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
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 takes 16 bytes off of the allocated size of each instance.
MozReview-Commit-ID: AhfN6MWvVL1
--HG--
extra : rebase_source : badc6ab690f2c4e0184ac0b51b29f81fb11279c6
extra : absorb_source : 0f685515a6946c89e9467c8b1e8548c989b1907b
extra : histedit_source : 7bfb5db39b23c1d262819c22a6e5fcd884c52504
This was moved out of nsThread in bug 1350432, but some dead code was left
behind.
MozReview-Commit-ID: BOhykHyIEPp
--HG--
extra : rebase_source : 21d4f95a019ba10851fba1efc588d6c2678aed85
Later patches add support for Windows. OS-X will need a follow-up.
MozReview-Commit-ID: DDd6uir4KzM
--HG--
extra : source : b4394660fde2b05e972c491246570d8f79d8a7c6
extra : absorb_source : 063bc5db64faa9311ac9db99259cd477fb8fcf7e
This change stores the base allocation address and actual allocated stack size
(as opposed to the requested size, which may be 0), so that we can map them to
VM regions in a memory reporter.
MozReview-Commit-ID: IZbbyQ9pKHr
--HG--
extra : source : 391b97f0e5c029880d4a1ae697463cfcb8839116
This will allow us to enumerate active threads in order to report their
memory.
MozReview-Commit-ID: IExELSkFdwB
--HG--
extra : source : 2916b5e05b6d100e91448f21cb4082e41a86e87c
Later patches add support for Windows. OS-X will need a follow-up.
MozReview-Commit-ID: DDd6uir4KzM
--HG--
extra : rebase_source : a28826d3331d057f4d35bec56da7738a727d9768
This change stores the base allocation address and actual allocated stack size
(as opposed to the requested size, which may be 0), so that we can map them to
VM regions in a memory reporter.
MozReview-Commit-ID: IZbbyQ9pKHr
--HG--
extra : rebase_source : 1b61bfd63931ce9e2bf9a71905468336971d0956
This will allow us to enumerate active threads in order to report their
memory.
MozReview-Commit-ID: IExELSkFdwB
--HG--
extra : rebase_source : 94b63857357639b201b85bdd7bfc4fbe1d4b7f62
Now uses StaticPrefs instead of DOMPrefs, and how we count dispatches for Workers.
MozReview-Commit-ID: DTumwcI5bG
--HG--
extra : rebase_source : 0cf5312e714fb260c01df647b2cd1fcc28ffc415
PerformanceCounters are currently disabled in two ways:
- a preference that's off by default "dom.performance.enable_scheduler_timing"
- calls made only for nightly using #ifndef RELEASE_OR_BETA
In order to simplify the code, let's remove the #ifndef and rely only on the pref.
That will also allows us to use the feature in every version going forward.
The performance will not be impacted since the current code is already using
the (cached) pref value to determine if the counters are used.
MozReview-Commit-ID: 47t2M1O13aH
--HG--
extra : rebase_source : e129e1829f1dc37c019e50e156474c4876d6d6cb
Adds a PeformanceCounter class that is used in DocGroup and WorkerPrivate
to track runnables execution and dispatch counts.
MozReview-Commit-ID: 51DLj6ORD2O
--HG--
extra : rebase_source : b481c9aa3b735569722bb7472872ec2d22adcb89
This patch refactors the nsThread event queue to clean it up and to make it easier to restructure. The fundamental concepts are as follows:
Each nsThread will have a pointer to a refcounted SynchronizedEventQueue. A SynchronizedEQ takes care of doing the locking and condition variable work when posting and popping events. For the actual storage of events, it delegates to an AbstractEventQueue data structure. It keeps a UniquePtr to the AbstractEventQueue that it uses for storage.
Both SynchronizedEQ and AbstractEventQueue are abstract classes. There is only one concrete implementation of SynchronizedEQ in this patch, which is called ThreadEventQueue. ThreadEventQueue uses locks and condition variables to post and pop events the same way nsThread does. It also encapsulates the functionality that DOM workers need to implement their special event loops (PushEventQueue and PopEventQueue). In later Quantum DOM work, I plan to have another SynchronizedEQ implementation for the main thread, called SchedulerEventQueue. It will have special code for the cooperatively scheduling threads in Quantum DOM.
There are two concrete implementations of AbstractEventQueue in this patch: EventQueue and PrioritizedEventQueue. EventQueue replaces the old nsEventQueue. The other AbstractEventQueue implementation is PrioritizedEventQueue, which uses multiple queues for different event priorities.
The final major piece here is ThreadEventTarget, which splits some of the code for posting events out of nsThread. Eventually, my plan is for multiple cooperatively scheduled nsThreads to be able to share a ThreadEventTarget. In this patch, though, each nsThread has its own ThreadEventTarget. The class's purpose is just to collect some related code together.
One final note: I tried to avoid virtual dispatch overhead as much as possible. Calls to SynchronizedEQ methods do use virtual dispatch, since I plan to use different implementations for different threads with Quantum DOM. But all the calls to EventQueue methods should be non-virtual. Although the methods are declared virtual, all the classes used are final and the concrete classes involved should all be known through templatization.
MozReview-Commit-ID: 9Evtr9oIJvx
For some reason, I continuously ran into windows x64 specific failures when
trying to read this heap allocated data while the main thread was paused. I
don't know specifically how this happened, but I am able to avoid it by instead
directly allocating the buffer in a `mozilla::Array` in static storage, and
copying that data instead.
MozReview-Commit-ID: 473d6IpHlc4
Randell Jesup
shindli
Kris Maglione
Narcis Beleuzu
Noemi Erli
Gabriele Svelto
Cosmin Sabou
Coroiu Cristina
Brindusan Cristian
Tarek Ziadé
Nathan Froyd
Sebastian Hengst
Andrew McCreight
Stone Shih
Bill McCloskey
Carsten "Tomcat" Book
Michael Layzell