"Ask and thou shalt receive" :-)

We have been working on a FUSE-based mechanism for Coda, and should
have a release in the near future.  There is a noticeable performance cost
relative to using a kernel module, so I see the kernel module as continuing
to be very valuable well into the future.   That said, having FUSE as a way
to get going quickly on a platform if you don't have a kernel module is valuable.
Jan can give more details on the implementation and comment on when
a release might be available.  Maybe in time for Santa's visit :-)

   ---- Satya









On Wednesday 21 November 2018 17:07:10 Brett Lymn wrote:
> On Wed, Nov 21, 2018 at 05:55:40PM +0100, u-x417_at_aetey.se wrote:
> > 
> > (Don't most file systems need their specific kernel modules? Good or not
> > but isn't this the status quo?)
> > 
> 
> A lot of them are tradition... I am pretty sure that NFS on Linux is all
> userland.
> 
> > > NetBSD has just discussed whether to
> > > remove coda kernel support, as it has almost no users.  For now, it is
> > > staying.
> > 
> > Oh! I depend on Coda being available on NetBSD. Hope it continues to.
> > 
> 
> Well, there is at least one developer that uses it....So lossage get
> noticed at some point, depending on how much hack time they have.
> 
> > This is imho what really should be fixed, FUSE or not.
> > 
> > With all due and enormous respect to the early developers, this
> > communication channel is flaky, both in design (ioctl is a really bad
> > tool, given that we handle a pure IPC/RPC between user processes and
> > venus; the only role of the kernel is to help process authentication,
> > not having to be aware of the data to be passed) and as a result also
> > flaky in the implementation.
> > 
> 
> No, the kernel module does a lot more than that, at least on NetBSD,
> the kernel module hooks into the UFS code to perform directory
> processing and a few other things.  In fact this hooking resulted in a
> very long standing bug in the NetBSD venus process where coda and ufs
> disagreed on the size of a directory block size - this caused directory
> entries to "disappear".
> 
> > 
> > Frankly I doubt whether FUSE would make a big difference. We have already
> > kernel support for Coda in Linux, NetBSD, FreeBSD. Which platform would
> > you look forward to, which has a usable FUSE but a different kernel than
> > one of the above?
> > 
> 
> From wikipedia - OpenBSD, OpenSolaris, Minix 3, Android, MacOS.
> 
> If FUSE support was built into venus then, potentially, coda would be
> able to run on these operating systems too... I don't know how useful it
> would be but Coda on a phone would be pretty cool ;)
> 
>