Re: [Qemu-devel] [RFC PATCH 0/9] Add colo-proxy based on netfilter

[Zhang Chen]

Hi,Dave

On 12/02/2015 12:44 AM, Dr. David Alan Gilbert wrote:
> * Zhang Chen (address@hidden) wrote:
> > 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.
> >
> > You can also get the series from:
> >
> > https://github.com/zhangckid/qemu/tree/colo-proxy-V1
> >
> > Usage:
> >
> > primary:
> > -netdev tap,id=bn0 -device e1000,netdev=bn0
> > -object colo-proxy,id=f0,netdev=bn0,queue=all,mode=primary,addr=ip:port
> >
> > secondary:
> > -netdev tap,id=bn0 -device e1000,netdev=bn0
> > -object colo-proxy,id=f0,netdev=bn0,queue=all,mode=secondary,addr=ip:port
> If we have more than one NIC on the guest, do you intend to allow
> multiple colo-proxy's ?

Yes,we support.Colo-proxy based on netfilter, same to filter-buffer, 
proxy attach your netdev.
but we haven't test it

> Having read through the series, it looks like the main missing piece
> is the work to synchronise sequence numbers.

Yes, we will support it in the futrue

> I think also you'll need to clean out the connection hash when either
> you see both sides have closed the connection or (maybe after some
> time of idleness as well? Otherwise we'd just accumulate dead connections
> overtime).
>
> I'm guessing the buffer filter also has to be created on the command line?
> How does the order of buffers work?
>
> Dave

In colo-proxy we have done buffer filter's work,so we just need startup
colo-proxy.

Thanks for review
zhangchen

> > NOTE:
> > queue must set "all". See enum NetFilterDirection for detail.
> > colo-proxy need queue all packets
> > colo-proxy V1 just a demo of colo proxy,not pass test with colo upstream
> >
> >
> > ## 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.
> >
> >
> > v1:
> >   initial patch.
> >
> >
> >
> > zhangchen (9):
> >    Init colo-proxy object based on netfilter
> >    jhash: add linux kernel jhashtable in qemu
> >    colo-proxy: add colo-proxy framework
> >    colo-proxy: add colo-proxy setup work
> >    net/colo-proxy: add colo packet handler
> >    net/colo-proxy: add packet forward function
> >    net/colo-proxy: add packet enqueue and handle function
> >    net/colo-proxy: enqueue primary and secondary packet
> >    net/colo-proxy: add packet compare and notify checkpoint
> >
> >   include/qemu/jhash.h |  52 ++++
> >   net/Makefile.objs    |   1 +
> >   net/colo-proxy.c     | 745 +++++++++++++++++++++++++++++++++++++++++++++++++++
> >   net/colo-proxy.h     | 124 +++++++++
> >   qemu-options.hx      |   4 +
> >   vl.c                 |   3 +-
> >   6 files changed, 928 insertions(+), 1 deletion(-)
> >   create mode 100644 include/qemu/jhash.h
> >   create mode 100644 net/colo-proxy.c
> >   create mode 100644 net/colo-proxy.h
> >
> > --
> > 1.9.1
> --
> Dr. David Alan Gilbert / address@hidden / Manchester, UK
>
>
> .