Commit Graph

74 Commits

Author SHA1 Message Date
Jason Evans
a7a6f5bc96 Rename extent_node_t to extent_t. 2016-05-16 12:21:28 -07:00
Jason Evans
ba5c709517 Remove quarantine support. 2016-05-13 10:25:05 -07:00
Jason Evans
1c35f63797 Guard tsdn_tsd() call with tsdn_null() check. 2016-05-11 16:52:58 -07:00
Jason Evans
7790a0ba40 Fix chunk accounting related to triggering gdump profiles.
Fix in place huge reallocation to update the chunk counters that are
used for triggering gdump profiles.
2016-05-11 00:56:30 -07:00
Jason Evans
c1e00ef2a6 Resolve bootstrapping issues when embedded in FreeBSD libc.
b2c0d6322d (Add witness, a simple online
locking validator.) caused a broad propagation of tsd throughout the
internal API, but tsd_fetch() was designed to fail prior to tsd
bootstrapping.  Fix this by splitting tsd_t into non-nullable tsd_t and
nullable tsdn_t, and modifying all internal APIs that do not critically
rely on tsd to take nullable pointers.  Furthermore, add the
tsd_booted_get() function so that tsdn_fetch() can probe whether tsd
bootstrapping is complete and return NULL if not.  All dangerous
conversions of nullable pointers are tsdn_tsd() calls that assert-fail
on invalid conversion.
2016-05-10 22:51:33 -07:00
Jason Evans
3ef51d7f73 Optimize the fast paths of calloc() and [m,d,sd]allocx().
This is a broader application of optimizations to malloc() and free() in
f4a0f32d34 (Fast-path improvement:
reduce # of branches and unnecessary operations.).

This resolves #321.
2016-05-06 14:37:39 -07:00
Jason Evans
90827a3f3e Fix huge_palloc() regression.
Split arena_choose() into arena_[i]choose() and use arena_ichoose() for
arena lookup during internal allocation.  This fixes huge_palloc() so
that it always succeeds during extent node allocation.

This regression was introduced by
66cd953514 (Do not allocate metadata via
non-auto arenas, nor tcaches.).
2016-05-03 17:19:15 -07:00
Jason Evans
66cd953514 Do not allocate metadata via non-auto arenas, nor tcaches.
This assures that all internally allocated metadata come from the
first opt_narenas arenas, i.e. the automatically multiplexed arenas.
2016-04-22 15:19:59 -07:00
Jason Evans
b2c0d6322d Add witness, a simple online locking validator.
This resolves #358.
2016-04-14 02:09:28 -07:00
Chris Peterson
a82070ef5f Add JEMALLOC_ALLOC_JUNK and JEMALLOC_FREE_JUNK macros
Replace hardcoded 0xa5 and 0x5a junk values with JEMALLOC_ALLOC_JUNK and
JEMALLOC_FREE_JUNK macros, respectively.
2016-03-31 11:23:29 -07:00
Jason Evans
0c516a00c4 Make *allocx() size class overflow behavior defined.
Limit supported size and alignment to HUGE_MAXCLASS, which in turn is
now limited to be less than PTRDIFF_MAX.

This resolves #278 and #295.
2016-02-25 15:29:49 -08:00
Jason Evans
243f7a0508 Implement decay-based unused dirty page purging.
This is an alternative to the existing ratio-based unused dirty page
purging, and is intended to eventually become the sole purging
mechanism.

Add mallctls:
- opt.purge
- opt.decay_time
- arena.<i>.decay
- arena.<i>.decay_time
- arenas.decay_time
- stats.arenas.<i>.decay_time

This resolves #325.
2016-02-19 20:56:21 -08:00
Qi Wang
f4a0f32d34 Fast-path improvement: reduce # of branches and unnecessary operations.
- Combine multiple runtime branches into a single malloc_slow check.
- Avoid calling arena_choose / size2index / index2size on fast path.
- A few micro optimizations.
2015-11-10 14:28:34 -08:00
Jason Evans
d260f442ce Fix xallocx(..., MALLOCX_ZERO) bugs.
Zero all trailing bytes of large allocations when
--enable-cache-oblivious configure option is enabled.  This regression
was introduced by 8a03cf039c (Implement
cache index randomization for large allocations.).

