Help us to find a public patch

olivierlambert

Hey there!

I would need a hand to find a patch done by Citrix on QEMU, to fix a performance problem using SMAPIv3 and qcow2 image format.

You can read the issue I created there: https://github.com/xapi-project/xapi-storage/issues/91

As you can see, it seems I got a relatively cold welcome regarding how to find the patch. I don't understand why, but anyway, it's not the point. If it's true, it means the patch is around the QEMU-devel mailing list.

I don't know what to search exactly, but we can probably search something related to performances issues, posted by an email of Citrix. And it should have been done in the last months (I would say not earlier than May).

If you find possible candidates, let me know!

olivierlambert created this issue in xapi-project/xapi-storage

closed SMAPIv3 performance #91

Danp

@olivierlambert Only thing I found that was associated with Citrix is this --

https://lists.nongnu.org/archive/html/qemu-devel/2017-04/msg04626.html

olivierlambert

This one sounds too low level, more purely Xen oriented.

Danp

What about this one?

https://lists.nongnu.org/archive/html/qemu-devel/2018-02/msg00911.html

olivierlambert

I've read it, and I'm not sure at all. Also the contributor doesn't seem to work for Citrix at all

DustinB

This is the only mention of storage performance drops that I can find.

http://lists.nongnu.org/archive/html/qemu-devel/2018-05/msg06173.html

olivierlambert

Not convincing either. Damn, I'd like to have at least a hint from Citrix on where to look

olivierlambert

Okay so I spent more than an hour to search something to finally get this answer:

It's probably gone internally as I believe the upstream maintainer for that part is also an employee or it's still undergoing internal review, all I know for sure is it's fixed.

Fantastic. So the "upstream" is also done internally. That will be really easy to contribute

buzzzo

@olivierlambert my idea is that soon or later citrix will close all the XenServer's development.
Clear signs of it is keeping long awaited feature like thin provision closed source.
If this thing will become true xcp would turn itself in a independent fork in order to continue its life.

olivierlambert

That's a possibility yes. I don't think it could happen fast however. And you can't close existing opened code, so it will be more proprietary additions in the end.

That's why we are innovating directly in XCP-ng, and we'll continue that way!