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| author | Ulf Hermann <ulf.hermann@qt.io> | 2018-06-05 13:38:29 +0200 |
|---|---|---|
| committer | Ulf Hermann <ulf.hermann@qt.io> | 2018-06-05 11:41:53 +0000 |
| commit | 8798990fb1fad04dca8337479e22d17c1fcbfebd (patch) | |
| tree | 6c5b19c28a68d785b74bbec44e9ccbb26037c280 /doc | |
| parent | 5585d97522d34387a5a521ca6bbf59e7ad3488c6 (diff) | |
Doc: Add troubleshooting entry for globally disabled perf events
Change-Id: Ia37b26cc83566b1ae802471c17ef8d309a5d2fa1
Task-number: QTCREATORBUG-20154
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/src/analyze/cpu-usage-analyzer.qdoc | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/doc/src/analyze/cpu-usage-analyzer.qdoc b/doc/src/analyze/cpu-usage-analyzer.qdoc index a43d8ac1dc..3a6019295d 100644 --- a/doc/src/analyze/cpu-usage-analyzer.qdoc +++ b/doc/src/analyze/cpu-usage-analyzer.qdoc @@ -405,6 +405,13 @@ The CPU Usage Analyzer might fail to record data for the following reasons: \list 1 + \li Perf events may be globally disabled on your system. The + preconfigured Boot to Qt images come with perf events enabled. For + a custom configuration you need to make sure that the file + \c {/proc/sys/kernel/perf_event_paranoid} contains a value smaller + than \c {2}. For maximum flexibility in recording traces you can + set the value to \c {-1}. This allows any user to record any kind + of trace, even using raw kernel trace points. \li The connection between the target device and the host may not be fast enough to transfer the data produced by Perf. Try modifying the values of the \uicontrol {Stack snapshot size} or |