need to consider TRIM support? The documentation is unclear on the controllers ability to support it in hardware RAID mode, but firmware documentation does say non-raid disks only.
I have run some tests to try and figure this out, but it's still a work in progress.
With both a virtual HW raid0 disk and a non-raid disk, with ext4 filesystem. I have filled disk space up so both devices are full. Using the command #dd if=/dev/zero of=/diskX/zeros ***=1M
I then delete the file and watch how long before the OS shows the disk as having free space. It some instances the Virtual raid disk has been better. I have also been running some speed tests on the disks.
Mount options for the non-raid disk include “discard” and I have also used the #fstrim /diskX, command.
Unsure which is the best way to go here any ideas?
DELL-Daniel My
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January 23rd, 2016 13:00
Hello
If you are going to run software RAID then you should put the drives in pass-through mode. You should not run RAID on top of RAID. If you are not going to use software RAID then you will get better performance putting the drives in RAID 0s. The controller will not use write cache for drives in pass-through mode, so you should get better performance with single drive RAID 0s rather than pass-through.
I would only recommend pass-through mode if you are running a configuration that needs it like software RAID.
Thanks
RSBIGRED
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January 25th, 2016 01:00
Thanks for the reply. My question did not suggest running hardware raid with software raid on top. It's one or the other I'm aware of that. My question is really about drive performance and TRIM support when using this server and its raid card for a individual drive, or using the dives natively. Does the hardware RAID 0 attached to a single disk, give better performance vs a single non-raid disk (passed through the same controller as non-raid) regarding TRIM support? What method provides the best performance?