umount() taking minutes for FUSE filesystems

[Conrad Meyer]

Hey Nikolaus,

A first cut debug tactic might be running 'procstat -kk <pid of
printcap process>' to see where it is spending time in the kernel.  I
haven't had time to try and reproduce this myself, sorry.

Best,
Conrad

On Tue, Aug 29, 2017 at 1:57 AM, Nikolaus Rath <Nikolaus at rath.org> wrote:
> *ping*
>
> Anyone able to help?
>
> Thanks,
> -Nikolaus
>
> On Aug 24 2017, Nikolaus Rath <Nikolaus at rath.org> wrote:
>> Hello,
>>
>> It seems that in some situations, the unmount() system call takes
>> minutes to unmount fuse filesystems. To reproduce, download a Git
>> snapshot of libfuse 3 from https://github.com/libfuse/libfuse and do:
>>
>> $ md build; cd build
>> $ meson ..
>> $ mesonconf -D buildtype=debug # optional
>> $ ninja
>>
>> Then execute examples/printcap. This will take very long, and all the
>> time is spent in the unmount(mountpoint, MNT_FORCE) call in
>> mount_bsd.c:fuse_kern_unmount().
>>
>> Does anyone have an idea what might be causing this and how to fix it?
>>
>> My hunch is that it has something to do with libfuse no longer
>> responding to requests at this point. But I'm at my wits end as to why
>> and what to do about it....
>>
>> Best,
>> -Nikolaus
>>
>> --
>> GPG Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F
>>
>>              »Time flies like an arrow, fruit flies like a Banana.«
>> _______________________________________________
>> freebsd-fs at freebsd.org mailing list
>> https://lists.freebsd.org/mailman/listinfo/freebsd-fs
>> To unsubscribe, send any mail to "freebsd-fs-unsubscribe at freebsd.org"
>
>
> --
> GPG Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F
>
>              »Time flies like an arrow, fruit flies like a Banana.«
> _______________________________________________
> freebsd-fs at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-fs
> To unsubscribe, send any mail to "freebsd-fs-unsubscribe at freebsd.org"