03:48 mareko: only 1 powerpoint? unbelivable
07:15 MrCooper: there's a Silent Bob joke in there somewhere, having trouble finding it though
10:32 MTCoster: I've just applied a series to drm-misc-next, but I need the first two patches to also get picked into -fixes. Can I just do that myself or should I be asking someone?
12:47 pinchartl: MTCoster: generally speaking, patches should never be merged into multiple branches as separate commits
17:44 alyssa: has anyone benchmarked _mesa_hash_table against other hash-table impls?
17:45 alyssa: it's consistently showing up in flame graphs but I'm.. unsure if hash-tables are intrinsically this slow or we're doing something wrong
17:45 zmike: I've found ht/set to be extremely slow too
17:47 mareko: it should be O(1) if there are no collisions
17:47 alyssa: unfotunately, 1 billion is O(1)
17:47 zmike: it's basically unusable in hotpaths
17:49 mareko: what you probably mean is that 1+ million lookups/s is slow, though even a dumb array may be too slow in that case
17:49 zmike: I've had to switch to sparse array in a number of cases because set/array was unusably slow
17:49 mareko: at that point the optimization goal is to minimize x86 instructions, jumps, and L1 cache misses
17:50 alyssa: I mean that the constant factor on mesa_hash_table is enormous and I'm not sure whether the constant factor on competing impls is noticeably smaller
17:55 alyssa: zmike: is util/sparse_array noticeably better than hash_table_u64..?
17:55 alyssa: (I don't really know how it works, only that it has a bunch of atomics that I don't care for.)
17:55 mareko: I haven't found sparse_array to be better
17:56 zmike: alyssa: yes extremely
17:56 zmike: I cut like 2ms off frametime by switching
17:58 mareko: I don't see zink using it
17:58 zmike: this wasn't in zink
17:59 zmike: but zink bottlenecks on hashtable/set usage so it's on my list to evaluate
17:59 mareko: it must be a secret project then
18:00 zmike: it is
18:00 zmike: I regrettably cannot say more about it at this time
18:00 mareko: zink2
18:01 zmike: would almost certainly be easier and saner