Re: RFC reviews for ggate and hastd

From: John-Mark Gurney <jmg_at_funkthat.com>
Date: Mon, 20 Sep 2021 15:36:31 -0700
Johannes Totz wrote this message on Sun, Sep 19, 2021 at 17:27 +0100:
> On 14/09/2021 22:21, John-Mark Gurney wrote:
> > Johannes Totz wrote this message on Mon, Sep 13, 2021 at 02:00 +0100:
> >> On 09/09/2021 23:33, John-Mark Gurney wrote:
> >>> Johannes Totz via freebsd-geom wrote this message on Thu, Sep 02, 2021 at 21:55 +0100:
> >>>> (looks like gmane swallowed my 1st message, trying again)
> >>>>
> >>>> Hey folks,
> >>>>
> >>>> any ggate or hastd users here? I've got some code reviews for you.
> >>>> Please take a look if you get a chance:
> >>>>
> >>>> https://reviews.freebsd.org/D31727
> >>>> Fix potential out-of-bounds read in the geom-gate kernel module.
> >>>>
> >>>> https://reviews.freebsd.org/D31722
> >>>> Dynamically alloc buffers in ggatec, instead of assuming a fixed size on
> >>>> the stack.
> >>>>
> >>>> https://reviews.freebsd.org/D31709
> >>>> Simple rc script to start ggated.
> >>>
> >>> I'll try to look at them.
> >>>
> >>> I've broken out the ggate code to: https://www.funkthat.com/gitea/jmg/ggate
> >>
> >> Nice, thanks!
> >>
> >> I noticed the http branch. One weekend toy project idea I wanted to get
> >> around to was to write a ggated impl that talks to Backblaze.
> > 
> > I looked at the Backblaze B2 API, and I don't see a way to do partial
> > updates of a file.  All the API that I see require you to upload the entire
> > file, so I don't think that it'll work.
> > 
> > I abanded http as a solution, because of issues w/ WebDAV and partial
> > updates and the IETF not being very sane about it:
> > https://blog.sphere.chronosempire.org.uk/2012/11/21/webdav-and-the-http-patch-nightmare
> 
> Oh I was just gonna store each block as a separate file on the backend. 
> No need to keep it all together as one huge image. Sure we'd end up with 
> literally billions of small files. But I'd ignore that until it becomes 
> an actual problem.

Ahh, guess that'd work.

It'd be interesting to see what the performance would be storing them
as 512 byte files/blocks, or 4k files (and presenting a 4k block size),
or 64k byte files, but still doing a 4k block size, and doing a RMW
style caching for the larger blocks.  gcache may be able save the work
of writing a proper caching layer for it...

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."
Received on Mon Sep 20 2021 - 22:36:31 UTC

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