Re: SLES 15 seems to work well as a PV guest

[Harry Waddell <waddell%caravaninfotech.com@localhost>]

On Thu, 16 Aug 2018 08:04:43 +0530
"Cherry G. Mathew" <cherry%NetBSD.org@localhost> wrote:

> Harry Waddell <waddell%caravaninfotech.com@localhost> writes:
> 
> > I've had a LOT of issues with SLES 12 guests and have been running them as HVM guests
> > as a result. As of xen 4.8.3, I've even had to convert some of my newer SLES 11 systems 
> > to HVM as well. Adding insult to injury, I've had to disable the PVHVM drivers on the HVM 
> > guests too. Even with all the special care I've given these systems, they tend to hang 
> > a lot more than 100+ non-netbsd domUs I run. 
> >
> > As a very pleasant surprise, SLES 15 seems quite PV friendly on a NetBSD 7-release dom0
> > with both xen 4.6.3 and 4.8.3. Just boot the install kernel PV and do a network install and 
> > everything just seems to work. For example I zero out the unused blocks before making a
> > backup of the LVM post initial setup:
> >
> > dd if=/dev/zero of=foofile bs=1024k; rm -rf foofile ; poweroff
> > dd: error writing 'foofile': No space left on device
> > 16087+0 records in
> > 16086+0 records out
> > 16867397632 bytes (17 GB, 16 GiB) copied, 37.6223 s, 448 MB/s
> >
> > which is pretty good given that writing to an lvm device from dom0 yields about 500MB/s.
> >
> > RHEL/Centos 7.x and Ubuntu 16 continue to work well in PV as before. 
> >
> > HW
> >  
> 
> Hello Harry - thanks for the feedback  - I've begun work on fixing a
> bunch of things that might have affected you previously. I hope to
> report here weekly, so what would be really nice is if you (and others)
> could help with testing patchsets that I'm likely to throw out here in
> the coming weeks.
> 
> Many Thanks,
> -- 
> ~cherry
> 

Are these changes to the xen tools, xen kernel, or the netbsd dom0 kernel? All of the above!?

I have enough flexibility that I should be able to do some testing. I've got a small xeon E3 system
with about 32GB of ram and a 256GB SSD, which for the time being, I can use for testing. It's 
running 4.11 and netbsd-8 release at present. The bigger systems are running 7-release and 
production vms, but if we have something that looks beta quality at least, I can 
test on those if I schedule some downtime. ( all the developer vms on on one system
just for this purpose as they have a differnet SLA than everything else )

HW