[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] Consistency of iotests 093 and 136
From: |
Alberto Garcia |
Subject: |
Re: [Qemu-devel] Consistency of iotests 093 and 136 |
Date: |
Mon, 28 Jan 2019 16:18:38 +0100 |
User-agent: |
Notmuch/0.18.2 (http://notmuchmail.org) Emacs/24.4.1 (i586-pc-linux-gnu) |
On Thu 24 Jan 2019 07:07:47 PM CET, Eric Blake wrote:
>>>> 093 and 136 seem really flaky to me. I can reproduce that by
>>>> running:
>>>
>>> That's interesting, I can make 093 fail quite easily now (I haven't
>>> tested the other one yet), but I don't think this happened
>>> earlier. I'll try to figure out what's going on.
>>
>> I bisected this and it seems that 093 started to fail after this:
>>
>> 8258292e monitor: Remove "x-oob", offer capability "oob" unconditionally
>>
>> I'm not familiar with that option so I need to investigate.
>
> We've got several tests failing after making x-oob unconditional; here's
> another thread:
>
> https://lists.gnu.org/archive/html/qemu-devel/2019-01/msg05587.html
>
> Could it be that the test was using some sort of QMP command as an
> attempt to synchronize state, but the OOB handling is now making it not
> a reliable sync point?
093 submits several I/O requests using aio_read and aio_write with
hmp_qemu_io(), then advances the clock using clock_step and finally
calls query-blockstats to see how much of the I/O has been completed
(it's an I/O throttling test).
The expectation is that by the time query-blockstats is called all
submitted I/O requests have been processed (up to the amount allowed by
the throttling limits).
Are the QMP (hmp_qemu_io, query-blockstats) and qtest (clock_step)
sockets maybe running in different threads?
Berto