The pai_t interface implements C-style polymorphism via function pointers
to abstract over PAC and HPA. This abstraction provides no real benefit:
only two implementations exist, the dispatcher already knows which one to
use, and HPA stubs 2 of 5 operations. Remove the runtime dispatch in
favor of direct calls.
This commit:
- Promotes pac_alloc/expand/shrink/dalloc/time_until_deferred_work to
external linkage and replaces the pai_t *self parameter with pac_t *pac.
- Promotes hpa_alloc/expand/shrink/dalloc/time_until_deferred_work to
external linkage and replaces pai_t *self with hpa_shard_t *shard.
- Updates hpa_dalloc_batch's signature to take hpa_shard_t * directly
and removes the hpa_from_pai container-of helper. Updates internal
callers in hpa_alloc, hpa_dalloc, and hpa_sec_flush_impl.
- Drops the vtable assignments from pac_init() and hpa_shard_init().
- Replaces pai_alloc/dalloc/etc. dispatch in pa.c with direct calls.
HPA expand and shrink (which are unconditional failure stubs) are
skipped entirely for HPA-owned extents.
- Removes the pa_get_pai() helper.
- Updates tests in test/unit/hpa.c and test/unit/hpa_sec_integration.c
to call hpa_alloc/dalloc/etc. directly.
The pai_t struct field stays as dead weight in pac_t and hpa_shard_t;
it is removed in the next commit along with pai.h itself.
No behavioral changes.
Three changes to make pa_microbench easier to drive for fragmentation
experiments:
- Replace HPA_SHARD_OPTS_DEFAULT use with a single editable g_hpa_opts
global. The microbench does not consult MALLOC_CONF for HPA shard opts,
so this is the place to set the baseline configuration (slab_max_alloc,
hugification_threshold, dirty_mult, hugify_delay_ms, purge_threshold,
hugify_style, etc.).
- Add -n/--nshards N to override the shard count derived from the trace.
When set, each event is routed to (event->shard_ind % N), letting us
study the impact of arena consolidation. Without the flag the behavior
is unchanged (num_shards = max_shard_id + 1).
- Bump MAX_ALLOCATIONS from 10M to 200M so the full ~50M-event adfinder
trace (and similar) fits in the in-memory event buffer.
pa_microbench was creating its own emap_t per shard on top of the
arena_emap_global that JET malloc initializes during jet_malloc(16)
at startup, breaking the production assumption of one rtree per
process. Fix it by reusing the existing JET emap.
Additionally, added a GitHub Action to ensure no more trailing
whitespace will creep in again in the future.
I'm excluding Markdown files from this check, since trailing whitespace
is significant there, and also excluding `build-aux/install-sh` because
there is significant trailing whitespace on the line that sets
`defaultIFS`.
Summary:
Per issue #2356, some CXX compilers may optimize away the
new/delete operation in stress/cpp/microbench.cpp.
Thus, this commit (1) bumps the time interval to 1 if it is 0, and
(2) modifies the pointers in the microbench to volatile.
The mallctlbymib_long helper was copy-pasted from mallctlbymib_short, and
incorrectly used its output variable (a char *) rather than the output variable
of the mallctl call it was using (a uint64_t), causing breakages when
sizeof(char *) differed from sizeof(uint64_t).
Algorithmically, a size greater than 1024 ZB could access one-past-the-end of
the sizes array. This couldn't really happen since SIZE_MAX is less than 1024
ZB on all platforms we support (and we pick the arguments to this function to be
reasonable anyways), but it's not like there's any reason *not* to fix it,
either.
This checks whether or not we're reentrant using thread-local data, and, if we
are, moves certain internal allocations to use arena 0 (which should be properly
initialized after bootstrapping).
The immediate thing this allows is spinning up threads in arena_new, which will
enable spinning up background threads there.
Create and use FMT* macros that are equivalent to the PRI* macros that
inttypes.h defines. This allows uniform use of the Unix-specific format
specifiers, e.g. "%zu", as well as avoiding Windows-specific definitions
of e.g. PRIu64.
Add ffs()/ffsl() support for compiling with gcc.
Extract compatibility definitions of ENOENT, EINVAL, EAGAIN, EPERM,
ENOMEM, and ENORANGE into include/msvc_compat/windows_extra.h and
use the file for tests as well as for core jemalloc code.
This adds a new `sdallocx` function to the external API, allowing the
size to be passed by the caller. It avoids some extra reads in the
thread cache fast path. In the case where stats are enabled, this
avoids the work of calculating the size from the pointer.
An assertion validates the size that's passed in, so enabling debugging
will allow users of the API to debug cases where an incorrect size is
passed in.
The performance win for a contrived microbenchmark doing an allocation
and immediately freeing it is ~10%. It may have a different impact on a
real workload.
Closes#28
