Mercurial > hg > openjdk > jdk8 > hotspot
changeset 4761:8dbc025ff709
8015422: Large performance hit when the StringTable is walked twice in Parallel Scavenge
Summary: Combine the calls to StringTable::unlink and StringTable::oops_do in Parallel Scavenge.
Reviewed-by: pliden, coleenp
| author | stefank |
|---|---|
| date | Mon, 27 May 2013 12:58:42 +0200 |
| parents | 95c00927be11 |
| children | f41a577cffb0 5534bd30c151 |
| files | src/share/vm/classfile/symbolTable.cpp src/share/vm/classfile/symbolTable.hpp src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp |
| diffstat | 3 files changed, 11 insertions(+), 7 deletions(-) [+] |
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--- a/src/share/vm/classfile/symbolTable.cpp Mon May 27 12:56:34 2013 +0200 +++ b/src/share/vm/classfile/symbolTable.cpp Mon May 27 12:58:42 2013 +0200 @@ -737,7 +737,7 @@ return result; } -void StringTable::unlink(BoolObjectClosure* is_alive) { +void StringTable::unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f) { // Readers of the table are unlocked, so we should only be removing // entries at a safepoint. assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); @@ -748,6 +748,9 @@ assert(!entry->is_shared(), "CDS not used for the StringTable"); if (is_alive->do_object_b(entry->literal())) { + if (f != NULL) { + f->do_oop((oop*)entry->literal_addr()); + } p = entry->next_addr(); } else { *p = entry->next();
--- a/src/share/vm/classfile/symbolTable.hpp Mon May 27 12:56:34 2013 +0200 +++ b/src/share/vm/classfile/symbolTable.hpp Mon May 27 12:58:42 2013 +0200 @@ -272,7 +272,10 @@ // GC support // Delete pointers to otherwise-unreachable objects. - static void unlink(BoolObjectClosure* cl); + static void unlink_or_oops_do(BoolObjectClosure* cl, OopClosure* f); + static void unlink(BoolObjectClosure* cl) { + unlink_or_oops_do(cl, NULL); + } // Invoke "f->do_oop" on the locations of all oops in the table. static void oops_do(OopClosure* f);
--- a/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Mon May 27 12:56:34 2013 +0200 +++ b/src/share/vm/gc_implementation/parallelScavenge/psScavenge.cpp Mon May 27 12:58:42 2013 +0200 @@ -450,11 +450,9 @@ reference_processor()->enqueue_discovered_references(NULL); } - // Unlink any dead interned Strings - StringTable::unlink(&_is_alive_closure); - // Process the remaining live ones - PSScavengeRootsClosure root_closure(promotion_manager); - StringTable::oops_do(&root_closure); + // Unlink any dead interned Strings and process the remaining live ones. + PSScavengeRootsClosure root_closure(promotion_manager); + StringTable::unlink_or_oops_do(&_is_alive_closure, &root_closure); // Finally, flush the promotion_manager's labs, and deallocate its stacks. PSPromotionManager::post_scavenge();