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Re: [LUG] SSD and Trim

 

On 16/06/14 10:18, Tremayne, Steve wrote:
> Neil said:
>>> further reading tells me that Trim 
>>> is automatically included with Ubuntu
> 
> Gordon said:
>>> you can manually add
>>>
>>>   discard
>>>
>>> into the /etc/fstab entry for that disk
> 
> Hmmm.
> 
> I'm looking to setup Mint17 on a brand new SSD for my fiancée's laptop, so knowing 
> that it's based on Ubuntu, does discard get added to fstab during the initial 
> installation? If not, at least I know what to look for now. (Thanks Gordon)
> 
> I thought that there was some other program to check / enable Trim too? I'm 
> offline at the moment (sat in a car) at the moment, so can't verify...
> 
> Thanks,
> 
> Steve
> 

Read here:

http://askubuntu.com/questions/18903/how-to-enable-trim

The instructions look a bit bewildering initially but it all boils down
to Ubuntu 14.04 (and thus Mint 17 also) support TRIM out of the box, as
most sane distributions and other operating systems have done for ages.

That being said, Ubuntu/Mint go about it in very strange and irritating
way: a cron job is scheduled to periodically run the TRIM command
(typically once daily). Ubuntu's apparent reasoning behind this is that
certain drives *may* exhibit *some* slowdown under *certain conditions*
whilst deleting many small files *sometimes*.

That's an awful lot of maybes and perhapses, all to justify an odd and
very conservative decision. Everyone on Linux correctly ignores this
frankly bizarre approach and simply adds the "discard" option to the
relevant line in fstab: this is known as the online approach, and is the
only one I have ever known anyone use. I routinely nuke entire massive
(20Gb+) working source code directories full of the many tiny little
files that apparently cause these problems from my SSDs and it's never
been slow - quite the opposite, in fact.

Others were asking about SSD reliability and longevity before - that is
no longer an issue anymore either. I still have an old 8Gb SSD from the
original generation of netbooks in service 5 or 6 years in and it's
still running - as are the mercilessly battered Corsairs/OCZ/Intels in
my workstations and laptops. I thrash these things within an inch of
their life all day, every day, and I'm yet to kill a SSD yet. I have 5
relatively new ones now acting as cache drives for the ZIL and L2ARC
components of my big ZFS server and they are taking a truly epic
battering (1-3 complete writes per day each!) - I'm keeping a close eye
on those because if anything is going to kill a SSD, it's that. Six
months in so far though, and they're all going strong.

YMMV of course, but even if SSDs only lasted 12 months I would still
keep buying them - at well under £1/Gb these days I'd just buy myself a
new set every year, write off the negligible cost and keep enjoying the
unbeatable performance.

Regards

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