[zfs-discuss] SSD write buffer to increase write speed and IOPS

Ryan How ryan at zbit.net.au
Thu Oct 31 19:58:09 EDT 2013

On 31/10/2013 11:00 PM, Reinis Rozitis wrote:
>> Or are there any other technologies about? Surely someone has 
>> invented an SSD write buffer?
> While its not ZFS related there is bcache ( 
> http://bcache.evilpiepirate.org/ ), flashcache ( 
> https://github.com/facebook/flashcache ) and EnhanceIO ( derived from 
> flashcache https://github.com/stec-inc/EnhanceIO  ) and you are 
> probably looking to the Writeback caching mode  (fastest but less 
> safe) - writes only go to the ssd initially, and based on various 
> policies are written to disk later. All disk reads are cached (tunable).
> Though I haven’t played too much around with theese to comment on 
> which is better or what the caveats are.

If the cache drives run on a redundant zpool of SSDs I imagine the 
writeback cache would be pretty safe, assuming the code doesn't have 
bugs and ensures transactional consistency, which seems to be what they 

Has anyone tried any of these? It seems the setup would start getting a 
bit fiddly?

Thanks, Ryan

To unsubscribe from this group and stop receiving emails from it, send an email to zfs-discuss+unsubscribe at zfsonlinux.org.

More information about the zfs-discuss mailing list