[mythtv-users] ZFS - what's the scoop?

[David Brodbeck]

On Oct 17, 2007, at 11:33 AM, John Drescher wrote:

>> is ZFS actually available for Linux now?  i didn't know that it was
>> supported aside from experimentally...
>>
> It is a fuse module so it runs in the userspace instead of the kernel.
> I did some testing a few weeks back and although it has a lot of great
> features there is one very big problem. Performance is very very bad.
> With a zfs filesystem on a linux software raid6 that nets reads at
> 266MB/s and writes over 100 MB/s I was only able to read or write at
> around 20 MB/s and with compression enabled this went down to less
> than 5MB/s. The problem appeared that it was pausing between
> transfers. It also had a high CPU load but not 100%.

I would expect pretty poor performance, since it's running in userspace.

Filesystem compression is not going to be desirable on a Myth media  
drive -- the video is just about as compressed as it can get, already.