absurd I/O perf with ZFS: hangs on zfs->cv)

[Eitan Adler]

On 17 January 2013 07:52, Fabian Keil <freebsd-listen at fabiankeil.de> wrote:
> Eitan Adler <lists at eitanadler.com> wrote:
> I don't think there are any laptops with "large amounts of RAM"
> as far as ZFS is concerned.

Haha okay: 8GB of RAM.

>> It is taking me 45 minutes to make 5 commits to git.  Something is
>> wrong here but I have no idea what I should be looking at.  Any ideas?
>
> Try sysutils/zfs-stats to get a rough idea of how ZFS is using
> the available memory.

Anything in particular I should be looking for?

> If you already followed tuning advice from the Internet without
> benchmarking it, try reverting it.

I have done absolutely no tuning.  Is there anything in particular I
*should* tune?

> Once you have gathered some more information it might make sense
> to ask again on freebsd-fs at .

Ack.

> On a new system it's probably not an issue, but the recommendation
> is to keep around 20% of the pool free to keep the performance up.

Good to know.  I will be careful here.


-- 
Eitan Adler