Zero trailing bytes of huge allocations when resizing from/to a size
class that is not a multiple of the chunk size.
2015-09-24 16:38:45 -07:00
Jason Evans
708ed79834 Resolve an unsupported special case in arena_prof_tctx_set().
Add arena_prof_tctx_reset() and use it instead of arena_prof_tctx_set()
when resetting the tctx pointer during reallocation, which happens
whenever an originally sampled reallocated object is not sampled during
reallocation.

This regression was introduced by
594c759f37 (Optimize
arena_prof_tctx_set().)
2015-09-14 23:57:58 -07:00
Jason Evans
560a4e1e01 Fix xallocx() bugs.
Fix xallocx() bugs related to the 'extra' parameter when specified as
non-zero.
2015-09-11 20:40:34 -07:00
Mike Hommey
4a2a3c9a6e Don't purge junk filled chunks when shrinking huge allocations
When junk filling is enabled, shrinking an allocation fills the bytes
that were previously allocated but now aren't. Purging the chunk before
doing that is just a waste of time.

This resolves #260.
2015-08-27 22:00:09 -07:00
Mike Hommey
6d8075f1e6 Fix chunk purge hook calls for in-place huge shrinking reallocation.
Fix chunk purge hook calls for in-place huge shrinking reallocation to
specify the old chunk size rather than the new chunk size.  This bug
caused no correctness issues for the default chunk purge function, but
was visible to custom functions set via the "arena.<i>.chunk_hooks"
mallctl.

This resolves #264.
2015-08-27 20:32:57 -07:00
Jason Evans
8fadb1a8c2 Implement chunk hook support for page run commit/decommit.
Cascade from decommit to purge when purging unused dirty pages, so that
it is possible to decommit cleaned memory rather than just purging.  For
non-Windows debug builds, decommit runs rather than purging them, since
this causes access of deallocated runs to segfault.

This resolves #251.
2015-08-07 00:50:58 -07:00
Jason Evans
b49a334a64 Generalize chunk management hooks.
Add the "arena.<i>.chunk_hooks" mallctl, which replaces and expands on
the "arena.<i>.chunk.{alloc,dalloc,purge}" mallctls.  The chunk hooks
allow control over chunk allocation/deallocation, decommit/commit,
purging, and splitting/merging, such that the application can rely on
jemalloc's internal chunk caching and retaining functionality, yet
implement a variety of chunk management mechanisms and policies.

Merge the chunks_[sz]ad_{mmap,dss} red-black trees into
chunks_[sz]ad_retained.  This slightly reduces how hard jemalloc tries
to honor the dss precedence setting; prior to this change the precedence
setting was also consulted when recycling chunks.

Fix chunk purging.  Don't purge chunks in arena_purge_stashed(); instead
deallocate them in arena_unstash_purged(), so that the dirty memory
linkage remains valid until after the last time it is used.

This resolves #176 and #201.
2015-08-03 21:49:02 -07:00
Jason Evans
d059b9d6a1 Implement support for non-coalescing maps on MinGW.
- Do not reallocate huge objects in place if the number of backing
  chunks would change.
- Do not cache multi-chunk mappings.

This resolves #213.
2015-07-24 18:39:14 -07:00
Jason Evans
40cbd30d50 Fix huge_ralloc_no_move() to succeed more often.
Fix huge_ralloc_no_move() to succeed if an allocation request results in
the same usable size as the existing allocation, even if the request
size is smaller than the usable size.  This bug did not cause
correctness issues, but it could cause unnecessary moves during
reallocation.
2015-07-24 18:20:48 -07:00
Jason Evans
87ccb55547 Fix huge_palloc() to handle size rather than usize input.
huge_ralloc() passes a size that may not be precisely a size class, so
make huge_palloc() handle the more general case of a size input rather
than usize.

This regression appears to have been introduced by the addition of
in-place huge reallocation; as such it was never incorporated into a
release.
2015-07-23 17:18:49 -07:00
Jason Evans
fd5f9e43c3 Avoid atomic operations for dependent rtree reads. 2015-05-15 17:02:30 -07:00
Jason Evans
65db63cf3f Fix in-place shrinking huge reallocation purging bugs.
Fix the shrinking case of huge_ralloc_no_move_similar() to purge the
correct number of pages, at the correct offset.  This regression was
introduced by 8d6a3e8321 (Implement
dynamic per arena control over dirty page purging.).

