Re: [Qemu-devel] How to speed up the CPU logging?

[Blue Swirl]

On Sat, Jun 9, 2012 at 3:07 PM, Yue Chen <address@hidden> wrote:
> Thanks for replying. Do you know any easy way to do that?

See for example commit 870be6ad57d38dd630c5d5ac7e01fc5d8b784485.

Please don't top post.

>
>
> On Sat, Jun 9, 2012 at 11:02 AM, Blue Swirl <address@hidden> wrote:
>>
>> On Sat, Jun 9, 2012 at 2:37 PM, Yue Chen <address@hidden> wrote:
>> > Hi, Guy,
>> >
>> > When I use "log cpu" or "log exec" in the system "-monitor stdio" mode,
>> > it's
>> > extremely slow(lose my mouse/keyboard control). I used a buffer instead
>> > of
>> > directly writing log to disk, but even slower. When I give a large
>> > memory
>> > ("-m 4G") to VM, or set the process priority(chrt -f 99) of QEMU,  the
>> > situation is the same. Any approach to speed up logging? (let me be able
>> > to
>> > control the VM when logging.) Thanks.
>>
>> The performance is slow because logging is text based and therefore
>> there is a lot of processing and I/O.
>>
>> Log users should be converted to trace points which use binary data,
>> that would be much faster and more efficient.
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>