Re: Ongoing data reorganization/defragmentation?

On 12.09.2012 20:15, Lukáš Czerner wrote:

On Wed, 12 Sep 2012, norritt@t-online.de wrote:

 From what I've found out it's a good idea to:
- mount with noatime, discard (if drive supports trim)
The -o discard option might be tricky since some devices still
handles it quite badly and you can experience big performance drops
(http://people.redhat.com/lczerner/discard/ although it is somewhat
outdated already). But you might to try to see yourself if it does
not hurt your performance.

The other option would be to use batched discard with fstrim (see
fstrim from util-linux) and run it once per (day, week, month).

Thanks!
-Lukas

Hi  Lukáš,
thank you for pointing out the performance issue with the discard mount 
option, I hadn't read about that yet. As far is I know I'm using a quite 
special SSD (SanDisk, with a SanDisk controller), where most other SSDs 
on the market seem to be based on Marvell, Sandforce or Indilinx 
controllers. I saw that you were using SSDs from various vendors for 
your benchmarking tests. Was a model with SanDisk controller among the 
drives you tested? Would postmark data about disks with SanDisk 
controller be of interest to you?

Regards Nor
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