Improves the space overhead of compaction from O(size of live objects) to O(number of live objects).
Future work includes:
- a smaller, faster representation the forwarding table via a bitmap of used allocation units
- sorting class sizes off-heap to allow sliding classes
- running forwarding in parallel
Removes unnecessary sweep from evacuating compactor.
Change-Id: If0991bfb75573201c6e8feed142ca0cc69fccab4
Bug: https://github.com/dart-lang/sdk/issues/30978
Reviewed-on: https://dart-review.googlesource.com/15988
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Erik Corry <erikcorry@google.com>
stack_limit_,
stack_overflow_flags_,
saved_stack_limit_,
stack_overflow_count_ and
other interrupts mask fields from Isolate structure to Thread structure
- Change the stack overflow check in the prolog to load the stack limit
from the THR register, this removes the back to back dependent loads to
load the stack limit from the Isolate structure
R=johnmccutchan@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/1812753002 .
Remove typedef hack by templatizing the shared structures,
parameterized by block size.
Smaller marking stack blocks are needed for better work distribution during parallel GC.
As a consequence, MarkingStack and StoreBuffer have separate global caches of empty blocks.
Also, use inheritance to differentiate: only StoreBuffer needs the threshold-checking functionality.
BUG=
R=johnmccutchan@google.com
Review URL: https://codereview.chromium.org//1350933004 .
Prepares for parallel processing of a shared marking stack, but code remains
unsynchronized for now.
Share basic data structures with the StoreBuffer.
BUG=
Review URL: https://codereview.chromium.org//1271833002 .
Add infrastructure to enable all threads in an isolate to rendezvous at GC-safe points, and exercise it through unit tests.
* Use existing interrupt mechanism for Dart threads, but a cooperative approach for non-Dart threads (concurrent compiler, etc.): they must periodically call CheckSafepoint (may block).
* Add unit tests to exercise and verify various scenarios: organizing the rendezvous from helper/main thread, with/without Dart code executing, etc.
The next step is to use this interface in old-space allocation and garbage collection, respectively, to allow helper threads to perform allocations that potentially trigger GC (needed for concurrent compiler).
Limitations:
* A thread that is executing a long-running native function is currently not considered at a safepoint, and will delay the rendezvous until it returns to Dart or indirectly calls CheckSafepoint. In a future CL, we can use the saved stack pointer to detect and support this case, and intercept the thread if/when it re-enters Dart or the VM.
BUG=
R=iposva@google.com
Review URL: https://codereview.chromium.org//1259223005 .
Keep cache of empty blocks shared among all isolates, limited in size.
Change overflow threshold check to include partially filled blocks.
Make Isolate::store_buffer_ a pointer, now that it's less frequently accessed, to keep the offsets of other fields small
BUG=
R=iposva@google.com
Review URL: https://codereview.chromium.org//1173043002.
This will deduplicate its entries. StoreBufferBlock might be contain the same large object dozens of times and without deduplication this will severely degrade GC performance by revisiting the same large object for every time it is recorded in the StoreBufferBlock.
BUG=dart:10048
Review URL: https://codereview.chromium.org//14348026
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@21766 260f80e4-7a28-3924-810f-c04153c831b5
The purpose of this change is twofold:
1. Source in the bin directory can now use the same assertions as
source in the vm directory. The ASSERT macro used by the code
in runtime/bin was just defined to use assert from the standard
C library.
2. Moving other implementation parts from runtime/vm to
runtime/platform (e.g. classes Monitor and Mutex) for sharing
between runtime/bin and runtime/vm will be easier as these
implementations rely on these assertion macros.
Created two gypi files for the platform directory. One for the
headers and one for the source. The source one is only included
when building the VM library and will be present in libdart.a
when the dart executable is linked.
All the code for asserts is still in the dart namespace.
Also re-arranged the order of includes to be alphabetically in
the files touched.
R=ager@google.com, iposva@google.com
BUG=
TEST=
Review URL: http://codereview.chromium.org//9189003
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@3335 260f80e4-7a28-3924-810f-c04153c831b5
Ryan Macnak