Re: [PATCH] perf record: Add snapshot mode support for perf's regular events

From: David Ahern
Date: Tue Nov 24 2015 - 11:16:17 EST


On 11/24/15 8:40 AM, Arnaldo Carvalho de Melo wrote:
perf-record without his patch? yes, but with his patch it does:

__cmd_record()
for (;;)
record__mmap_read_all()
record__write()
perf_memory__write()
event = (union perf_event *)(memory->start + memory->head + skip);
if (event->header.type != PERF_RECORD_SAMPLE) {
if (buf_to_file(rec, memory->start, memory->size,
}

I almost thought that I had been fooled by the difficulty to follow his
patch and was forgetting that 'perf record' doesn't processes events,
and hasn't done so for a very good reason: to reduce its impact on the
observed workload, but that ain't so, no?

exactly. And I missed the above. Thanks for pointing that out.
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