[gentoo-user] trim for ssds

[gentoo-user] trim for ssds

[Maxim Wexler]

According to

http://en.wikipedia.org/wiki/TRIM_%28SSD_command%29

trim has been implemented in the 28 kernel.  Anybody know what the
option is called? It ain't 'trim'.

Maxim

Re: [gentoo-user] trim for ssds

[Stroller]

On 6 Sep 2009, at 22:21, Maxim Wexler wrote:
> According to
>
> http://en.wikipedia.org/wiki/TRIM_%28SSD_command%29
>
> trim has been implemented in the 28 kernel.  Anybody know what the
> option is called? It ain't 'trim'.

It won't be a userspace command that you can type in at the command  
prompt, the way you can type `ls` or `cp`.

The TRIM command is sent by the _kernel_ to the drive, and there will  
be no human interaction involved in issuing it (other than removing a  
file with `rm /path/to/file`).

Stroller.

[gentoo-user] Re: trim for ssds

[walt]

On 09/06/2009 02:21 PM, Maxim Wexler wrote:
> According to
>
> http://en.wikipedia.org/wiki/TRIM_%28SSD_command%29
>
> trim has been implemented in the 28 kernel.  Anybody know what the
> option is called? It ain't 'trim'.

First, thanks for the link, which led me to lwn.net.  Those guys have
some serious talent and skills that I didn't know about before.

I found a post there from a year ago, saying this:

Part of the problem is that the ATA TRIM command isn't fully specified
yet, so we'll need to allocate a temporary command to test it.  This
also means that no existing device on the market can take advantage of it.

Just by grepping through the linux kernel sources I can see that the
kernel automatically does a test to discover if the disk is a SSD, so
you don't need to do anything special to make the kernel do that.

How effective that is for extending the life of a SSD, I have no clue.

Re: [gentoo-user] Re: trim for ssds

[Stroller]

On 7 Sep 2009, at 00:07, walt wrote:
> On 09/06/2009 02:21 PM, Maxim Wexler wrote:
>>
>> http://en.wikipedia.org/wiki/TRIM_%28SSD_command%29
>
> ...How effective that is for extending the life of a SSD, I have no  
> clue.

Uh, extending the life of the SSD isn't the purpose.

http://www.anandtech.com/storage/showdoc.aspx?i=3531&p=10
(you really need to read the whole, LONG, article, starting at <http://www.anandtech.com/storage/showdoc.aspx?i=3531 
 > to fully understand how SSDs work & the point of trim)

Stroller.

[gentoo-user] Re: trim for ssds

[walt]

On 09/07/2009 08:00 AM, Stroller wrote:
>
> On 7 Sep 2009, at 00:07, walt wrote:
>> On 09/06/2009 02:21 PM, Maxim Wexler wrote:
>>>
>>> http://en.wikipedia.org/wiki/TRIM_%28SSD_command%29
>>
>> ...How effective that is for extending the life of a SSD, I have no clue.
>
> Uh, extending the life of the SSD isn't the purpose.
>
> http://www.anandtech.com/storage/showdoc.aspx?i=3531&p=10
> (you really need to read the whole, LONG, article, starting at
> <http://www.anandtech.com/storage/showdoc.aspx?i=3531> to fully
> understand how SSDs work & the point of trim)

Great article(s), and a fascinating website.  That makes two good
sites I've discovered in this one short thread.