archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-09-21 11:34:38 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

8007036: G1: Too many old regions added to last mixed GC

Browse source 
Stop adding old regions to collection set when the remaining reclaimable bytes reaches, or goes below, G1HeapWastePercent. Changes were also reviewed by Vitaly Davidovich <vitalyd@gmail.com>.

Reviewed-by: brutisso
This commit is contained in:
John Cuthbertson 2013-03-04 12:42:14 -08:00
parent 37aa83449e
commit a3a42c48e8
4 changed files with 101 additions and 55 deletions
Download patch file Download diff file Expand all files Collapse all files

37
hotspot/src/share/vm/gc_implementation/g1/collectionSetChooser.cpp
View file

@ -146,43 +146,6 @@ void CollectionSetChooser::sort_regions() {
verify();
}
uint CollectionSetChooser::calc_min_old_cset_length() {
// The min old CSet region bound is based on the maximum desired
// number of mixed GCs after a cycle. I.e., even if some old regions
// look expensive, we should add them to the CSet anyway to make
// sure we go through the available old regions in no more than the
// maximum desired number of mixed GCs.
//
// The calculation is based on the number of marked regions we added
// to the CSet chooser in the first place, not how many remain, so
// that the result is the same during all mixed GCs that follow a cycle.
const size_t region_num = (size_t) _length;
const size_t gc_num = (size_t) G1MixedGCCountTarget;
size_t result = region_num / gc_num;
// emulate ceiling
if (result * gc_num < region_num) {
result += 1;
}
return (uint) result;
}
uint CollectionSetChooser::calc_max_old_cset_length() {
// The max old CSet region bound is based on the threshold expressed
// as a percentage of the heap size. I.e., it should bound the
// number of old regions added to the CSet irrespective of how many
// of them are available.
G1CollectedHeap* g1h = G1CollectedHeap::heap();
const size_t region_num = g1h->n_regions();
const size_t perc = (size_t) G1OldCSetRegionThresholdPercent;
size_t result = region_num * perc / 100;
// emulate ceiling
if (100 * result < region_num * perc) {
result += 1;
}
return (uint) result;
}
void CollectionSetChooser::add_region(HeapRegion* hr) {
assert(!hr->isHumongous(),