[arch-general] ssd

[Juan Diego Tascón]

On Tue, Oct 30, 2012 at 6:32 PM, André Prata <bugflux at gmail.com> wrote:

> On Tue, Oct 30, 2012 at 10:52 PM, Gaetan Bisson <bisson at archlinux.org
> >wrote:
>
> > [2012-10-29 21:58:01 -0500] Juan Diego Tascón:
> > > I just got a new laptop with a 25Gb ssd and I was wondering which would
> > be
> > > best if putting my home directory (minus music and videos) there or and
> > > arch install (minus pacman pkg cache). I read the ssd related article
> in
> > > the wiki and even though it mentions some optimizations and
> > considerations
> > > it doesn't mention anything regarding this issue.
> >
> > With a high-quality SSD you do not really need to do anything.
> >
> > With a generic SSD, you should reduce the number of writes or spread
> > them out evenly on all sectors. The latter can be achieved by using file
> > systems such as nilfs2. The former can be achieved by disabling system
> > logging or making /var/log a tmpfs, and more generally by controlling
> > write-hogs (think of XDG_CACHE_HOME, ~/.mozilla, etc.).
> >
> > But of course I cannot tell you as much as all the information many
> > people have put on the Internet over time on that topic.
> >
> > --
> > Gaetan
> >
>
> I think the question is not as how to prolong the life of the disk, but
> rather how to take advantage of such a small space with high throughput.
>
> Well, I guess that it's really hard to tell if you would benefit more from
> having your system or your user files in the SSD, if there is no space for
> both. In case of lodging the system there, you would benefit from faster
> boot times, and some program calls. However, if you have a large memory
> system, it will account less and less towards greater uptimes. If that is
> the case, your personal files would be a better fit.
>
> One third option, although I'm not sure of the reliability or of the raw
> efficiency increase, would be to use the 25GB as a cache for everything
> else, with gimmicks such as flashcache [1] or bcache [2].
>
> Or just google something like "SSD as a cache".
>
> [1] https://github.com/facebook/flashcache
> [2] http://lwn.net/Articles/458417/
>
>
> André Prata
> http://about.me/andreprata


Yes my question was more oriented towards the kind of answer you just gave
me. To conclude I think I'll relocate my home directory to the ssd.

One more question regarding the first answer: how can I tell if my ssd is
high quality? are there any tests? or maybe a references-features list? or
maybe some utility to fetch ssd info?

Thanks to both of you