On Friday, 25 June 2021 at 14:44:13 UTC, seany wrote:

With ldc2 this segfaults for me even if std.parallelism is removed
entirely. With DMD and std.parallelism removed it runs to completion.
With DMD and no changes it never seems to finish.

I reckon that there's some other memory error and that the parallelism
is unrelated.

On Friday, 25 June 2021 at 15:16:30 UTC, jfondren wrote:

@safe:

source/AI.d(83,23): Error: cannot take address of local `rData` in `@safe` function `main`
source/analysisEngine.d(560,20): Error: cannot take address of local `rd_flattened` in `@safe` function `add_missingPoints`
source/analysisEngine.d(344,5): Error: can only catch class objects derived from `Exception` in `@safe` code, not `core.exception.RangeError`

And then, about half complaints about @system dlib calls and
complaints about void* <-> rawData[]* casting

The RangeError catch likely does nothing with your compile flags.

Even if you don't intend to use @safe in the end, I'd bet that the
segfaults are due to what it's complaining about.

On Friday, 25 June 2021 at 15:16:30 UTC, jfondren wrote:

Try : (this version)[https://github.com/naturalmechanics/mwp/tree/nested-loops]

The goal is to parallelize : calculate_avgSweepDist_pairwise at line 3836. Notice there we have 6 nested loops. Thank you.

On Friday, 25 June 2021 at 15:50:37 UTC, seany wrote:

Ok, i stopped the buss error and the segfault. It was indeed an index that was written wrong in the flattened version .

No, I dont have the seg fault any more. But I have "error creating thread" - time to time. Not always.

But, even with the taskpool, it is not spreading to multiple cores.

On Friday, 25 June 2021 at 16:37:06 UTC, seany wrote:

PS: this is the error message : "core.thread.threadbase.ThreadError@src/core/thread/threadbase.d(1219): Error creating thread"

On Friday, 25 June 2021 at 16:37:44 UTC, seany wrote:

If i use parallel(...)it runs.

If i use prTaskPool.parallel(..., then in the line : auto prTaskPool = new TaskPool(threadCount); it hits the error. Please help.

On Friday, 25 June 2021 at 19:17:38 UTC, seany wrote:

parallel() reuses a single taskPool that's only established once.

Your code creates two TaskPools per a function invocation and you
call that function in a loop.

stracing your program might again reveal the error you're hitting.

On Friday, 25 June 2021 at 19:30:16 UTC, jfondren wrote:

I have removed one - same problem.
Yes, I do call it in a loop. how can I create a taskpool in a function that itself will be called in a loop?

On Friday, 25 June 2021 at 19:52:23 UTC, seany wrote:

One option is to do as parallel does:
https://github.com/dlang/phobos/blob/master/std/parallelism.d#L3508