Firstly, if you are allocating 1.8Gb you are likely pushing up against browser limits. Are you specifying a MAXIMUM_MEMORY of larger than 2GB?
Secondly, it looks like you are using wasm workers, which are still relatively new. Do you have a version of your code that uses pthreads instead? It might tell is if the issue is related to wasm workers. cheers, sam On Thu, May 25, 2023 at 8:06 AM 'Dieter Weidenbrück' via emscripten-discuss <emscripten-discuss@googlegroups.com> wrote: > The joy was premature, even with pre-allocated heap size segfaults occur. > :( > > Dieter Weidenbrück schrieb am Donnerstag, 25. Mai 2023 um 16:28:37 UTC+2: > >> All, >> I am experiencing segmentation faults when using wasm workers. >> Overview: >> I am working on a project with considerable 3D data sets. The code has >> been stable for a while when running in the main thread alone. Then I >> started using js workers (no shared memory), and again all was well. >> Now I've switched to SharedArrayBuffers and wasm workers, and I keep >> running into random problems. >> I have prepared the code such that I can run with 0 workers up to >> hardware.concurrency workers. All is well with 0 workers, but as soon as I >> use one or more workers, I keep getting segfaults because of invalid >> pointers, access out of bounds and similar. >> >> What happens in main thread and what in the wasm workers: >> I allocate all objects in the main thread when importing the 3D file. >> Then i fire off a function for each object that will do some serious >> calculations of the data, including allocating and disposing of memory. The >> workers allocate approx. 300 to 400 MB in addition to the main thread. All >> this happens in the same sharedArrayBuffer, of course. >> >> Here is what I've tried so far: >> - compiling with SAFE_HEAP=1 >> not a lot of helpful information, >> - compiling with -fsanitize=address >> everything works without problems here! >> - compiling with ASSERTIONS=2 >> gave me this information: >> [image: error.png] >> >> To me it looks like another resize call is executed while other workers >> keep working on the buffer, and then something gets into conflict. >> To test this, I allocated 1.8 GB right after startup in the main thread >> and disposed the mem blocks again just to trigger heap resize. After that >> everything works like a charm. >> >> Is there anything I am doing wrong? >> Sorry for not providing a sample, but there is a lot of code involved, >> and it is not easy to simulate this behavior. Happy to answer questions. >> >> All comments are appreciated. >> Thanks, >> Dieter >> > -- > You received this message because you are subscribed to the Google Groups > "emscripten-discuss" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to emscripten-discuss+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/emscripten-discuss/80d56314-59d8-4332-bb2e-ebe00fe52ea3n%40googlegroups.com > <https://groups.google.com/d/msgid/emscripten-discuss/80d56314-59d8-4332-bb2e-ebe00fe52ea3n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to emscripten-discuss+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/emscripten-discuss/CAL_va28J5-c7A2PmrUStwz1GtBD76djg5sPA76rM%3D%3DE5qe95qw%40mail.gmail.com.
