Re: [Qemu-discuss] Latest Qemu-COLO Problems

[Zhang, Chen]

Sure, If it is convenient, you can try to debug under your environment and send 
a patch to Qemu community.
I am very happy to review it.

Thanks
Zhang Chen

From: wenzt [mailto:address@hidden
Sent: Wednesday, March 13, 2019 1:49 PM
To: Zhang, Chen <address@hidden>
Cc: 'qemu-discuss' <address@hidden>
Subject: 答复: Latest Qemu-COLO Problems

Your answer make sense to me.
Different network environment may result in that status.
I think more attention should be paid on the compatibility of COLO Proxy.


发件人: Zhang, Chen <address@hidden<mailto:address@hidden>>
发送时间: 2019年3月13日 11:49
收件人: wenzt <address@hidden<mailto:address@hidden>>
抄送: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
主题: RE: Latest Qemu-COLO Problems


From: wenzt [mailto:address@hidden
Sent: Wednesday, March 6, 2019 6:28 PM
To: Zhang, Chen <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: 答复: Latest Qemu-COLO Problems

I have tested Proxy with QMP: "{'execute': 'trace-event-set-state', 
'arguments': {'name': 'colo*', 'enable': true} }"

I got this nothing except this logs on PVM side:
address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
secondary: unsupported packet in
address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
secondary: unsupported packet in
address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
secondary: unsupported packet in
address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
primary: unsupported packet in
address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
secondary: unsupported packet in

My guest OS is Centos 7.5.
I did nothing but boot up the OS.
After that, firing some net IO still get those logs.

I did some debug, maybe some parse error in parse_packet_early(), get the wrong 
ETH_P_protocolName

Hi Zhengtao,

I think your test environment have some net issue, can you get IP in the guest? 
Without COLO guest’s status?
Or you use Jiaoyuwang to test? network switch do some job in ETH level(like 
vlan)?
In my side primary node proxy report like that:

address@hidden:colo_send_message<mailto:address@hidden:colo_send_message> Send 
'checkpoint-request' message

address@hidden:colo_receive_message<mailto:address@hidden:colo_receive_message> 
Receive 'checkpoint-reply' message

{"timestamp": {"seconds": 1552455102, "microseconds": 148903}, "event": "STOP"}

address@hidden:colo_vm_state_change<mailto:address@hidden:colo_vm_state_change> 
Change 'run' => 'stop'

address@hidden:colo_send_message<mailto:address@hidden:colo_send_message> Send 
'vmstate-send' message

address@hidden:colo_send_message<mailto:address@hidden:colo_send_message> Send 
'vmstate-size' message

address@hidden:colo_receive_message<mailto:address@hidden:colo_receive_message> 
Receive 'vmstate-received' message

address@hidden:colo_receive_message<mailto:address@hidden:colo_receive_message> 
Receive 'vmstate-loaded' message

{"timestamp": {"seconds": 1552455102, "microseconds": 277064}, "event": 
"RESUME"}

address@hidden:colo_vm_state_change<mailto:address@hidden:colo_vm_state_change> 
Change 'stop' => 'run'

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
compare udp

address@hidden:colo_compare_ip_info<mailto:address@hidden:colo_compare_ip_info> 
ppkt size = 81, ip_src = 10.239.161.136, ip_dst = 10.248.2.5, spkt size = 81, 
ip_src = 10.239.161.136, ip_dst = 10.248.2.5

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
packet same and release packet

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
compare udp

address@hidden:colo_compare_ip_info<mailto:address@hidden:colo_compare_ip_info> 
ppkt size = 81, ip_src = 10.239.161.136, ip_dst = 10.239.27.228, spkt size = 
81, ip_src = 10.239.161.136, ip_dst = 10.239.27.228

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
packet same and release packet

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
compare udp

address@hidden:colo_compare_ip_info<mailto:address@hidden:colo_compare_ip_info> 
ppkt size = 81, ip_src = 10.239.161.136, ip_dst = 172.17.6.9, spkt size = 81, 
ip_src = 10.239.161.136, ip_dst = 172.17.6.9

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
packet same and release packet

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
compare udp

address@hidden:colo_compare_ip_info<mailto:address@hidden:colo_compare_ip_info> 
ppkt size = 81, ip_src = 10.239.161.136, ip_dst = 10.248.2.5, spkt size = 81, 
ip_src = 10.239.161.136, ip_dst = 10.248.2.5

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
packet same and release packet

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
compare icmp

address@hidden:colo_compare_ip_info<mailto:address@hidden:colo_compare_ip_info> 
ppkt size = 157, ip_src = 10.239.161.136, ip_dst = 172.17.6.9, spkt size = 157, 
ip_src = 10.239.161.136, ip_dst = 172.17.6.9

address@hidden:colo_compare_main<mailto:address@hidden:colo_compare_main> : 
packet same and release packet




Thanks
Zhang Chen


Thanks,
Zhengtao

发件人: Zhang, Chen <address@hidden<mailto:address@hidden>>
发送时间: 2019年3月5日 23:32
收件人: wenzt <address@hidden<mailto:address@hidden>>
抄送: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
主题: RE: Latest Qemu-COLO Problems


From: wenzt [mailto:address@hidden
Sent: Thursday, February 28, 2019 10:00 AM
To: Zhang, Chen <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: 答复: Latest Qemu-COLO Problems

This version: https://github.com/coloft/qemu/tree/colo-v4.1-periodic-mode

This is old version from 3 years ago, please drop it, use qemu upstream codes.

