Re: [PATCH 2/2] perf record: Replace 'overwrite' by 'flightrecorder' for better naming

From: Wangnan (F)
Date: Wed Nov 01 2017 - 06:17:54 EST




On 2017/11/1 18:03, Namhyung Kim wrote:
On Wed, Nov 01, 2017 at 05:53:27AM +0000, Wang Nan wrote:
The meaning of perf record's "overwrite" option and many "overwrite" in
source code are not clear. In perf's code, the 'overwrite' has 2 meanings:
1. Make ringbuffer readonly (perf_evlist__mmap_ex's argument).
2. Set evsel's "backward" attribute (in apply_config_terms).

perf record doesn't use meaning 1 at all, but have a overwrite option, its
real meaning is setting backward.

This patch separates these two concepts, introduce 'flightrecorder' mode
which is what we really want. It combines these 2 concept together, wraps
them into a record mode. In flight recorder mode, perf only dumps data before
something happen.
I'm ok with the it but removing old name looks not good. How about
keeping them for a while (as deprecated)?.

Is there a way to hide '--overwrite' from 'perf record --help' and print something
when user really use it?

And 'flightrecorder' seems too long. Maybe you can use an acronym
like FDR or fdr-mode?

fdr-mode is a good name.

Thank you.