ZFS server has gone crazy slow

[Chris Ross]

> On Apr 11, 2020, at 14:33, Eugene Grosbein <eugen at grosbein.net> wrote:
> 
> 12.04.2020 0:36, Chris Ross wrote:
> 
>> I have a FreeBSD 11.3-STABLE server that is my router, using a ZFS mirror (of two GPT disks) as it’s disk.  It’s many years old, and has only been misbehaving like this for a day or so.  I’m trying to figure out what’s wrong.
>> 
>> […]
>> 
>> I _think_ this is a filesystem problem.  It’s very hard to diagnose because logging in, and doing anything, takes many seconds per command.  zpool status shows my mirror as online, so I’m not sure where I should check.
>> 
>> I’d appreciate any help!  Thanks much…
> 
> First of all you should check if any of your ZFS pools is low on space.

Wow.  I’m so embarrassed that I didn’t notice that myself.  You mentioned it, and now I look back at df output and see that the filesystems are all very nearly full!

It’s very slowly booting now, but assumedly after it comes online, I’ll be able to rectify that situation and hopefully that will be the issue.  Thanks, and sorry that I hadn’t seen that myself!

    - Chris