* Re: [Qemu-devel] how could I analysis the trace log?
2012-02-12 4:32 [Qemu-devel] how could I analysis the trace log? Wei Yang
@ 2012-02-13 3:24 ` Wei Yang
2012-02-13 3:25 ` 陳韋任
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Wei Yang @ 2012-02-13 3:24 UTC (permalink / raw)
To: qemu-devel
Hi, this kind of trace is not popular?
2012/2/12 Wei Yang <weiyang.kernel@gmail.com>:
> All
>
> I enable the trace function with --enable-trace-backend=simple and I
> create the event file like this
> g_realloc
> g_malloc
>
> Then I start the qemu with following command.
> ./i386-softmmu/qemu-system-i386 -enable-kvm -drive
> file=../../kvm/ubuntu.img -boot dc -m 512 -usb
> -monitor stdio -trace events=qemu_trace_events,file=qemu_trace.log
>
> After some run time, I run the script like:
> ./scripts/simpletrace.py qemu_trace_events_parse qemu_trace.log
>
> The qemu_trace_events_parse is :
> g_realloc(addr)
> g_malloc(addr)
>
> The output looks like:
> g_malloc 1.831 addr=0xb945d1f0
> g_malloc 2.498 addr=0xb945d1f0
> g_realloc 4.715 addr=0x10
> g_realloc 1.520 addr=0xc
> g_realloc 1.505 addr=0xc
>
> The steps I used is correct?
> I just guess the format of input events file of the simpletrace.py.
> For so many available events, how could I specify the format of all
> those events?
>
> --
> Richard Yang
> Help You, Help Me
--
Richard Yang
Help You, Help Me
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [Qemu-devel] how could I analysis the trace log?
2012-02-12 4:32 [Qemu-devel] how could I analysis the trace log? Wei Yang
2012-02-13 3:24 ` Wei Yang
@ 2012-02-13 3:25 ` 陳韋任
2012-02-13 11:22 ` Stefan Hajnoczi
2012-02-13 15:12 ` Andreas Färber
3 siblings, 0 replies; 6+ messages in thread
From: 陳韋任 @ 2012-02-13 3:25 UTC (permalink / raw)
To: Wei Yang; +Cc: qemu-devel
> I just guess the format of input events file of the simpletrace.py.
> For so many available events, how could I specify the format of all
> those events?
http://repo.or.cz/w/qemu/stefanha.git/blob_plain/refs/heads/tracing:/docs/tracing.txt
Reading "Trace events" might be help.
Regards,
chenwj
--
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] how could I analysis the trace log?
2012-02-12 4:32 [Qemu-devel] how could I analysis the trace log? Wei Yang
2012-02-13 3:24 ` Wei Yang
2012-02-13 3:25 ` 陳韋任
@ 2012-02-13 11:22 ` Stefan Hajnoczi
2012-02-13 15:12 ` Andreas Färber
3 siblings, 0 replies; 6+ messages in thread
From: Stefan Hajnoczi @ 2012-02-13 11:22 UTC (permalink / raw)
To: Wei Yang; +Cc: qemu-devel
On Sun, Feb 12, 2012 at 4:32 AM, Wei Yang <weiyang.kernel@gmail.com> wrote:
> After some run time, I run the script like:
> ./scripts/simpletrace.py qemu_trace_events_parse qemu_trace.log
>
> The qemu_trace_events_parse is :
> g_realloc(addr)
> g_malloc(addr)
>
> The output looks like:
> g_malloc 1.831 addr=0xb945d1f0
> g_malloc 2.498 addr=0xb945d1f0
> g_realloc 4.715 addr=0x10
> g_realloc 1.520 addr=0xc
> g_realloc 1.505 addr=0xc
>
> The steps I used is correct?
Yes, that's fine. The output fields are trace event name, delta time
since last event (in microseconds), and arguments printed as hex
numbers.
> I just guess the format of input events file of the simpletrace.py.
> For so many available events, how could I specify the format of all
> those events?
simpletrace.py does not format events in a special way. It simply
prints them all out as hex numbers.