Fix huge_ralloc_no_move_shrink() to purge the correct number of pages.
This bug was introduced by 9673983443
(Purge/zero sub-chunk huge allocations as necessary.).
2015-03-25 19:10:06 -07:00
Jason Evans
8d6a3e8321 Implement dynamic per arena control over dirty page purging.
Add mallctls:
- arenas.lg_dirty_mult is initialized via opt.lg_dirty_mult, and can be
  modified to change the initial lg_dirty_mult setting for newly created
  arenas.
- arena.<i>.lg_dirty_mult controls an individual arena's dirty page
  purging threshold, and synchronously triggers any purging that may be
  necessary to maintain the constraint.
- arena.<i>.chunk.purge allows the per arena dirty page purging function
  to be replaced.

This resolves #93.
2015-03-18 18:55:33 -07:00
Jason Evans
a4e1888d1a Simplify extent_node_t and add extent_node_init(). 2015-02-17 15:13:52 -08:00
Jason Evans
ee41ad409a Integrate whole chunks into unused dirty page purging machinery.
Extend per arena unused dirty page purging to manage unused dirty chunks
in aaddtion to unused dirty runs.  Rather than immediately unmapping
deallocated chunks (or purging them in the --disable-munmap case), store
them in a separate set of trees, chunks_[sz]ad_dirty.  Preferrentially
allocate dirty chunks.  When excessive unused dirty pages accumulate,
purge runs and chunks in ingegrated LRU order (and unmap chunks in the
--enable-munmap case).

Refactor extent_node_t to provide accessor functions.
2015-02-16 21:02:17 -08:00
Jason Evans
2195ba4e1f Normalize *_link and link_* fields to all be *_link. 2015-02-15 16:43:52 -08:00
Jason Evans
cbf3a6d703 Move centralized chunk management into arenas.
Migrate all centralized data structures related to huge allocations and
recyclable chunks into arena_t, so that each arena can manage huge
allocations and recyclable virtual memory completely independently of
other arenas.

Add chunk node caching to arenas, in order to avoid contention on the
base allocator.

Use chunks_rtree to look up huge allocations rather than a red-black
tree.  Maintain a per arena unsorted list of huge allocations (which
will be needed to enumerate huge allocations during arena reset).

Remove the --enable-ivsalloc option, make ivsalloc() always available,
and use it for size queries if --enable-debug is enabled.  The only
practical implications to this removal are that 1) ivsalloc() is now
always available during live debugging (and the underlying radix tree is
available during core-based debugging), and 2) size query validation can
no longer be enabled independent of --enable-debug.

Remove the stats.chunks.{current,total,high} mallctls, and replace their
underlying statistics with simpler atomically updated counters used
exclusively for gdump triggering.  These statistics are no longer very
useful because each arena manages chunks independently, and per arena
statistics provide similar information.

Simplify chunk synchronization code, now that base chunk allocation
cannot cause recursive lock acquisition.
2015-02-12 00:15:56 -08:00
Jason Evans
1cb181ed63 Implement explicit tcache support.
Add the MALLOCX_TCACHE() and MALLOCX_TCACHE_NONE macros, which can be
used in conjunction with the *allocx() API.

Add the tcache.create, tcache.flush, and tcache.destroy mallctls.

This resolves #145.
2015-02-09 17:44:48 -08:00
Sébastien Marie
eee27b2a38 huge_node_locked don't have to unlock huge_mtx
in src/huge.c, after each call of huge_node_locked(), huge_mtx is
already unlocked. don't unlock it twice (it is a undefined behaviour).
2015-01-25 15:12:28 +01:00
Jason Evans
4581b97809 Implement metadata statistics.
There are three categories of metadata:

- Base allocations are used for bootstrap-sensitive internal allocator
  data structures.
- Arena chunk headers comprise pages which track the states of the
  non-metadata pages.
- Internal allocations differ from application-originated allocations
  in that they are for internal use, and that they are omitted from heap
  profiles.

