As far as I know, TRIM does not work with RAID 1 arrays either. RAID is kind of a layer between the physical drives and the OS, so it needs a bit extra work to be supported by TRIM. I guess RAID 1 support will follow later on but RAID 0 is more popular (at least among consumers) so supporting it first makes sense.
Right, the RAID controller did not propagate the TRIM commands, since they were not built into the controller, at least that's how Intel SSD guys explained it. My guess is that if RAID 0 is supported, RAID 1 will be supported as well, because the RAID controller will propagate TRIM.
I think the stipulation might be there because TRIM will work when you have RAID mode enabled for the Intel SATA controller as long as the drive isn't in an actual RAID "array"
Basically IRST will successfully employ TRIM to any single SSD as long as the controller is configured as AHCI or RAID, which is a fairly common voiced concern from newer SSD users as they hear they need AHCI for TRIM to work but do not know that Intel's RAID mode will also work (again, as long as the SSD isn't actually in an array)
Great news. I was looking at adding a second identical SSD to my system for added capacity and in RAID 0 for performance benefits, but the lack of TRIM support was making me wonder if it'd be worth it.
I've still not found a version of RST that doesn't stop this from working on their own chipset. With this installed I can't safely eject SATA drives even when set to Hot Swap in the BIOS. Uninstall and it works fine.
Actually, no. Two identical drives in RAID 0 (striping) will result in a single volume with the capacity of both. Two 120GB SSDs in RAID 0 nets you a single 240GB storage device for your OS to see.
RAID 1, on the other hand, is mirroring. This effectvely halves the capacity of the drives in the set, because half is used to create a redundant copy.
Like Slash3 said, 2 120 drives in Raid-0 gives you 240, which is exactly what I'm doing with 2 G2 120 SSDs. The speeds are great, of course they are about your average current Generation Sata3 SSD. But hey I've had these since they came out.
And Honestly I havent been able to benchmark a loss in performence after useing them for months on end under normal useage (except I demux a blu-ray disk to it, which is about a 40 gig Seq. write. which helps it regain any performence it might have lost)
But for everone wondering what boot times are like, well my Acer laptop with a WD 120gig, 4 gigs of ram, Core I5 @2.4ghz SSD boots faster, In fact it boots faster then any phone ipod,pad, Itouch or anything I've ever seen( about 14 seconds from power button to opened IE). This system boots in about 40 seconds at least, but havent timed it. but opening programes is instant.
Linux has had support for RAID and TRIM for quite some time. The support is also agnostic to the vendor of the SSD. I have two Intel SSDs in RAID-0 and TRIM has been working fine for me.
P.S. Linux also supports encryption and TRIM. It's relatively new, and not fully secure, but it exists.
Linux has supported TRIM with LVM for a couple years, but mdraid support is still in the process of being added, with a set of patches submitted only last month.
LVM and mdraid use different codepaths, so there's been some confusion on this matter. But yes, I have used an LVM-striped setup (which is essentially software RAID0) since late last year, and TRIM is working.
If you're using mdraid, check your dmesg for "discard not supported, disabling". Linux won't throw an error if you ask for TRIM and you can't get it, it'll just disable it.
Would you agree that TRIM cannot be used in the following situations: 1. Server virtualization environment: For instance, we install VMware ESXi on a host, and a couple of virtual servers in it. Since TRIM works on deleted files, and files here are VMware virtual disks, the TRIM doesn't help when guest OS deletes files, until the whole virtual disk is deleted.
2. SSD in a Database Server: Again the same, the data in databases is deleted, but the DB datafiles rarely. As long as no file is deleted, TRIM doesn't fire.
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Mugur - Monday, November 21, 2011 - link
Maybe I'm just ignorant, but I don't remember reading that there is TRIM support for RAID 1 either... :-)Phylyp - Monday, November 21, 2011 - link
Agreed - I was always under the impression that having a RAID setup meant forgoing TRIM support. Kristian, could you clarify, please?Kristian Vättö - Monday, November 21, 2011 - link
As far as I know, TRIM does not work with RAID 1 arrays either. RAID is kind of a layer between the physical drives and the OS, so it needs a bit extra work to be supported by TRIM. I guess RAID 1 support will follow later on but RAID 0 is more popular (at least among consumers) so supporting it first makes sense.RMSe17 - Monday, November 21, 2011 - link
Right, the RAID controller did not propagate the TRIM commands, since they were not built into the controller, at least that's how Intel SSD guys explained it. My guess is that if RAID 0 is supported, RAID 1 will be supported as well, because the RAID controller will propagate TRIM.Kristian Vättö - Monday, November 21, 2011 - link
Intel's release notes mention only RAID 0 (it's the Intel link at the end of the article).bunnyfubbles - Monday, November 21, 2011 - link
I think the stipulation might be there because TRIM will work when you have RAID mode enabled for the Intel SATA controller as long as the drive isn't in an actual RAID "array"Basically IRST will successfully employ TRIM to any single SSD as long as the controller is configured as AHCI or RAID, which is a fairly common voiced concern from newer SSD users as they hear they need AHCI for TRIM to work but do not know that Intel's RAID mode will also work (again, as long as the SSD isn't actually in an array)
kyuu - Monday, November 21, 2011 - link
Great news. I was looking at adding a second identical SSD to my system for added capacity and in RAID 0 for performance benefits, but the lack of TRIM support was making me wonder if it'd be worth it.probedb - Monday, November 21, 2011 - link
I've still not found a version of RST that doesn't stop this from working on their own chipset. With this installed I can't safely eject SATA drives even when set to Hot Swap in the BIOS. Uninstall and it works fine.QQuxa - Monday, November 21, 2011 - link
how would raid-0 help with capacity premium? two smaller drives in raid-0 will do nothing for capacity..Slash3 - Monday, November 21, 2011 - link
Actually, no. Two identical drives in RAID 0 (striping) will result in a single volume with the capacity of both. Two 120GB SSDs in RAID 0 nets you a single 240GB storage device for your OS to see.RAID 1, on the other hand, is mirroring. This effectvely halves the capacity of the drives in the set, because half is used to create a redundant copy.
