G1 does not retire allocation buffers after reference processing work when -XX:+ParallelRefProcEnabled is enabled. This causes wrong calculation of PLAB sizes, as the amount of space wasted is not updated correctly.
Reviewed-by: brutisso
Revert JDK-6976350 because it does not improve PLAB fragmentation. To the contrary, it tends to increase the amount of wasted space with many threads.
Reviewed-by: brutisso
Create G1ParGCAllocBufferContainer to contain two buffers instead of previously using one buffer, in order to hold the first priority buffer longer. Thus, when some large objects hits the value of free space left in the first priority buffer it has an alternative to fit in the second priority buffer while the first priority buffer is given more chances to try allocating smaller objects. Overall, it will improve heap space efficiency.
Reviewed-by: johnc, jmasa, brutisso
Reset the fields in ParGCAllocBuffer, that are used for accumulating values for the ResizePLAB sensors in PLABStats, to zero after flushing the values to the PLABStats fields. Flush PLABStats values only when retiring the final allocation buffers prior to disposing of a G1ParScanThreadState object, rather than when retiring every allocation buffer.
Reviewed-by: jwilhelm, jmasa, ysr
Employ PLABStats instances to record information about survivor and old PLABs, and use the recorded stats to adjust the sizes of survivor and old PLABS.
Reviewed-by: johnc, ysr
2012-08-06 12:20:14 -07:00
Renamed from hotspot/src/share/vm/gc_implementation/parNew/parGCAllocBuffer.hpp (Browse further)