The metadata statistics comprise the metadata categories as follows:

- stats.metadata: All metadata -- base + arena chunk headers + internal
  allocations.
- stats.arenas.<i>.metadata.mapped: Arena chunk headers.
- stats.arenas.<i>.metadata.allocated: Internal allocations.  This is
  reported separately from the other metadata statistics because it
  overlaps with the allocated and active statistics, whereas the other
  metadata statistics do not.

Base allocations are not reported separately, though their magnitude can
be computed by subtracting the arena-specific metadata.

This resolves #163.
2015-01-23 23:34:43 -08:00
Guilherme Goncalves
2c5cb613df Introduce two new modes of junk filling: "alloc" and "free".
In addition to true/false, opt.junk can now be either "alloc" or "free",
giving applications the possibility of junking memory only on allocation
or deallocation.

This resolves #172.
2014-12-14 17:07:26 -08:00
Jason Evans
1036ddbf11 Fix OOM cleanup in huge_palloc().
Fix OOM cleanup in huge_palloc() to call idalloct() rather than
base_node_dalloc().  This bug is a result of incomplete refactoring, and
has no impact other than leaking memory during OOM.
2014-12-04 16:42:42 -08:00
Jason Evans
2012d5a560 Fix pointer arithmetic undefined behavior.
Reported by Denis Denisov.
2014-11-17 09:54:49 -08:00
Daniel Micay
a9ea10d27c use sized deallocation internally for ralloc
The size of the source allocation is known at this point, so reading the
chunk header can be avoided for the small size class fast path. This is
not very useful right now, but it provides a significant performance
boost with an alternate ralloc entry point taking the old size.
2014-10-16 15:39:59 -04:00
Jason Evans
9673983443 Purge/zero sub-chunk huge allocations as necessary.
Purge trailing pages during shrinking huge reallocation when resulting
size is not a multiple of the chunk size.  Similarly, zero pages if
necessary during growing huge reallocation when the resulting size is
not a multiple of the chunk size.
2014-10-15 18:02:02 -07:00
Jason Evans
9b41ac909f Fix huge allocation statistics. 2014-10-14 22:20:00 -07:00
Jason Evans
3c4d92e82a Add per size class huge allocation statistics.
Add per size class huge allocation statistics, and normalize various
stats:
- Change the arenas.nlruns type from size_t to unsigned.
- Add the arenas.nhchunks and arenas.hchunks.<i>.size mallctl's.
- Replace the stats.arenas.<i>.bins.<j>.allocated mallctl with
  stats.arenas.<i>.bins.<j>.curregs .
- Add the stats.arenas.<i>.hchunks.<j>.nmalloc,
  stats.arenas.<i>.hchunks.<j>.ndalloc,
  stats.arenas.<i>.hchunks.<j>.nrequests, and
  stats.arenas.<i>.hchunks.<j>.curhchunks mallctl's.
2014-10-12 23:02:10 -07:00
Jason Evans
fc0b3b7383 Add configure options.
Add:
  --with-lg-page
  --with-lg-page-sizes
  --with-lg-size-class-group
  --with-lg-quantum

Get rid of STATIC_PAGE_SHIFT, in favor of directly setting LG_PAGE.

Fix various edge conditions exposed by the configure options.
2014-10-09 22:44:37 -07:00
Daniel Micay
f22214a29d Use regular arena allocation for huge tree nodes.
This avoids grabbing the base mutex, as a step towards fine-grained
locking for huge allocations. The thread cache also provides a tiny
(~3%) improvement for serial huge allocations.
2014-10-07 23:57:09 -07:00
Jason Evans
8bb3198f72 Refactor/fix arenas manipulation.
Abstract arenas access to use arena_get() (or a0get() where appropriate)
rather than directly reading e.g. arenas[ind].  Prior to the addition of
the arenas.extend mallctl, the worst possible outcome of directly
accessing arenas was a stale read, but arenas.extend may allocate and
assign a new array to arenas.

Add a tsd-based arenas_cache, which amortizes arenas reads.  This
introduces some subtle bootstrapping issues, with tsd_boot() now being
split into tsd_boot[01]() to support tsd wrapper allocation
bootstrapping, as well as an arenas_cache_bypass tsd variable which
dynamically terminates allocation of arenas_cache itself.

