[Tfug] SSD plans & disk usage

[Tom Rini]

On Mon, Jan 17, 2011 at 5:38 PM, Louis Taber <ltaber at gmail.com> wrote:
> Hi All,
>
> My plan is to use the SSD as the root device and /usr to help system
> performance.   I have two 640GByte drives that I am planning on mirroring
> the rest of the system with and a 250GByte drive for "secondary" backup.
> /var, & /home  will definitely not be on the SSD drive.  My plan is to use
> the SSD for booting and executable binary  to speed up the overall system.
> On my current system / and /usr total 9.704GBytes.
>
> The amount of activity on the my log device should be low enough that
> placing /var on a SSD would make little difference.
> In the last 11 hours my system has written 54 lines totaling 3626 bytes to
> /var/log/syslog --  54 writes in 11 hours.
>
> Has anyone seen any statistics, or know how to acquire them easily on
> various partitions to see if my plan will result in any obvious improvement
> in system performance?  (Is the kernel keeping track of reads and writes by
> partition?)  It might just be a waste of money <sigh>.

Well, what are your workloads?  iirc the big performance win from
executions is when they've got a lot of data files to read (ie games),
or if you're going to fire up gimp on stuff that's on SSD.  They're
also quite good at speeding up your life if you're going to be
reading/writing to them a lot (I know folks that use them for build
space at work where there's an understanding that yes, the drive will
die at some point sooner than expected, and that's OK).

I guess what I'm driving at is that good SSDs can make use of the
speeds SATA provides but if you aren't doing all that much or all that
much that's intensive it's not going to be a win there.  Of course, if
you're talking about a laptop, the no moving parts and all that is a
win for its own reasons :)

-- 
Tom