All the memory eaten away by ZFS 'solaris' malloc - on 11.1-R amd64

[Mark Johnston]

On Tue, Jul 31, 2018 at 11:54:29PM +0200, Mark Martinec wrote:
> I have now upgraded this host from 11.1-RELEASE-p11 to 11.2-RELEASE
> and the situation has not improved. Also turned off all services.
> ZFS is still leaking memory about 30 MB per hour, until the host
> runs out of memory and swap space and crashes, unless I reboot it
> first every four days.
> 
> Any advise before I try to get rid of that faulted disk with a pool
> (or downgrade to 10.3, which was stable) ?

If you're able to use dtrace, it would be useful to try tracking
allocations with the solaris tag:

# dtrace -n 'dtmalloc::solaris:malloc {@allocs[stack(), args[3]] =
  count()} dtmalloc::solaris:free {@frees[stack(), args[3]] = count();}'

Try letting that run for one minute, then kill it and paste the output.
Ideally the host will be as close to idle as possible while still
demonstrating the leak.