QQuxa - Monday, November 21, 2011 - link
you're right, sorry, i've mixed up :)SlyNine - Monday, November 21, 2011 - link
Like Slash3 said, 2 120 drives in Raid-0 gives you 240, which is exactly what I'm doing with 2 G2 120 SSDs. The speeds are great, of course they are about your average current Generation Sata3 SSD. But hey I've had these since they came out.And Honestly I havent been able to benchmark a loss in performence after useing them for months on end under normal useage (except I demux a blu-ray disk to it, which is about a 40 gig Seq. write. which helps it regain any performence it might have lost)
But for everone wondering what boot times are like, well my Acer laptop with a WD 120gig, 4 gigs of ram, Core I5 @2.4ghz SSD boots faster, In fact it boots faster then any phone ipod,pad, Itouch or anything I've ever seen( about 14 seconds from power button to opened IE). This system boots in about 40 seconds at least, but havent timed it. but opening programes is instant.
SlyNine - Monday, November 21, 2011 - link
Just to clairify. The Acer has a WD 120Gig SSD. not a regular HD and that boot time is counting logging in, and from a full shutdown.Samoht - Monday, November 21, 2011 - link
"Here is a quick brief on what TRIM is and what does it do."Kristian Vättö - Monday, November 21, 2011 - link
What is wrong with it?futrtrubl - Monday, November 21, 2011 - link
"what it does" is correct. "what does it do" is a question.Kristian Vättö - Monday, November 21, 2011 - link
Thanks, fixed. I had Jarred read it through for grammar errors but maybe he missed it.JarredWalton - Monday, November 21, 2011 - link
It was late at night. LOLSunrise089 - Monday, November 21, 2011 - link
I'm going to assume that's code for "writing an awesome performance midrange buyers guide."[hint]
jgv115 - Monday, November 21, 2011 - link
Will this include G1 drives?Roland00Address - Monday, November 21, 2011 - link
G2 drives on the other hand do have trimmooninite - Monday, November 21, 2011 - link
Linux has had support for RAID and TRIM for quite some time. The support is also agnostic to the vendor of the SSD. I have two Intel SSDs in RAID-0 and TRIM has been working fine for me.P.S. Linux also supports encryption and TRIM. It's relatively new, and not fully secure, but it exists.
Makaveli - Monday, November 21, 2011 - link
Interesting.This is a reason to buy a Second 160GB G2.
320GB of Storage with raid 0 is very tempting.
Wisq - Saturday, April 14, 2012 - link
Linux has supported TRIM with LVM for a couple years, but mdraid support is still in the process of being added, with a set of patches submitted only last month.http://comments.gmane.org/gmane.linux.kernel/12654...
LVM and mdraid use different codepaths, so there's been some confusion on this matter. But yes, I have used an LVM-striped setup (which is essentially software RAID0) since late last year, and TRIM is working.
If you're using mdraid, check your dmesg for "discard not supported, disabling". Linux won't throw an error if you ask for TRIM and you can't get it, it'll just disable it.
TheDudeFoo - Monday, November 21, 2011 - link
I have a AMD motherboard with SB850 running my SATA's - there may be a marvell controller for extra ports but the whole thing is AMD.AM I SOL?
Kristian Vättö - Tuesday, November 22, 2011 - link
At least at this point, you are SOL. AMD/Marvell may release an update, though.MajesticXII - Tuesday, November 22, 2011 - link
So will this only work on Intel SSDs or will it work for other brands that are connected to the Intel SATA controller?I ask because I have 2 128GB Crucial M4s in RAID0 on the 6Gbps Intel controller on my P8Z68.
etamin - Tuesday, November 22, 2011 - link
Is TRIM supported for RAID 1?etamin - Tuesday, November 22, 2011 - link
nvm...already discussed in other commentsXplorer4x4 - Friday, November 25, 2011 - link
Looks like this will be coming in RST 11.5 release.http://communities.intel.com/message/143346#143346
inoshiro - Wednesday, January 25, 2012 - link
Would you agree that TRIM cannot be used in the following situations:1. Server virtualization environment: For instance, we install VMware ESXi on a host, and a couple of virtual servers in it. Since TRIM works on deleted files, and files here are VMware virtual disks, the TRIM doesn't help when guest OS deletes files, until the whole virtual disk is deleted.
2. SSD in a Database Server: Again the same, the data in databases is deleted, but the DB datafiles rarely. As long as no file is deleted, TRIM doesn't fire.