I think this is good stuff. I'd gladly take it just for the shader-db improvement.
Marek On Wed, Feb 8, 2017 at 11:35 PM, Thomas Helland <thomashellan...@gmail.com> wrote: > 2017-02-08 22:07 GMT+01:00 Thomas Helland <thomashellan...@gmail.com>: >> 2017-02-08 21:35 GMT+01:00 Thomas Helland <thomashellan...@gmail.com>: >>> I was cleaning up my local git repo, and came across this series. >>> Last time it was discussed was all the way back in April 2015. >>> Things looked pretty good back then, but we where seeing a smaller >>> regression in CPU-bound scenarios as Eric found with forcing software >>> rendering while running Minecraft. >>> >>> I figured I'd do a retest of the series to see how it fares today. >>> Using perf on shader-db I see: >>> hash_table_search being cut from 3.88% down to 1.83%. >>> _mesa_hash_data being cut from 1.47% down to 1.25% >>> _mesa_hash_table_rehash going from 0.23% up to 1.16% >>> hash_table_insert being cut from 2.26% down to 0.33% >>> >> >> This stats are wrong. I recompiled stuff, so the symbols got >> mangled in the libraries. So here is the correct data (after increasing >> the initial size of the set and hash table to 8, so not perfectly >> comparable): >> hash_table_search: 3.88% -> 1.84% >> hash_table_insert: 2.26% -> 1.16% >> _mesa_hash_data is unchanged (which is kinda obvious). >> set_add: 0.70% -> 0.35% >> set_search: 0.59% -> 0.27% >> >>> This yields an approximate 10% reduction in shader-db runtime. >>> >>> The increase in the rehash function is a bit peculiar. >>> I'll look into increasing the table one more step, as a four entry >>> hash table seems a bit on the low side. I'll also work on getting >>> some more reliable numbers from a real world application, along >>> with some more runs of shader-db to get better statistical certainty. >>> I'll pull out my i3-6100 / RX460 combo and give this a spin >>> with Borderlands 2 I think, as Marek's threaded GL work suggests >>> this is a title with heavy CPU bottlenecking. >>> > > Using this hardware I ran the Metro LL Redux benchmark mode > through phoronix-test-suite as a quick test. Average fps improved > from 43,97 to 45.23. So not insane, but a decent gain of 2-3%. > I'll come back with some more numbers from in-game play of > some other games in my possession. Likely CS:GO, portal, > TF2, dota2, borderlands 2, or some other games I have. > >>> As a side note, Robin Hood hashing was mentioned in the thread from >>> back in April 2015. I actually have an implementation of that, but >>> I'm still working out an issue that our make-check tests doesn't >>> catch that causes corruption in the table when runing shader-db. >>> I'm not to sure about it's effect though, as it sacrifices insert >>> speed for lookup speed, but one never knows until one tests. >>> >>> Let me know if this is something I should persue. If not I'll >>> mark this series as "junk" in my git repo, and get on with the cleaning. >>> >>> Thomas Helland (4): >>> util/tests: Expand collision test for hash table >>> util: Change hash_table to use quadratic probing >>> util: Change util/set to use quadratic probing >>> util: Use set_foreach instead of rolling our own >>> >>> src/util/hash_table.c | 102 +++++++++-------------------- >>> src/util/hash_table.h | 3 +- >>> src/util/set.c | 118 >>> ++++++++++++---------------------- >>> src/util/set.h | 3 +- >>> src/util/tests/hash_table/collision.c | 14 ++++ >>> 5 files changed, 89 insertions(+), 151 deletions(-) >>> >>> -- >>> 2.11.1 >>> > _______________________________________________ > mesa-dev mailing list > mesa-dev@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/mesa-dev _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