If you want special formatting you should write a custom trace
analysis script. It's pretty easy to do and you can find an example
here:
http://blog.vmsplice.net/2011/03/how-to-write-trace-analysis-scripts-for.html
If you looked at the simpletrace.py source code you may have noticed
that it is actually a Python module. It provides an API so you can
process the trace events that you are interested in.
Stefan
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Qemu-devel] how could I analysis the trace log?
2012-02-12 4:32 [Qemu-devel] how could I analysis the trace log? Wei Yang
` (2 preceding siblings ...)
2012-02-13 11:22 ` Stefan Hajnoczi
@ 2012-02-13 15:12 ` Andreas Färber
2012-02-13 16:31 ` Stefan Hajnoczi
3 siblings, 1 reply; 6+ messages in thread
From: Andreas Färber @ 2012-02-13 15:12 UTC (permalink / raw)
To: Wei Yang; +Cc: Stefan Hajnoczi, qemu-devel
Hi,
Am 12.02.2012 05:32, schrieb Wei Yang:
> I enable the trace function with --enable-trace-backend=simple and I
> create the event file like this
> g_realloc
> g_malloc
>
> Then I start the qemu with following command.
> ./i386-softmmu/qemu-system-i386 -enable-kvm -drive
> file=../../kvm/ubuntu.img -boot dc -m 512 -usb
> -monitor stdio -trace events=qemu_trace_events,file=qemu_trace.log
>
> After some run time, I run the script like:
> ./scripts/simpletrace.py qemu_trace_events_parse qemu_trace.log
>
> The qemu_trace_events_parse is :
> g_realloc(addr)
> g_malloc(addr)
>
> The output looks like:
> g_malloc 1.831 addr=0xb945d1f0
> g_malloc 2.498 addr=0xb945d1f0
> g_realloc 4.715 addr=0x10
> g_realloc 1.520 addr=0xc
> g_realloc 1.505 addr=0xc
>
> The steps I used is correct?
Not quite. IIRC you need to pass in path/to/qemu/trace-events with the
full list of events you were using at the time of tracing (trace file
uses index of event). That file also contains a format string from which
you can infer what the arguments mean.
> I just guess the format of input events file of the simpletrace.py.
> For so many available events, how could I specify the format of all
> those events?
Not knowing Python too well myself, I just wrote a small analysis script
from scratch for my specific task, based on the simpletrace source code.
Andreas
--
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [Qemu-devel] how could I analysis the trace log?
2012-02-13 15:12 ` Andreas Färber
@ 2012-02-13 16:31 ` Stefan Hajnoczi
0 siblings, 0 replies; 6+ messages in thread
From: Stefan Hajnoczi @ 2012-02-13 16:31 UTC (permalink / raw)
To: Andreas Färber; +Cc: Wei Yang, qemu-devel
On Mon, Feb 13, 2012 at 3:12 PM, Andreas Färber <afaerber@suse.de> wrote:
> Hi,
>
> Am 12.02.2012 05:32, schrieb Wei Yang:
>> I enable the trace function with --enable-trace-backend=simple and I
>> create the event file like this
>> g_realloc
>> g_malloc
>>
>> Then I start the qemu with following command.
>> ./i386-softmmu/qemu-system-i386 -enable-kvm -drive
>> file=../../kvm/ubuntu.img -boot dc -m 512 -usb
>> -monitor stdio -trace events=qemu_trace_events,file=qemu_trace.log
>>
>> After some run time, I run the script like:
>> ./scripts/simpletrace.py qemu_trace_events_parse qemu_trace.log
>>
>> The qemu_trace_events_parse is :
>> g_realloc(addr)
>> g_malloc(addr)
>>
>> The output looks like:
>> g_malloc 1.831 addr=0xb945d1f0
>> g_malloc 2.498 addr=0xb945d1f0
>> g_realloc 4.715 addr=0x10
>> g_realloc 1.520 addr=0xc
>> g_realloc 1.505 addr=0xc
>>
>> The steps I used is correct?
>
> Not quite. IIRC you need to pass in path/to/qemu/trace-events with the
> full list of events you were using at the time of tracing (trace file
> uses index of event). That file also contains a format string from which
> you can infer what the arguments mean.
Right:
$ scripts/simpletrace.py trace-events trace-12345
^ permalink raw reply [flat|nested] 6+ messages in thread