da63f23e68
This finishes the refactoring of the HPA/psset interactions the past few commits have been building towards. Rather than the HPA removing and then reinserting hpdatas, it simply begins updates and ends them. These updates can set flags on the hpdata that prevent it from being returned for certain types of requests. For example, it can call hpdata_alloc_allowed_set(hpdata, false) during an update, at which point the given hpdata will no longer be returned for psset_pick_alloc requests. This has various of benefits: - It maintains stats correctness during purges and hugifies. - It allows simpler and more explicit concurrency control for the various special cases (e.g. allocations are disallowed during purge, but not during hugify). - It lets allocations and deallocations avoid disturbing the purging and hugification orderings. If an hpdata "loses its place" in one of the queues just do to an alloc / dalloc, it can result in pathological edge cases where very hot, very full hugepages never get hugified (and cold extents on the same hugepage as hot ones never get purged). The key benefit though is that tracking hpdatas to be purged / hugified in a principled way will let us do delayed purging and hugification. Eventually this will let us move these operations to background threads, but in the short term the benefit is that it will let us have global purging policies (e.g. purge when the entire arena has too many dirty pages, rather than any particular hugepage). |
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bin | ||
build-aux | ||
doc | ||
doc_internal | ||
include | ||
m4 | ||
msvc | ||
scripts | ||
src | ||
test | ||
.appveyor.yml | ||
.autom4te.cfg | ||
.cirrus.yml | ||
.clang-format | ||
.gitattributes | ||
.gitignore | ||
.travis.yml | ||
autogen.sh | ||
ChangeLog | ||
config.stamp.in | ||
configure.ac | ||
COPYING | ||
INSTALL.md | ||
jemalloc.pc.in | ||
Makefile.in | ||
README | ||
run_tests.sh | ||
TUNING.md |
jemalloc is a general purpose malloc(3) implementation that emphasizes fragmentation avoidance and scalable concurrency support. jemalloc first came into use as the FreeBSD libc allocator in 2005, and since then it has found its way into numerous applications that rely on its predictable behavior. In 2010 jemalloc development efforts broadened to include developer support features such as heap profiling and extensive monitoring/tuning hooks. Modern jemalloc releases continue to be integrated back into FreeBSD, and therefore versatility remains critical. Ongoing development efforts trend toward making jemalloc among the best allocators for a broad range of demanding applications, and eliminating/mitigating weaknesses that have practical repercussions for real world applications. The COPYING file contains copyright and licensing information. The INSTALL file contains information on how to configure, build, and install jemalloc. The ChangeLog file contains a brief summary of changes for each release. URL: http://jemalloc.net/