TRIM command (as it applies to SSD) and the vanilla arch kernel

graysky · 2009-08-14 19:43:16

According to this wikipedia article, the TRIM command has been implemented in Linux since kernel version 2.6.28. I'm wondering if the vanilla Arch kernel (x86_64) has support for this compiled in and if so which module would one need to modprobe to use it?

Thanks!

sip03ds · 2009-08-15 03:57:52

You SSD must have its firmware updated in order to support the TRIM command

djszapi · 2009-08-15 07:01:55

Hello graysky!

Yeah in case of older you need for updating, but what's the exact problem ? Can't you find such a ciommand or some error output after trying this command ?

graysky · 2009-08-15 09:19:21

The 2nd gen Intel SSD has TRIM support. I just want to be sure that my kernel is using it natively and that it is setup properly before I format the SSD.

Malstrond · 2009-08-15 16:17:20

I'm using a OCZ Vertex FW 1.40 and I was wondering about this myself. It seems to completely lack any documentation.

djszapi wrote:

after trying this command

Well, it's not that easy, it's an ATA command, sent from the kernel to the I/O controller, not like just entering mv x y. I don't have much of a clue about the ioctls you'd need to run this command manually, IOCTL_ATA_PASS_THROUGH_DIRECT sounds good, but I have no idea about what it really does or how it works.

graysky · 2009-08-22 10:37:16

hmmmm... is NOMMU_INITIAL_TRIM_EXCESS the so-called "TRIM" support in the kernel?

R00KIE · 2009-08-22 14:24:58

graysky wrote:

hmmmm... is NOMMU_INITIAL_TRIM_EXCESS the so-called "TRIM" support in the kernel?

I don't think so, that seems to be memory (ram) related (NOMMU.... MMU is related to memory access as far as I know).

All I could find with a quick google search were a few posts saying there are submitted patches and some scripts .... nothing too certain.
As always things seem to be going at the windows development speed instead of the pace technology could go, also it seems that the spec for the trim command is/was still being finalized.

http://www.linuxquestions.org/questions … ux-713006/
http://marc.info/?l=linux-kernel&m=124169431911648&w=2
http://forum.soft32.com/linux/Linux-ATA … 83626.html
http://www.ocztechnologyforum.com/forum … fb&t=60882

graysky · 2009-08-23 10:02:53

Thanks for the links. Guess I'll hold off on purchasing the SSD until this gets spelled out. According to what I've read, the ability to use TRIM is absolutely key in prevent performance degradation long-term. There are other links but you get the idea.

Clean Drive                   13.1 MB/s
Used Drive                     6.9 MB/s
Used Drive After TRIM         12.9 MB/s

EDIT: Judging by the readme.txt in Mark Lord's wiper.sh TRIM isn't mainstreams yet (btw, Mark Lord is the hdparm guy):

Once there are drives in the marketplace with production firmware that supports the SATA DSM TRIM command, then this will get tested a bit more over time. As that happens, it will be moved out of this directory and installed alongside the hdparm executable, probably under /sbin or /usr/sbin.

Also, if your read Mark's the replies in the ocztech link you posted, he alludes to the fact that there is currently (Aug/2009) prototype in-kernel native-TRIM code.

Last edited by graysky (2009-08-23 10:50:23)

Arch Linux

#1 2009-08-14 19:43:16

TRIM command (as it applies to SSD) and the vanilla arch kernel

#2 2009-08-15 03:57:52

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#3 2009-08-15 07:01:55

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#4 2009-08-15 09:19:21

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#5 2009-08-15 16:17:20

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#6 2009-08-22 10:37:16

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#7 2009-08-22 14:24:58

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

#8 2009-08-23 10:02:53

Re: TRIM command (as it applies to SSD) and the vanilla arch kernel

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