Intel X25-M Raid 0 Performance issues

[cirdecus]

Hello,

I'm using an Intel 8 port PCI-E SAS/SATA controller in an ASUS Rampage III Gene motherboard with 8x Intel X25-M 80GB SSD Harddrives.

for some reason, the scaling in my sandra benchmarks is horrible. I'm getting about 600MB/s read speed while I'm seeing similar benchmarks of 2 and 4 of these drives actually doing more..

Is there something i'm doing wrong here? Is there really no different in 8 drives as opposed to 4?

 

[saint19]

AHCI? and NOT TRIM support on RAID 0, so, the performance is a little less that you wait.

 

[cirdecus]

the set-up is overkill and incorrect...

Given that i haven't mentioned the application, your comment is probably a bit premature. Overkill as it may seem, I just can't seem to figure out why the performance isn't scaling.

If any of you have seen the samsung SSD video of 24 raid 0 SSD's, you'll see that performance get skyrocket to 2,000MB/s or more. Thats what I have been aiming for. The Intel PCI-E controller should be able to handle it.

I'm thinking that there's some settings that can be tweaked to get more performance scaling out of the drives in the Raid 0, maybe TRIM or some other things. If you notice on the world sandra benchmarks, these intel drives are scaling much better than what I've seen so far.

Anyone who has some experience in large SSD raids who can help would be greatly appreciated!

saint19 may be on to something. Is there some type of firmware flash that can be done to enable TRIM in AHCI?

 

[cirdecus]

After talking with an Intel rep, it seems that the 4x lane that the controller uses is probably maxed out. While I'm seeing 3 drives do 720MB/s my 8 cannot do more than 660MB/s.

Can any of you confirm this possibility and possibly offer me suggestions for an alternative controller?

 

[cjl]

That seems entirely possible. You're trying to get an incredible amount of bandwidth there, so you'll need a controller with an interface that can handle it. If that's the case, you should look for a controller with a PCI-E x8 or even x16 interface.

 

[DoomsWord89]

8x 80GB SSD's makes my wallet and head hurt.

 

[cirdecus]

Yep, the x4 lane is the culprit here. I'm hitting the ceiling of the PCI-E lane. There are a few x16 PCI cards out there that i'm going to try and get my hands on. They should raise the limit to around 8,000MB/s which is plenty. These drives should reach 2,000MB/s once full configured.

As far as bigger being faster, I'm not so sure thats always the case. Raid has been tremendously consistent with SSD's and 8 drives will most certainly destroy any single drive setup

Anyway, looking forward to getting this project completed and opening up some serious bandwidth. Thanks guys!

 

[wolfram23]

Unfortuantely you'll never get TRIM support so it won't be too long until the RAID starts to slow down... TRIM can only be supported on single ACHI drives, or single drivers in RAID set up (ie: you might have HDD in RAID but a single SSD) and in that case you have to download the RST drivers from Intel (Rapid Storage Technology). I'm not exactly sure how a RAID controller would change things, or if it would at all, but AFAIK the way RAID0 works basically means it's impossible for TRIM to work. So I hear.

 

[DoomsWord89]

Unfortuantely you'll never get TRIM support so it won't be too long until the RAID starts to slow down... TRIM can only be supported on single ACHI drives, or single drivers in RAID set up (ie: you might have HDD in RAID but a single SSD) and in that case you have to download the RST drivers from Intel (Rapid Storage Technology). I'm not exactly sure how a RAID controller would change things, or if it would at all, but AFAIK the way RAID0 works basically means it's impossible for TRIM to work. So I hear.

Exactly
Two SSDs in RAID is trouble enough.