Use zero based compressed oops if java heap is below 32gb and unscaled compressed oops if java heap is below 4gb.
Reviewed-by: never, twisti, jcoomes, coleenp
Allocate worker-local overflow stacks, introduced in 6819891, along with ParNewGeneration, rather than with the per-scavenge ParScanThreadState.
Reviewed-by: jmasa
Call newly created CollectedHeap::dump_{pre,post}_full_gc before and after every stop-world full collection cycle on GenCollectedHeap and ParallelScavengeHeap. (Support for G1CollectedHeap forthcoming under CR 6810861.) Small modifications to existing heap dumping and class histogram implementation, especially to allow multiple on-the-fly histos/dumps by the VM thread during a single safepoint.
Reviewed-by: jmasa, alanb, mchung
Increased the default and maximum size of the CMS marking stack and the size of the parallel workers' work queues in 64-bit mode. The latter was accomplished by an increase in the width of the Taskqueue's Age struct and its Tag field in 64-bit mode.
Reviewed-by: jmasa, tonyp
Avoid overflow list walk in CMS & ParNew when it is unnecessary. Fix a couple of correctness issues, including a C-heap leak, in ParNew at the intersection of promotion failure, work queue overflow and object array chunking. Add stress testing option and related assertion checking.
Reviewed-by: jmasa
In os::Linux::rebuild_cpu_to_node_map() fix the size of the CPU bitmap. Fixed arithmetic in MutableNUMASpace::adaptive_chunk_size() that could cause overflows and underflows of the chunk_size variable.
Reviewed-by: apetrusenko
The default value of UseVMInterruptibleIO is changed to false for JDK 7, but the default isn't changed for JDK 6 and earlier.
Reviewed-by: never, acorn, dholmes, kamg, alanb
When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery.
Reviewed-by: apetrusenko, jcoomes
Experimental() flags will protect features of an experimental nature that are not supported in the regular product build. Made UseG1GC an experimental flag.
Reviewed-by: jmasa, kamg, coleenp
