Where is my memory on 'fresh' 11-STABLE? It should be used by ARC, but it is not used for it anymore.

[Eugene M. Zheganin]

Hello,

20.11.2018 15:42, Lev Serebryakov пишет:
>   I have server which is mostly torrent box. It uses ZFS and equipped
> with 16GiB of physical memory. It is running 11-STABLE (r339914 now).
>
>   I've updated it to r339914 from some 11.1-STABLE revision 3 weeks ago.
>
>   I was used to see 13-14GiB of memory in ZFS ARC and it was Ok.
> Sometimes it "locks" under heavy disk load due to ARC memory pressure,
> but it was bearable, and as ZFS is main reason this server exists, I
> didn't limit ARC.
>
>   But new revision (r339914) shows very strange behaivor: ARC is no more
> than 4GiB, but kernel has 15GiB wired:
>
> Mem: 22M Active, 656M Inact, 62M Laundry, 15G Wired, 237M Free
> ARC: 4252M Total, 2680M MFU, 907M MRU, 3680K Anon, 15M Header, 634M Other
>       2789M Compressed, 3126M Uncompressed, 1.12:1 Ratio
>
>   It is typical numbers for last week: 15G wired, 237M Free, but only
> 4252M ARC!
>
>   Where is other 11G of memory?!
>
> [...]
>   And total USED/FREE numbers is very strange for me:
>
> $ vmstat -z | tr : , | awk -F , '1{u+=$2*$4; f+=$2*$5} END{print u,f}'
> 5717965420 9328951088
> $
>
>   So, only ~5.7G is used and 9.3G is free! But why this memory is not
> used by ARC anymore and why is it wired and not free?
I'm getting pretty much same story on recent 11-STABLE from 9th 
November. Previous versions didn't have that much questions about memory 
usage (and I run several 11-STABLEs).

Eugene.