[Libguestfs] [nbdkit PATCH v2 13/13] RFC: plugins: Add callbacks for FUA semantics

[Richard W.M. Jones]

On Fri, Jan 19, 2018 at 12:41:01PM -0500, Shaun McDowell wrote:
[...]

Thanks for the other email, I thought it was very interesting and I'm
glad that people are looking at the performance of nbdkit seriously.

> Our cbdkit was branched from 1.1.12 with some patches from 1.1.13 added as
> well. The project has morphed significantly enough that a direct diff or
> merging between the two would not be feasible. Even the structure of the
> project directory and build has been changed to be in line with our other
> internal projects.
> 
> I have uploaded the entire cbdkit source to our github at
> https://github.com/dev-cloudbd/cbdkit
[...]

As you say the structure is quite a lot different, making it difficult
for me to use any of this work at the moment.  I do have a couple of
questions though ...

- Is a multithreaded approach (as Eric has now implemented) completely
out of the question?  I'm guessing the problem will be with memory
usage for all of those thread stacks.  You mentioned memory usage of
100MB and maybe that's important for your cloud use case?

- Are you going to try to pull any changes from upstream nbdkit or is
the fork now too large to try?

I think if you wanted to get any of this upstream [it wasn't really
clear if you do, and of course licensing-wise it's entirely optional
for you to release any changes at all], but if you did then maybe see
if there are simple patches that could go first.

Rich.

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