01:26 <d1b2> <johnsel> They should be sending me a mso8k tomorrow-ish, if all goes to plan I can try to set up a more direct line of communication for things like this

01:37 <azonenberg> Nice

10:55 <_whitenotifier-6> [scopehal-apps] vincentbaeten opened issue #597: ngscopeclient: Black screen and unresponsive when starting on Ubuntu 22.04 - https://github.com/glscopeclient/scopehal-apps/issues/597

11:04 <_whitenotifier-6> [scopehal-apps] vincentbaeten commented on issue #597: ngscopeclient: Black screen and unresponsive when starting on Ubuntu 22.04 - https://github.com/glscopeclient/scopehal-apps/issues/597#issuecomment-1611203073

11:27 <_whitenotifier-6> [scopehal-apps] bvernoux commented on issue #597: ngscopeclient: Black screen and unresponsive when starting on Ubuntu 22.04 - https://github.com/glscopeclient/scopehal-apps/issues/597#issuecomment-1611232075

11:55 <_whitenotifier-6> [scopehal-apps] bvernoux edited a comment on issue #597: ngscopeclient: Black screen and unresponsive when starting on Ubuntu 22.04 - https://github.com/glscopeclient/scopehal-apps/issues/597#issuecomment-1611232075

14:54 <_whitenotifier-6> [scopehal-apps] vincentbaeten commented on issue #597: ngscopeclient: Black screen and unresponsive when starting on Ubuntu 22.04 - https://github.com/glscopeclient/scopehal-apps/issues/597#issuecomment-1611597232

22:46 <azonenberg> So i'm starting to think about writing a multithreaded CSV parser filter lol

22:46 <azonenberg> (in addition to optimizing the processing itself)

22:47 <azonenberg> basic idea is, chunk the file into N blocks (which may or may not be aligned to a newline)

22:47 <azonenberg> once you start a block, if you're not the first one discard any data until the first newline

22:47 <azonenberg> then parse the blocks in parallel and concatenate after they all finish

22:48 <azonenberg> but more importantly i want to mmap the file and use in-memory parsing rather than a bazillion tiny syscalls

22:49 <azonenberg> i think i can probably speed CSV loading by an oom or more

22:49 <whitequark> interestingly IIRC ripgrep found it that mmap doesn't actually speed things up

22:49 <whitequark> if you're reading everything just once

22:49 <azonenberg> whitequark: so in my case i'm in a loop doing fscanf's of single numbers

22:50 <azonenberg> i figure if i do one syscall vs millions, i'll save a lot of overhead

22:50 <azonenberg> also probably replacing fscanf with std::stof or something so it doesnt have to parse the format string for every data element

22:51 <whitequark> oh, nevermind, I have forgotten some details that are crucial here

22:51 <whitequark> namely, ripgrep searches many files, which means there is a large fixed mmap overhead per file

22:51 <whitequark> and that's not your case

22:51 <azonenberg> ah interesting

22:51 <azonenberg> yeah my use case here is loading a ~6.5 GB CSV file in a tractable amount of time

22:52 <whitequark> it uses mmap() when you're grepping a few files, and read() when you're grepping many

22:54 <azonenberg> anyway https://github.com/glscopeclient/scopehal/blob/master/scopeprotocols/CSVImportFilter.cpp#L59

22:54 <azonenberg> i'm certain this can be made a lot faster :p

22:57 <whitequark> yea for sure

23:09 <azonenberg> whitequark: also btw i forget if i mentioned but we fixed a shader bug causing GPU hangs a month or so ago, not sure if you've tried a recent ngscopeclient build

23:14 <whitequark> ah thank you, I think that was a friend who was trying it

23:14 <whitequark> I'll pass it alon

23:14 <whitequark> * I'll pass it along

23:14 <azonenberg> there are still known issues on amd integrated cards

23:14 <azonenberg> but so far none of the folks who actually work on the rendering have access to such a system to test

23:15 <azonenberg> basically the only people doing shader work are me (who has a bunch of discrete nvidia systems as well as a laptop with intel igpu + nvidia optimus) and lain (m1 laptop)

23:56 <_whitenotifier-6> [scopehal] 602p opened pull request #780: Fix memory leak in Filter::FindPeaks - https://github.com/glscopeclient/scopehal/pull/780