NFS Mount and LARGE amounts of "INACT" memory

[Larry Rosenman]

On 2015-06-19 19:00, Larry Rosenman wrote:
> On 2015-06-19 18:58, Rick Macklem wrote:
>> Larry Rosenman wrote:
>>> On 2015-06-17 07:26, Larry Rosenman wrote:
>>> > I have a 64G memory FreeBSD 11-CURRENT system that has a couple of
>>> > mounts to a FreeNAS (FreeBSD 9.3) system.
>>> >
>>> > When my rsync from a different system to one of the NFS mounts
>>> > runs, I
>>> > get like 48G of Inactive memory that goes back to
>>> > free if I umount the share.
>>> >
>>> > I'm wondering why this memory moves from ZFS ARC to INACT.
>>> >
>>> > And, is this expected?
>> A wild ass guess would be yes. Assuming you are referring to the NFS
>> client (and not FreeNAS server) and guessing that rsync uses mmap'd
>> I/O...
>> - The pages will be associated with the file's vnode until that vnode
>>   is recycled. (mmap'd I/O can continue after the file is closed.)
>>   This could take a long time.
>> I am not knowledgible w.r.t. the VM subsystem, but I'm guessing that
>> there is some way for these pages to be reused if memory is limited?
>> (Hopefully someone with VM knowledge can comment on this?)
>> 
> Yes, this is the NFS Client, not sure on mmap(2), but that would make 
> sense
> 
> BUT, I don't like that it kills my ZFS ARC....
> 
> VM Guys?
> 
BTW, a quick grep if the rsync sources shows it does NOT use mmap, but 
has some mmap-like routines,
so I'm at a loss....

>> rick
>> 
>>> I've posted screenshots at:
>>> 
>>> http://www.lerctr.org/~ler/FreeBSD_inact/
>>> 
>>> 
>>> --
>>> Larry Rosenman                     http://www.lerctr.org/~ler
>>> Phone: +1 214-642-9640                 E-Mail: ler at lerctr.org
>>> US Mail: 108 Turvey Cove, Hutto, TX 78634-5688
>>> _______________________________________________
>>> freebsd-fs at freebsd.org mailing list
>>> http://lists.freebsd.org/mailman/listinfo/freebsd-fs
>>> To unsubscribe, send any mail to "freebsd-fs-unsubscribe at freebsd.org"
>>> 

-- 
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 214-642-9640                 E-Mail: ler at lerctr.org
US Mail: 108 Turvey Cove, Hutto, TX 78634-5688