Re: Using a new perf tool against an older kernel
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On 6/23/11 7:22 AM, David Ahern wrote:
I have not seen issues like this using newer perf userspace against older kernels. For example, my laptop was running Fedora 14 (2.6.35) and now Fedora 15 (18.104.22.168) and I typically use latest perf builds (e.g., testing patches).
I narrowed it down to PERF_SAMPLE_RAW: perf record -ag -- sleep 1 is fine, but: perf record -agR -- sleep 1fails for me most of the time. The reason I needed to use the -R in the first place is that "perf script" fails on older kernels with:
Samples do not contain timestamps.With the newer perf, I don't get errors, but the timestamp field is invalid. So I need to use the -R flag to get valid timestamps + stacktraces out of "perf script".
-Arun -- To unsubscribe from this list: send the line "unsubscribe linux-perf-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html