Re: [tlug] Making better use of SSDs?: Beware of Heavy Write Usage

[jep200404@example.com]

On Mon, 28 May 2012 10:22:04 +0800, Raymond Wan <rwan.kyoto@example.com> wrote:

> My employer is thinking of purchasing a server and wants to also buy
> an SSD along with it.  I can only think of two ways of making use of
> an SSD under Linux and I was wondering if anyone has better ideas.
> 
> 1)  Well, make it into a drive.  This would only benefit programs that
> have a lot of I/O or programs like Unix's 'sort' which can allow you
> to specify which temporary directory to use.  I can just specify the
> SSD drive.

Yikes!

> 2)  Make it into a swap partition.  This would help if the amount of
> memory used by a program exceeds main memory and it starts paging to
> disk.  Paging to an SSD would surely be faster.  (Assuming it pages
> often...)

Yikes!

Writes wear out SSDs. Better SSDs do a better job of spreading the 
writes out to not prematurely wear out one spot of the drive, 
but still they wear out. A good use of SSDs is for read-only 
or write seldome cachey kind of stuff, like /usr. Using SSDs 
for lots of writes is asking for trouble.