[Borgbackup] Did anyone ever test SSHFS with FUSES's NOFORGET-option?

[Bzzzz]

On Tue, 6 Jul 2021 21:39:05 +0200
Thorsten Schöning<tschoening at am-soft.de> wrote:

> https://borgbackup.readthedocs.io/en/stable/faq.html#why-is-backup-slow-for-me
> 
> After looking at your issue tracker and stuff, whenever people ran
> into that problem and SSHFS really was the issue, instead of changing
> mount points or alike, I couldn't find the options people used SSHFS
> with.
> 
> The point is that FUSE supports two interesting options: "use_ino",
> which is documented to allow the file system to "set" inodes. OTOH,
> I've read that SSHFS is based on SFTP, which doesn't provide inodes at
> all. So "set" might really be meant as it is, like a value not being
> available when only read in this setup.
> 
> > -o use_ino
> > let filesystem set inode numbers
> 
> https://linux.die.net/man/1/sshfs
> 
> But there's additionally the option "noforget" and that doesn't seem
> to even be documented for SSHFS:
> 
> > Never forget cached inodes
> 
> https://www.fsl.cs.stonybrook.edu/docs/fuse/fuse-article-appendices.html
> 
> And here's the interesting part: I've found someone describing inode
> related problems with GIT and SSHFS and "noforget" seems to have fixed
> those:
> 
> > Fuse version 2.8.x has a "noforget" option that should provide stable
> > inode numbers, at the cost of unbounded memory use. Could you please
> > try if this option fixes these issues?
> 
> https://git.vger.kernel.narkive.com/L4f8hTjT/inode-problem-when-using-git-on-a-sshfs-filesystem#post3
> https://git.vger.kernel.narkive.com/L4f8hTjT/inode-problem-when-using-git-on-a-sshfs-filesystem#post4
> 
> As both mentioned options are disabled by default accoridng the docs,
> I wondered if it's known that those have been explicitly tested ever?
> 
> Or is it known already that those can't work with Borg?
> 
> Especially the latter reads to me like FUSE is calculating inodes
> somehow on its own and those are stable then onyl for a longer period
> of time. But I couldn't find how those are calculated especially with
> SSHFS and how long those would be valid. I guess only for how long a
> file system is mounted?

Type: borg help create
and look for the "--files-cache" section.

Jean-Yves