FreeBSD/ZFS on [HEAD] chews up memory

[Mark Martinec]

2015-04-09 15:19, Bob Friesenhahn wrote:
> On Thu, 9 Apr 2015, grarpamp wrote:
>>> RAM amount might matter too. 12GB vs 32GB is a bit of a difference.
>> Allow me to bitch hypothetically...
>> We, and I, get that some FS need memory, just like kernel and
>> userspace need memory to function. But to be honest, things
>> should fail or slow gracefully. Why in the world, regardless of
>> directory size, should I ever need to feed ZFS 10GB of RAM?
> 
> From my reading of this list in the past month or so, I have seen
> other complaints about memory usage, but also regarding UFS and NFS
> and not just ZFS.  One is lead to think that the way the system uses
> memory for filesystems has changed.
> 
> As others have said, ZFS ARC should automatically diminish, but
> perhaps ZFS ARC is not responsible for the observed memory issues.
> 
> Bob

I'd really like to see the:

   [Bug 187594] [zfs] [patch] ZFS ARC behavior problem and fix
     https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=187594

find its way into 10-STABLE. Things behaved much more
sanely some time in 9.*, before the great UMA change
took place. Not everyone has dozens of gigabytes of memory.
With 16 GB mem even when memory is tight (poudriere build),
the wired size seems excessive, most of which is ARC.

   Mark