On 12/31/2015 10:36 AM, Jason Wang wrote:
On 12/22/2015 06:42 PM, Zhang Chen wrote:
From: zhangchen <zhangchen.f...@cn.fujitsu.com>
Hi,all
This patch add an colo-proxy object, COLO-Proxy is a part of COLO,
based on qemu netfilter and it's a plugin for qemu netfilter. the function
keep Secondary VM connect normal to Primary VM and compare packets
sent by PVM to sent by SVM.if the packet difference,notify COLO do
checkpoint and send all primary packet has queued.
Thanks for the work. I don't object this method but still not convinced
that qemu is the best place for this.
As been raised in the past discussion, it's almost impossible to
cooperate with vhost backends. If we want this to be used in production
environment, need to think of a solution for vhost. There's no such
worry if we decouple this from qemu.
You can also get the series from:
https://github.com/zhangckid/qemu/tree/colo-v2.2-periodic-mode-with-colo-proxyV2
Usage:
primary:
-netdev tap,id=bn0 -device e1000,netdev=bn0
-object colo-proxy,id=f0,netdev=bn0,queue=all,mode=primary,addr=host:port
secondary:
-netdev tap,id=bn0 -device e1000,netdev=bn0
-object colo-proxy,id=f0,netdev=bn0,queue=all,mode=secondary,addr=host:port
Have a quick glance at how secondary mode work. What it does is just
forwarding packets between a nic and a socket, qemu socket backend did
exact the same job. You could even use socket in primary node and let
packet compare module talk to both primary and secondary node.
If we use qemu socket backend , the same netdev will used by qemu socket
and
qemu netfilter. this will against qemu net design. and then, when colo
do failover,
secondary do not have backend to use. that's the real problem.
Thanks
zhangchen
NOTE:
queue must set "all". See enum NetFilterDirection for detail.
colo-proxy need queue all packets
colo-proxy V2 just can compare ip packet
## Background
COLO FT/HA (COarse-grain LOck-stepping Virtual Machines for Non-stop Service)
project is a high availability solution. Both Primary VM (PVM) and Secondary VM
(SVM) run in parallel. They receive the same request from client, and generate
responses in parallel too. If the response packets from PVM and SVM are
identical, they are released immediately. Otherwise, a VM checkpoint (on
demand)is conducted.
Paper:
http://www.socc2013.org/home/program/a3-dong.pdf?attredirects=0
COLO on Xen:
http://wiki.xen.org/wiki/COLO_-_Coarse_Grain_Lock_Stepping
COLO on Qemu/KVM:
http://wiki.qemu.org/Features/COLO
By the needs of capturing response packets from PVM and SVM and finding out
whether they are identical, we introduce a new module to qemu networking
called colo-proxy.
V2:
rebase colo-proxy with qemu-colo-v2.2-periodic-mode
fix dave's comments
fix wency's comments
fix zhanghailiang's comments
v1:
initial patch.
zhangchen (10):
Init colo-proxy object based on netfilter
Jhash: add linux kernel jhashtable in qemu
Colo-proxy: add colo-proxy framework
Colo-proxy: add data structure and jhash func
net/colo-proxy: Add colo interface to use proxy
net/colo-proxy: add socket used by forward func
net/colo-proxy: Add packet enqueue & handle func
net/colo-proxy: Handle packet and connection
net/colo-proxy: Compare pri pkt to sec pkt
net/colo-proxy: Colo-proxy do checkpoint and clear
include/qemu/jhash.h | 61 ++++
net/Makefile.objs | 1 +
net/colo-proxy.c | 939 +++++++++++++++++++++++++++++++++++++++++++++++++++
net/colo-proxy.h | 24 ++
qemu-options.hx | 6 +
trace-events | 8 +
vl.c | 3 +-
7 files changed, 1041 insertions(+), 1 deletion(-)
create mode 100644 include/qemu/jhash.h
create mode 100644 net/colo-proxy.c
create mode 100644 net/colo-proxy.h
.
--
Thanks
zhangchen