Another question:
What is the relationship between Proxy and Checkpoint ?

When PVM and SVM send different net packet, proxy will send a signal to 
COLO-frame to do a checkpoint.

Do they work together ? I guess we should set checkpoint interval longer like 
20s.

Yes, they work together, at the same time, we have periodic checkpoint 
mechanism, like a timer. You can set the time too.

Does Proxy only works under network workload ? In my test, I feel like Proxy 
not working.

Yes, as wiki said, colo-proxy compare the PVM and SVM packet to decide if do 
checkpoint.
You can enable the COLO debug info to see proxy’s job in primary node like this:
"{'execute': 'trace-event-set-state', 'arguments': {'name': 'colo*', 'enable': 
true} }"


Thanks
Zhang Chen


发件人: Zhang, Chen <address@hidden<mailto:address@hidden>>
发送时间: 2019年2月28日 9:34
收件人: wenzt <address@hidden<mailto:address@hidden>>
抄送: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
主题: RE: Latest Qemu-COLO Problems

Which version?
COLO project always said the PVM and SVM execute in parallel.

Thanks
Zhang Chen

From: wenzt [mailto:address@hidden
Sent: Thursday, February 28, 2019 9:21 AM
To: Zhang, Chen <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: 答复: Latest Qemu-COLO Problems

But in earlier version, I noticed that SVM always inmigration status even doing 
checkpoint.
No operation can be performed on SVM.

Thanks,
Zhengtao

发件人: Zhang, Chen <address@hidden<mailto:address@hidden>>
发送时间: 2019年2月27日 18:45
收件人: wenzt <address@hidden<mailto:address@hidden>>
抄送: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
主题: RE: Latest Qemu-COLO Problems


From: wenzt [mailto:address@hidden
Sent: Wednesday, February 27, 2019 6:04 PM
To: Zhang, Chen <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: 答复: Latest Qemu-COLO Problems

Thanks for help !

I don’t know why we keep switching SVM between Run and Stop ?
Why we don’t keep SVM inmigration status ?

Because we need do checkpoint to sync all status between PVM and SVM.
We can’t guarantee that their status will be the same after a while.

Thanks
Zhang Chen

Thanks,
Zhengtao

发件人: Zhang, Chen <address@hidden<mailto:address@hidden>>
发送时间: 2019年2月26日 18:41
收件人: wenzt <address@hidden<mailto:address@hidden>>
抄送: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
主题: RE: Latest Qemu-COLO Problems

By the way, please read the COLO wiki use this command to trigger failover in 
secondary node:

{ 'execute': 'nbd-server-stop' }
{ "execute": "x-colo-lost-heartbeat" }


Thanks
Zhang Chen

From: Zhang, Chen
Sent: Tuesday, February 26, 2019 2:46 PM
To: 'wenzt' <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: RE: Latest Qemu-COLO Problems

Sorry for slow response.
I have fixed this bug in this series:

https://lists.nongnu.org/archive/html/qemu-devel/2019-02/msg06920.html

Please test it.


Thanks
Zhang Chen

From: wenzt [mailto:address@hidden
Sent: Friday, February 15, 2019 7:54 PM
To: Zhang, Chen <address@hidden<mailto:address@hidden>>
Cc: 'qemu-discuss' <address@hidden<mailto:address@hidden>>
Subject: Latest Qemu-COLO Problems

Hi Zhang，

I have tested COLO with qemu-3.1.0 follow https://wiki.qemu.org/Features/COLO

I got this problems on PVM:
{"timestamp": {"seconds": 1550230616, "microseconds": 644348}, "event": "STOP"}
{"timestamp": {"seconds": 1550230616, "microseconds": 719003}, "event": 
"RESUME"}
{"timestamp": {"seconds": 1550230616, "microseconds": 743554}, "event": "STOP"}
qemu-system-x86_64: Can't receive COLO message: Input/output error
qemu-system-x86_64: Can't receive COLO message: Input/output error
{"timestamp": {"seconds": 1550230618, "microseconds": 257209}, "event": 
"COLO_EXIT", "data": {"mode": "primary", "reason": "error"}}


And on SVM:
{"timestamp": {"seconds": 1550230616, "microseconds": 731544}, "event": "STOP"}
address@hidden:colo_vm_state_change<mailto:address@hidden:colo_vm_state_change> 
Change 'run' => 'stop'
address@hidden:colo_send_message<mailto:address@hidden:colo_send_message> Send 
'checkpoint-reply' message
address@hidden:colo_receive_message<mailto:address@hidden:colo_receive_message> 
Receive 'vmstate-send' message
address@hidden:colo_flush_ram_cache_begin<mailto:address@hidden:colo_flush_ram_cache_begin>
 dirty_pages 18446744073708498780
address@hidden:colo_flush_ram_cache_end<mailto:address@hidden:colo_flush_ram_cache_end>
address@hidden:colo_receive_message<mailto:address@hidden:colo_receive_message> 
Receive 'vmstate-size' message
address@hidden:colo_send_message<mailto:address@hidden:colo_send_message> Send 
'vmstate-received' message
{"timestamp": {"seconds": 1550230616, "microseconds": 837436}, "event": 
"RESUME"}
qemu-system-x86_64: block.c:5062: bdrv_detach_aio_context: Assertion 
`!bs->walking_aio_notifiers' failed.
Aborted (core dumped)