[27:05][Consider speeding up the hierarchy traversal code in RayCast()][:lighting :performance :research]
[29:54][Launch VTune][:run]
[30:59][Set up to write our :lighting data out to file][:research]
[33:50][Make BuildSpatialPartitionForLighting() write out the :lighting boxes to file, introducing DEBUGDumpData() and a Dump platform_file_type][:"file io"]
[46:57][Traverse the world out to the dungeon with a view to triggering a debug dump of the :lighting boxes][:"file io" :lighting :run]
[1:20:22][Make TestRayCast() set up the :sampling sphere and cast many rays][:lighting]
[1:23:19][:Run hhlightprof, casting all its rays][:lighting]
[1:23:26][Prepare to cast enough rays to last a minimum of 10 seconds][:lighting :research]
[1:25:15][Make TestRayCast() multiply the rays cast by 256][:lighting]
[1:25:25][:Run hhlightprof for just over 10 seconds, without completing][:lighting]
[1:25:36][Decrease the ray multiplier from 256 to 32 in TestRayCast()][:lighting]
[1:25:45][:Run hhlightprof for just almost 10 seconds, without completing][:lighting]
[1:25:54][Decrease the ray multiplier from 32 to 8 in TestRayCast()][:lighting]
[1:26:02][:Run hhlightprof for 9 seconds, to completion][:lighting]
[1:26:12][Decrease the ray multiplier from 8 to 4 in TestRayCast()][:lighting]
[1:26:20][:Run hhlightprof for 5 seconds, to completion][:lighting]
[1:26:25][Prepare to time our ray caster in VTune][:lighting :speech]
[1:28:12][Create a project in VTune for hhlightprof][:admin :lighting]
[1:28:49][A few words on the sheer plethora of performance counters][:speech :profiling]
[1:30:44][Set up our project for hhlightprof][:admin :lighting]
[1:34:03][:Run hhlightprof in VTune][:lighting :profiling]
[1:36:59][:Run a -O2 build of hhlightprof in VTune][:lighting :profiling]
[1:37:11][Increase the ray multiplier from 8 to 32 in TestRayCast()][:lighting]
[1:37:28][:Run hhlightprof for under 1 second, to completion][:lighting]
[1:37:30][Increase the ray multiplier from 32 to 256 in TestRayCast()][:lighting]
[1:37:39][:Run hhlightprof for 5 seconds, to completion][:lighting]
[1:37:46][:Run hhlightprof in VTune][:lighting :profiling]
[1:39:41][Check the Hotspots of hhlightprof in VTune][:lighting :run :profiling]
[1:41:45][Microarchitecture Exploration in VTune][:run :profiling]
[1:43:15][:Run a Microarchitecture Exploration of hhlightprof in VTune][:lighting :profiling]
[1:54:00][:Run a :Memory Access analysis of hhlightprof in VTune][:lighting :profiling]
[1:55:09][Reflect on our isolated ray caster][:lighting :speech]
[1:55:41][Q&A][:speech]
[1:56:23][@yurasniper][Q: Might be a good idea to explain the difference between sampling and instrumentation profilers and how they work on some basic level, and why sampling :profiling is not great idea, despite most people believing and saying that it is very good]
[1:58:39][@lucid_frost][Q: VTune organizes those metrics by something called the "top-down performance analysis methodology". There is a pretty detailed paper that introduced this that would likely help]
[1:58:49][@dragoonx6][Q: Have you ever tried using clang-cl? It's a drop-in MSVC compatible compiler that has much better codegen than MSVC CL. It's compatible with link.exe, but even lld-link will give you usable PDBs. When I used it in my ray tracer, it ended up being 15 times faster than with regular MSVC CL]
[2:01:00][@euphius][Q: Games like CS:GO go up to 300fps. Are they pretty good optimized? Seems like getting [~hero Handmade Hero] to that FPS would be hard?]
[2:01:43][@robgeel][Q: I think you never use the sphere sampling direction in hhlightprof, also when dumping boxes, you write out Solution->BoxCount * sizeof(Solution->Boxes), the sizeof takes the size of a pointer instead of a lighting_box]
[2:01:47][Fix the SampleDirB setting in TestRayCast()][:lighting]
[2:02:04][@lobsang2][Q: What's the status of meowhash? Will it be reaching a new version soon?][:hashing]
[2:02:51][@jim0_o][Q: Have you tried debugging why the stream loses so many frames when you move the character around?]
[2:03:44][@kniffel5][Q: What should meowhash (not) be used for?[ref
[2:07:27][@desu_used][Q: Are you sure the hash is "secure"? People have previously pointed out some issues with meowhash, if I recall correctly, generating collisions[ref
[2:10:03][@brian_nevec][Q: What do you use meowhash for?][:hashing]
[2:10:14][@temdisponivel][Q: Would [~hero Handmade Hero] run on a 32-bit system as it is now, or would it need porting?]
[2:10:22][@dragoonx6][Even for security?][:hashing]
[2:10:58][@vtlmks][Q: Not using the SampleDir?][:lighting]
[2:11:01][Fix TestRayCast() to set (and use) RayD][:lighting]
[2:11:22][@kniffel5][Q: Is meowhash cross platform? For ARM, PowerPC, etc?]
[2:12:29][@mindmark42][Q: Any reason we're not using the checkerboard rendering?][:lighting]
[2:12:54][Begin to wind down the stream, with a plug of the upcoming [@naysayer88 Jon] and [@nothings Sean] talk[ref
author="Jonathan Blow"
publisher=Twitter
title="Tomorrow at 3pm Pacific time I'll be streaming another in-depth programming conversation, this time with Sean Barrett (@nothings). We'll start with the topic of making compilers go fast, but who knows where we'll end up. I will post the link when it happens."
