parallel

parallel copied to clipboard

Lately I'm getting this error when using amphp/parallel. When I check the previous exception it is

Amp\Parallel\Context\ContextException: Starting the process timed out.

Any idea what could be wrong here and how to fix it?

I tried to wrap the yield enqueue($task); call in a loop, catching the exception and retry on failure. With that I'm getting this:

User Warning: Worker in pool crashed with exception on shutdown: User Warning: Worker in pool exited unexpectedly with code -1

I tried with both uv and native driver, same result.

The issue disappeared when I removed xdebug. :thinking:

It appears that you're starting a worker from within another worker, is that the case?

How many workers total are you spawning?

Issue can be solved by modifying Amp\Parallel\Context\Internal\ProcessHub::PROCESS_START_TIMEOUT. It would be cool to have this configurable instead of hardcoded.

EDIT: I'm using grumphp and it's spawning multiple xdebug instances. After increasing said constant the issue went away.

It appears that you're starting a worker from within another worker, is that the case?

No. Worker was started from the main loop process.

How many workers total are you spawning?

The error appeared with the first worker already.

Issue can be solved by modifying Amp\Parallel\Context\Internal\ProcessHub::PROCESS_START_TIMEOUT. It would be cool to have this configurable instead of hardcoded.

EDIT: I'm using grumphp and it's spawning multiple xdebug instances. After increasing said constant the issue went away.

How far did you increase it? I remember trying that as well to no avail.

@enumag I just added zero at the end.

Yeah, I tried even higher to no avail. It's simply not working for me with xdebug active.

Hi, I have this problem too. I have no xdebug install, and i try to increase PROCESS_START_TIMEOUT with no success. I just try to execute the code on this link https://amphp.org/parallel/ My environnement : centos 7 apache 2.4.6 php 7.2

the error :

<status>500</status> <error>Amp\Parallel\Context\ContextException</error> <message>Starting the process failed</message> <file>.../vendor/amphp/parallel/lib/Context/Process.php</file> <line>202</line>

<trace> 0 [internal function]: Amp\Parallel\Context\Process->Amp\Parallel\Context{closure}() 1 .../vendor/amphp/amp/lib/Coroutine.php(115): Generator->throw(Object(Amp\Parallel\Context\ContextException)) 2 .../vendor/amphp/amp/lib/Failure.php(33): Amp\Coroutine->Amp{closure}(Object(Amp\Parallel\Context\ContextException), NULL) 3 .../vendor/amphp/amp/lib/Internal/Placeholder.php(143): Amp\Failure->onResolve(Object(Closure)) 4 .../vendor/amphp/amp/lib/Internal/Placeholder.php(177): Amp\Coroutine->resolve(Object(Amp\Failure)) 5 .../vendor/amphp/amp/lib/Coroutine.php(137): Amp\Coroutine->fail(Object(Amp\Parallel\Context\ContextException)) 6 .../vendor/amphp/amp/lib/Failure.php(33): Amp\Coroutine->Amp{closure}(Object(Amp\TimeoutException), NULL) 7 .../vendor/amphp/amp/lib/Internal/Placeholder.php(143): Amp\Failure->onResolve(Object(Closure)) 8 .../vendor/amphp/amp/lib/Internal/Placeholder.php(177): class@anonymous->resolve(Object(Amp\Failure)) 9 .../vendor/amphp/amp/lib/Deferred.php(65): class@anonymous->fail(Object(Amp\TimeoutException)) 10 .../vendor/amphp/amp/lib/functions.php(275): Amp\Deferred->fail(Object(Amp\TimeoutException)) 11 .../vendor/amphp/amp/lib/Loop/NativeDriver.php(111): Amp\Promise{closure}('r', NULL) 12 .../vendor/amphp/amp/lib/Loop/Driver.php(138): Amp\Loop\NativeDriver->dispatch(true) 13 .../vendor/amphp/amp/lib/Loop/Driver.php(72): Amp\Loop\Driver->tick() 14 .../vendor/amphp/amp/lib/Loop.php(95): Amp\Loop\Driver->run() 15 .../vendor/amphp/amp/lib/functions.php(229): Amp\Loop::run(Object(Closure)) 16 .../Controller/Admin.php(65): Amp\Promise\wait(Object(Amp\Internal\PrivatePromise)) 17 [internal function]: Api\Controller\Admin->test() </trace>

Thank for your help

Closing this issue, since this has been completely refactored in v2 to allow full customization of context IPC.