To avoid deadlock scenarios where an application runs N isolates on a
thread pool with T threads (T < N) where all scheduled T isolates will
do FFI call and block. That prevents any other isolates from executing.
To avoid such a scenario we add support for the isolate-group specific
thread pool to dynamically increase the maximum size if a worker is
running a isolate mutator thread, which calls to C which exits the
isolate.
=> While such an isolate is descheduled but still occupies a thread
pool worker we temporarily incrase the maximum size of the thread pool.
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: Id61c39b06766da11f76d607ac7cbe8a8e623f250
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/148120
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Our TLAB sizes and maximum new space size constrain the number of
parallel mutator threads we can have. Having too many mutator threads
would cause constant races between threads to acquire TLABs.
In reality we should constrain the number of threads to be at most the
number of cores, since at most that many threads can run in parallel
(i.e. at the same time).
This CL extends the TreadPool implementation to be constrained by a
maximum size. Furthermore it makes each isolate group's have it's own
pool with constrained size and schedule all group member
mutator / message handler tasks on that pool.
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: I095c749adad827ab892f33713a32be594d7606d1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/145382
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
i.e. #ifndef VM_WHATEVER -> #ifndef RUNTIME_VM_WHATEVER
This lets us remove a hack from the PRESUBMIT.py script that existed
for reasons that are no longer valid, and sets us up to add some
presubmit checks for the GN build.
R=asiva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/2450713004 .
Also:
- Reaps exited threads in the thread pool before putting
a thread on the idle list so that a new arriving task
isn't blocked on a supposedly idle thread in the middle
of a join.
- Stops trying to join eventhandler threads on
Windows. Now that we're using the correct exit() call,
we probably don't have to worry about exit code pollution,
so joining the threads is unnecessary.
related #26400R=asiva@google.com, iposva@google.com
Review URL: https://codereview.chromium.org/1978153002 .
. Disables isolate spawning during Dart_Cleanup.
. Adds a static call Isolate::KillAllIsolates, which sends the
OOB Kill message to all isolates when called from
Dart_Cleanup.
. Modifies thread pool shutdown to block until all threads have
exited.
. Fixes tests.
BUG=
R=turnidge@google.com
Review URL: https://codereview.chromium.org//1177153005 .
Martin Kustermann