Re: Speed improvements in ZFS

Am 2023-08-20 19:10, schrieb Mateusz Guzik:
> On 8/18/23, Alexander Leidinger <Alexander@leidinger.net> wrote:

>> I have a 51MB text file, compressed to about 1MB. Are you interested 
>> to
>> get it?
>> 
> 
> Your problem is not the vnode limit, but nullfs.
> 
> https://people.freebsd.org/~mjg/netchild-periodic-find.svg

122 nullfs mounts on this system. And every jail I setup has several 
null mounts. One basesystem mounted into every jail, and then shared 
ports (packages/distfiles/ccache) across all of them.

> First, some of the contention is notorious VI_LOCK in order to do 
> anything.
> 
> But more importantly the mind-boggling off-cpu time comes from
> exclusive locking which should not be there to begin with -- as in
> that xlock in stat should be a slock.
> 
> Maybe I'm going to look into it later.

That would be fantastic.

Bye,
Alexander.

-- 
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