[Qemu-devel] KVM call minutes for Nov 23

[Qemu-devel] KVM call minutes for Nov 23

[Chris Wright]

qcow2 performance roadmap
- What can be done to achieve near-raw image format performance?
  - some discussion points from Kevin on list
    http://lists.nongnu.org/archive/html/qemu-devel/2010-11/msg02126.html
  - please follow up on the list
- some perf numbers (latest upstream qcow2 compared with qed)
  - qed is fully async, added unconditional flush to model qcow2
  - http://wiki.qemu.org/Qcow2/PerformanceRoadmap 
  - qcow2 not scaling as well
    - metadata handling still quite sync
    - sequential reads not scaling at all (a
    - only serialization point is two accesses to same block and need to
      allocate
    - template based backing file is common (esp. in cloud)
    - perf data suggests that data/table format dictates performance ceiling
  - barriers off on underlying fs, cache=writethrough
  - raw backing file (sparse) grows with basic tools like cp
  - suggestion: qed == qcow2 v3
    - wouldn't support encryption and compression (Kevin won't do this)

usb-ccid
- concern about external library implementation
  - hard to add device features, enhancements, live migration protocol changes
- external library
- will resend patch to 

vcpu hard limits
- will continue discussion on list

0.14 (release date, bug day, -rc planning, etc)
- aiming for dec 15th
- will send note out after call with release schedule

0.13.x
- will connect with jforbes regarding -stable maintainance

gPXE vs. iPXE
- ipxe is new fork
- ipxe looking more active (including original gpxe developers)
- which is a better choice?
  - iPXE more active, gPXE stalled
  - some concern about where the community sits (gPXE has irc, bug
    reports, etc)
  - some concern about boot delay with iPXE
- qemu not updating roms that frequently, next time we need to update,
  can evaluate
- syslinux still using gPXE