Mercurial > hg > truffle
changeset 12178:84683e78e713
8019902: G1: Use the average heap size rather than the minimum heap size to calculate the region size
Reviewed-by: tonyp, tschatzl, sjohanss
author | brutisso |
---|---|
date | Fri, 30 Aug 2013 07:31:47 +0200 |
parents | 0d59407e7e09 |
children | f175e3678be2 a701c16e8bbf |
files | src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp src/share/vm/gc_implementation/g1/heapRegion.cpp src/share/vm/gc_implementation/g1/heapRegion.hpp |
diffstat | 3 files changed, 13 insertions(+), 12 deletions(-) [+] |
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--- a/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Thu Aug 29 06:53:16 2013 -0700 +++ b/src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp Fri Aug 30 07:31:47 2013 +0200 @@ -168,7 +168,15 @@ // Set up the region size and associated fields. Given that the // policy is created before the heap, we have to set this up here, // so it's done as soon as possible. - HeapRegion::setup_heap_region_size(Arguments::min_heap_size()); + + // It would have been natural to pass initial_heap_byte_size() and + // max_heap_byte_size() to setup_heap_region_size() but those have + // not been set up at this point since they should be aligned with + // the region size. So, there is a circular dependency here. We base + // the region size on the heap size, but the heap size should be + // aligned with the region size. To get around this we use the + // unaligned values for the heap. + HeapRegion::setup_heap_region_size(InitialHeapSize, MaxHeapSize); HeapRegionRemSet::setup_remset_size(); G1ErgoVerbose::initialize();
--- a/src/share/vm/gc_implementation/g1/heapRegion.cpp Thu Aug 29 06:53:16 2013 -0700 +++ b/src/share/vm/gc_implementation/g1/heapRegion.cpp Fri Aug 30 07:31:47 2013 +0200 @@ -149,18 +149,11 @@ // many regions in the heap (based on the min heap size). #define TARGET_REGION_NUMBER 2048 -void HeapRegion::setup_heap_region_size(uintx min_heap_size) { - // region_size in bytes +void HeapRegion::setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size) { uintx region_size = G1HeapRegionSize; if (FLAG_IS_DEFAULT(G1HeapRegionSize)) { - // We base the automatic calculation on the min heap size. This - // can be problematic if the spread between min and max is quite - // wide, imagine -Xms128m -Xmx32g. But, if we decided it based on - // the max size, the region size might be way too large for the - // min size. Either way, some users might have to set the region - // size manually for some -Xms / -Xmx combos. - - region_size = MAX2(min_heap_size / TARGET_REGION_NUMBER, + size_t average_heap_size = (initial_heap_size + max_heap_size) / 2; + region_size = MAX2(average_heap_size / TARGET_REGION_NUMBER, (uintx) MIN_REGION_SIZE); }
--- a/src/share/vm/gc_implementation/g1/heapRegion.hpp Thu Aug 29 06:53:16 2013 -0700 +++ b/src/share/vm/gc_implementation/g1/heapRegion.hpp Fri Aug 30 07:31:47 2013 +0200 @@ -361,7 +361,7 @@ // CardsPerRegion). All those fields are considered constant // throughout the JVM's execution, therefore they should only be set // up once during initialization time. - static void setup_heap_region_size(uintx min_heap_size); + static void setup_heap_region_size(size_t initial_heap_size, size_t max_heap_size); enum ClaimValues { InitialClaimValue = 0,