Chris Samuel <[email protected]> writes: > On 09/11/12 11:07, Trent W. Buck wrote: > >> Also ssd_sparse IIRC, for a different flavour of FTL. >> It's not very clear to me how to know which of the two to use. > > Aha, ssd_spread, looks like it's meant for lower grade SSD's.
What does that actually mean in practice, though? Once upon a time, it was intel, or <everything else>. Even if you can determine that your OCZ Vertex NN runs a Sandforce MM chipset, which do you use? Maybe the rule of thumb is to use ssd for SSDs, and ssd_spread for USB keys and SD/MMC cards? > samuel@eris:~/Downloads/linux$ git log -Sssd_spread fs/btrfs/ > commit 451d7585a8bb1b9bec0d676ce3dece1923164e55 > Author: Chris Mason <[email protected]> > Date: Tue Jun 9 20:28:34 2009 -0400 > > Btrfs: add mount -o ssd_spread to spread allocations out > > Some SSDs perform best when reusing block numbers often, while > others perform much better when clustering strictly allocates > big chunks of unused space. > > The default mount -o ssd will find rough groupings of blocks > where there are a bunch of free blocks that might have some > allocated blocks mixed in. > > mount -o ssd_spread will make sure there are no allocated blocks > mixed in. It should perform better on lower end SSDs. > > Signed-off-by: Chris Mason <[email protected]> _______________________________________________ luv-main mailing list [email protected] http://lists.luv.asn.au/listinfo/luv-main
