xperf.exe -realtime

NTDEV
1

Hi,

? I have a box with 12 cpus, plenty of ram and need to find out a bottleneck on an mt program. I would like to use xperf -realtime to get as many samples as possible for a short period.

? This is the error displayed on a Win7 box:
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -on Latency -stackwalk Profile -realtime
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -d c:\trace.etl

xperf: error: Merge ETL: The specified path is invalid. (0xa1).

? How do I get realtime samples?

Regards,
? Calin

2

Hello,
There are quite a few posts on the web describing how to profile CPU usage using xperf. For example:

http://blogs.msdn.com/b/pigscanfly/archive/2008/03/02/using-the-windows-sample-profiler-with-xperf.aspx

The command I would typically use for CPU sampling is:
Xperf -on PROC_THREAD+LOADER+PROFILE -stackwalk profile
REM Run your scenario
Xperf -d trace.etl

Thanks,
Alex

From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of Calin Iaru
Sent: Thursday, May 24, 2012 11:44 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] xperf.exe -realtime

Hi,

I have a box with 12 cpus, plenty of ram and need to find out a bottleneck on an mt program. I would like to use xperf -realtime to get as many samples as possible for a short period.

This is the error displayed on a Win7 box:
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -on Latency -stackwalk Profile -realtime
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -d c:\trace.etl

xperf: error: Merge ETL: The specified path is invalid. (0xa1).

How do I get realtime samples?

Regards,
Calin

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3

Alex,

I have used xperf in the past. The -realtime switch is not used in the examples.

The idea is to have -realtime take samples around the time the perf is low and then pinpoint the cause. A few samples and traces don’t hit that curve.

Calin

From: Alex Bendetov
To: Windows System Software Devs Interest List
Sent: Friday, May 25, 2012 11:14 PM
Subject: RE: [ntdev] xperf.exe -realtime

Hello,
There are quite a few posts on the web describing how to profile CPU usage using xperf. For example:

http://blogs.msdn.com/b/pigscanfly/archive/2008/03/02/using-the-windows-sample-profiler-with-xperf.aspx

The command I would typically use for CPU sampling is:
Xperf –on PROC_THREAD+LOADER+PROFILE –stackwalk profile
REM Run your scenario
Xperf –d trace.etl

Thanks,
Alex


From:xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of Calin Iaru
Sent: Thursday, May 24, 2012 11:44 PM
To: Windows System Software Devs Interest List
Subject: [ntdev] xperf.exe -realtime

Hi,

I have a box with 12 cpus, plenty of ram and need to find out a bottleneck on an mt program. I would like to use xperf -realtime to get as many samples as possible for a short period.

This is the error displayed on a Win7 box:
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -on Latency -stackwalk Profile -realtime
PS C:\Users\Administrator> & ‘C:\Program Files\Microsoft Windows Performance Toolkit\xperf.exe’ -d c:\trace.etl

xperf: error: Merge ETL: The specified path is invalid. (0xa1).

How do I get realtime samples?

Regards,
Calin

—
NTDEV is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at http://www.osronline.com/page.cfm?name=ListServer
—
NTDEV is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at http://www.osronline.com/page.cfm?name=ListServer