This provides 2 things:
1. perf integration with the bench/test runners - This is a bit tricky
with perf as it doesn't have its own way to combine perf measurements
across multiple processes. perf.py works around this by writing
everything to a zip file, using flock to synchronize. As a plus, free
compression!
2. Parsing and presentation of perf results in a format consistent with
the other CSV-based tools. This actually ran into a surprising number of
issues:
- We need to process raw events to get the information we want, this
ends up being a lot of data (~16MiB at 100Hz uncompressed), so we
paralellize the parsing of each decompressed perf file.
- perf reports raw addresses post-ASLR. It does provide sym+off which
is very useful, but to find the source of static functions we need to
reverse the ASLR by finding the delta the produces the best
symbol<->addr matches.
- This isn't related to perf, but decoding dwarf line-numbers is
really complicated. You basically need to write a tiny VM.
This also turns on perf measurement by default for the bench-runner, but at a
low frequency (100 Hz). This can be decreased or removed in the future
if it causes any slowdown.
- Changed multi-field flags to action=append instead of comma-separated.
- Dropped short-names for geometries/powerlosses
- Renamed -Pexponential -> -Plog
- Allowed omitting the 0 for -W0/-H0/-n0 and made -j0 consistent
- Better handling of --xlim/--ylim
These are really just different flavors of test.py and test_runner.c
without support for power-loss testing, but with support for measuring
the cumulative number of bytes read, programmed, and erased.
Note that the existing define parameterization should work perfectly
fine for running benchmarks across various dimensions:
./scripts/bench.py \
runners/bench_runner \
bench_file_read \
-gnor \
-DSIZE='range(0,131072,1024)'
Also added a couple basic benchmarks as a starting point.
Christopher Haster