| commit | b75057b6876cfa03696309c7a9ca3e2788896f34 | [log] [tgz] |
|---|---|---|
| author | Martin Kustermann <kustermann@google.com> | Wed Jun 26 11:34:48 2019 +0000 |
| committer | commit-bot@chromium.org <commit-bot@chromium.org> | Wed Jun 26 11:34:48 2019 +0000 |
| tree | cf29ba9fea7dc85f98b86df19ec05fedabd65a89 | |
| parent | 9e3b44b29978021d77a1e94823e272b2e8a52db1 [diff] |
[vm/concurrency] Introduce concept of Isolate Groups
An Isolate Group (IG) is a collection of isolates which were spawned from the
same source. This allows the VM to:
* have a guarantee that all isolates within one IG can safely exchange
structured objects (currently we rely on embedder for this
guarantee)
* hot-reload all isolates together (currently we only reload one
isolate, leaving same-source isolates in inconsistent state)
* make a shared heap for all isolates from the same IG, which paves
the way for faster communication and sharing of immutable objects.
All isolates within one IG will share the same IsolateGroupSource.
**Embedder changes**
This change makes breaking embedder API changes to support this new
concept of Isolate Groups: The existing isolate lifecycle callbacks
given to Dart_Initialize will become Isolate Group lifecycle callbacks.
A new callback `initialize_isolate` callback will be added which can
initialize a new isolate within an existing IG.
Existing embedders can be updated by performing the following renames
Dart_CreateIsolate -> Dart_CreateIsolateGroup
Dart_IsolateCreateCallback -> Dart_IsolateGroupCreateCallback
Dart_IsolateCleanupCallback -> Dart_IsolateGroupShutdownCallback
Dart_CreateIsolateFromKernel -> Dart_CreateIsolateGroupFromKernel
Dart_CurrentIsolateData -> Dart_CurrentIsolateGroupData
Dart_IsolateData -> Dart_IsolateGroupData
Dart_GetNativeIsolateData -> Dart_GetNativeIsolateGroupData
Dart_InitializeParams.create -> Dart_InitializeParams.create_group
Dart_InitializeParams.cleanup -> Dart_InitializeParams.shutdown_group
Dart_InitializeParams.shutdown -> Dart_InitializeParams.shutdown_isolate
By default `Isolate.spawn` will cause the creation of a new IG.
Though an embedder can opt-into supporting multiple isolates within one IG by
providing a callback to the newly added `Dart_InitializeParams.initialize_isolate`.
The responsibility of this new callback is to initialize an existing
isolate (which was setup by re-using source code from the spawning
isolate - i.e. the one which used `Isolate.spawn`) by setting native
resolvers, initializing global state, etc.
Issue https://github.com/dart-lang/sdk/issues/36648
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: I82437ac017ca33018d45e02f353b0672db155f6a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/105241
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
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