On Tue, Jun 16, 2015 at 06:33:34PM +0200, Igor Mammedov wrote: > Series extends vhost to support upto 509 memory regions, > and adds some vhost:translate_desc() performance improvemnts > so it won't regress when memslots are increased to 509. > > It fixes running VM crashing during memory hotplug due > to vhost refusing accepting more than 64 memory regions. > > It's only host kernel side fix to make it work with QEMU > versions that support memory hotplug. But I'll continue > to work on QEMU side solution to reduce amount of memory > regions to make things even better. I'm concerned userspace work will be harder, in particular, performance gains will be harder to measure. How about a flag to disable caching? > Performance wise for guest with (in my case 3 memory regions) > and netperf's UDP_RR workload translate_desc() execution > time from total workload takes: > > Memory |1G RAM|cached|non cached > regions # | 3 | 53 | 53 > ------------------------------------ > upstream | 0.3% | - | 3.5% > ------------------------------------ > this series | 0.2% | 0.5% | 0.7% > > where "non cached" column reflects trashing wokload > with constant cache miss. More details on timing in > respective patches. > > Igor Mammedov (5): > vhost: use binary search instead of linear in find_region() > vhost: extend memory regions allocation to vmalloc > vhost: support upto 509 memory regions > vhost: add per VQ memory region caching > vhost: translate_desc: optimization for desc.len < region size > > drivers/vhost/vhost.c | 95 +++++++++++++++++++++++++++++++++++++-------------- > drivers/vhost/vhost.h | 1 + > 2 files changed, 71 insertions(+), 25 deletions(-) > > -- > 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
