Sometimes when we call ShutdownWithTimeout on a thread pool, the unresponsive
thread that we leak will actually complete before the main thread is done.
In that case, the thread will dereference the thread shutdown context, so
we must intentionally leak it too.
Differential Revision: https://phabricator.services.mozilla.com/D10645
This method is necessary because some threads might be stuck making blocking
calls. This means the thread is not processing any events, and we're unable
to safely terminate it. Our solution here is to leak the stuck threads
instead of waiting for them and potentially causing a shutdown hang.
Differential Revision: https://phabricator.services.mozilla.com/D9601
--HG--
extra : moz-landing-system : lando
Instead of creating a timer and then setting the timer's target, we can
determine the timer's target and pass it in directly when the timer is
created. This reordering of steps is slightly more efficient, since
SetTarget() is both a virtual call and requires locking, both of which
can be skipped if we know the target at timer creation time. If we're
reusing the timer, we also don't need to repeatedly set the timer's
target: we can set the target once at timer creation, and then be done.
We can do this safely here because mTaskCategory doesn't change
throughout the life of the IdleTaskRunner; we make mTaskCategory `const`
to make this more explicit to the reader.
The NS_NewTimer* family of functions, when using a custom event target,
currently go through a path that looks something like:
auto timer = createTimer()
timer->SetTarget(target);
// call the requisite Init* function
return timer;
This setup is inefficient, because SetTarget requires the timer mutex to
be acquired. The mutex acquisition here is completely unnecessary,
because the timer hasn't yet been shared out to the wider world; we can
set the timer target without acquiring the mutex at all because we know
that no sharing is possible at this point.
This patch reworks things somewhat to make that possible.
If class A is derived from class B, then an instance of class A can be
converted to B via a static cast, so a slower QI is not needed.
Differential Revision: https://phabricator.services.mozilla.com/D6861
--HG--
extra : moz-landing-system : lando
This doesn't fix the problem, but at least moves the resulting assertion
closer to the problematic caller, and makes it easier to diagnose.
Differential Revision: https://phabricator.services.mozilla.com/D7042
--HG--
extra : rebase_source : 4a016d1dce77a269b886467c9343dab125079a8f
extra : amend_source : 4e9133e70932f382e0b5df9e487978b95d05781b
These maps hold strong references which complicate nsThread lifetime handling
considerably, and only have a couple of fringe uses. We have a linked list of
active threads that the thread manager can use for its internal enumeration
purposes, and the external uses are easily done away with, so there doesn't
seem to be much reason to keep the map around.
MozReview-Commit-ID: x7dsj6C4x8
--HG--
extra : source : 5f870621361012ba459943212d8c68a9ff81cb16
extra : intermediate-source : 89a0c0874d400dd324df6fc3627c0c47d130df19
extra : histedit_source : bbd7900e3d754bde925a411c10aa30a1d6e22edd
Most of the times when we automatically create nsThread wrappers for threads
that don't already have them, we don't actually need the event targets, since
those threads don't run XPCOM event loops. Aside from wasting memory, actually
creating these event loops can lead to leaks if a thread tries to dispatch a
runnable to the queue which creates a reference cycle with the thread.
Not creating the event queues for threads that don't actually need them helps
avoid those foot guns, and also makes it easier to figure out which treads
actually run XPCOM event loops.
MozReview-Commit-ID: Arck4VQqdne
--HG--
extra : source : a03a61d6d724503c3b7c5e31fe32ced1f5d1c219
extra : intermediate-source : 5152af6ab3e399216ef6db8f060c257b2ffbd330
extra : histedit_source : ef06000344416e0919f536d5720fa979d2d29c66%2C4671676b613dc3e3ec762edf5d72a2ffbe6fca3f
These maps hold strong references which complicate nsThread lifetime handling
considerably, and only have a couple of fringe uses. We have a linked list of
active threads that the thread manager can use for its internal enumeration
purposes, and the external uses are easily done away with, so there doesn't
seem to be much reason to keep the map around.
MozReview-Commit-ID: x7dsj6C4x8
--HG--
extra : rebase_source : 897e2d32d1dfee24d51459065925fb9b41fa543a
extra : source : 5f870621361012ba459943212d8c68a9ff81cb16
Most of the times when we automatically create nsThread wrappers for threads
that don't already have them, we don't actually need the event targets, since
those threads don't run XPCOM event loops. Aside from wasting memory, actually
creating these event loops can lead to leaks if a thread tries to dispatch a
runnable to the queue which creates a reference cycle with the thread.
Not creating the event queues for threads that don't actually need them helps
avoid those foot guns, and also makes it easier to figure out which treads
actually run XPCOM event loops.
MozReview-Commit-ID: Arck4VQqdne
--HG--
extra : rebase_source : fcf8fa50e748c4b54c3bb1997575d9ffd4cbaae1
extra : source : a03a61d6d724503c3b7c5e31fe32ced1f5d1c219
These maps hold strong references which complicate nsThread lifetime handling
considerably, and only have a couple of fringe uses. We have a linked list of
active threads that the thread manager can use for its internal enumeration
purposes, and the external uses are easily done away with, so there doesn't
seem to be much reason to keep the map around.
MozReview-Commit-ID: x7dsj6C4x8
--HG--
extra : rebase_source : 88c56fa4f5da97f33ade08d892c3d8c42666307e
Most of the times when we automatically create nsThread wrappers for threads
that don't already have them, we don't actually need the event targets, since
those threads don't run XPCOM event loops. Aside from wasting memory, actually
creating these event loops can lead to leaks if a thread tries to dispatch a
runnable to the queue which creates a reference cycle with the thread.
Not creating the event queues for threads that don't actually need them helps
avoid those foot guns, and also makes it easier to figure out which treads
actually run XPCOM event loops.
MozReview-Commit-ID: Arck4VQqdne
--HG--
extra : rebase_source : 02c5572b92ee48c11697d90941336e10c03d49cf
There are surprisingly many of them.
(Plus a couple of unnecessary checks after `new` calls that were nearby.)
--HG--
extra : rebase_source : 47b6d5d7c5c99b1b50b396daf7a3b67abfd74fc1
This moves the code that detects very low memory scenarios and grabs memory
reports from the main thread event-loop to the available memory tracker.
Besides removing the overhead of the check from the event-loop code this
increases the likeliness of the reports being gathered by sampling at a
higher frequency but only when we already detected a low-memory scenario. Last
but not least this add checks for low commit-space detection alongside low
virtual-memory detection.
Differential Revision: https://phabricator.services.mozilla.com/D3669
--HG--
extra : moz-landing-system : lando
This new id is added in the PerformanceInfo data and helps consumers distinguish
counters.
MozReview-Commit-ID: 7kEmqJcVggM
--HG--
extra : rebase_source : 40cca4c937f846db93ec1315036ad1bac04bc762
