GELI speed

[Eugene Grosbein]

On 29.03.2011 00:57, Clayton Milos wrote:
> Hi Pawel
> 
> I'm running GELI encryption on a hardware RAID5 (8x1TB), formatted to 6.3T 
> usable space using i386 FreeBSD 7.3-PRERELEASE. Write speeds to the drive 
> are just over 40MB/s which is not too bad but I would like to improve it as 
> the drive gets 270MB/s without encryption.
> 
> I've run the following tests:
> dd if=/dev/gzero.eli of=/dev/null bs=1m count=4096
> 4294967296 bytes transferred in 99.763266 secs (43051591 bytes/sec)
> and then
> dd if=/dev/zero of=test.file bs=1m count=1024
> 1073741824 bytes transferred in 26.118988 secs (41109626 bytes/sec)
> 
> There is not much speed lost due to the filesystem throughput or the RAID 
> card.

You can also try increase reading performance by using geom_cache
with sufficiently large cache. It won't impact on linear reads
but for general operations like directory lookups, many short reads etc.
it can decrease number of decrypt requests.

Eugene Grosbein