Promote a0malloc(), a0calloc(), and a0free() to be generally useful for
internal allocation, and use them in several places (more may be
appropriate).

Abstract arena->nthreads management and fix a missing decrement during
thread destruction (recent tsd refactoring left arenas_cleanup()
unused).

Change arena_choose() to propagate OOM, and handle OOM in all callers.
This is important for providing consistent allocation behavior when the
MALLOCX_ARENA() flag is being used.  Prior to this fix, it was possible
for an OOM to result in allocation silently allocating from a different
arena than the one specified.
2014-10-07 23:14:57 -07:00
Jason Evans
155bfa7da1 Normalize size classes.
Normalize size classes to use the same number of size classes per size
doubling (currently hard coded to 4), across the intire range of size
classes.  Small size classes already used this spacing, but in order to
support this change, additional small size classes now fill [4 KiB .. 16
KiB).  Large size classes range from [16 KiB .. 4 MiB).  Huge size
classes now support non-multiples of the chunk size in order to fill (4
MiB .. 16 MiB).
2014-10-06 01:45:13 -07:00
Daniel Micay
a95018ee81 Attempt to expand huge allocations in-place.
This adds support for expanding huge allocations in-place by requesting
memory at a specific address from the chunk allocator.

It's currently only implemented for the chunk recycling path, although
in theory it could also be done by optimistically allocating new chunks.
On Linux, it could attempt an in-place mremap. However, that won't work
in practice since the heap is grown downwards and memory is not unmapped
(in a normal build, at least).

Repeated vector reallocation micro-benchmark:

    #include <string.h>
    #include <stdlib.h>

    int main(void) {
        for (size_t i = 0; i < 100; i++) {
            void *ptr = NULL;
            size_t old_size = 0;
            for (size_t size = 4; size < (1 << 30); size *= 2) {
                ptr = realloc(ptr, size);
                if (!ptr) return 1;
                memset(ptr + old_size, 0xff, size - old_size);
                old_size = size;
            }
            free(ptr);
        }
    }

The glibc allocator fails to do any in-place reallocations on this
benchmark once it passes the M_MMAP_THRESHOLD (default 128k) but it
elides the cost of copies via mremap, which is currently not something
that jemalloc can use.

With this improvement, jemalloc still fails to do any in-place huge
reallocations for the first outer loop, but then succeeds 100% of the
time for the remaining 99 iterations. The time spent doing allocations
and copies drops down to under 5%, with nearly all of it spent doing
purging + faulting (when huge pages are disabled) and the array memset.

An improved mremap API (MREMAP_RETAIN - #138) would be far more general
but this is a portable optimization and would still be useful on Linux
for xallocx.

Numbers with transparent huge pages enabled:

glibc (copies elided via MREMAP_MAYMOVE): 8.471s

jemalloc: 17.816s
jemalloc + no-op madvise: 13.236s

jemalloc + this commit: 6.787s
jemalloc + this commit + no-op madvise: 6.144s

Numbers with transparent huge pages disabled:

glibc (copies elided via MREMAP_MAYMOVE): 15.403s

jemalloc: 39.456s
jemalloc + no-op madvise: 12.768s

jemalloc + this commit: 15.534s
jemalloc + this commit + no-op madvise: 6.354s

Closes #137
2014-10-05 14:47:01 -07:00
Jason Evans
551ebc4364 Convert to uniform style: cond == false --> !cond 2014-10-03 10:16:09 -07:00
Daniel Micay
f8034540a1 Implement in-place huge allocation shrinking.
Trivial example:

    #include <stdlib.h>

    int main(void) {
        void *ptr = malloc(1024 * 1024 * 8);
        if (!ptr) return 1;
        ptr = realloc(ptr, 1024 * 1024 * 4);
        if (!ptr) return 1;
    }

Before:

    mmap(NULL, 8388608, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcfff000000
    mmap(NULL, 4194304, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fcffec00000
    madvise(0x7fcfff000000, 8388608, MADV_DONTNEED) = 0

After:

    mmap(NULL, 8388608, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f1934800000
    madvise(0x7f1934c00000, 4194304, MADV_DONTNEED) = 0

Closes #134
2014-10-01 16:55:03 -07:00
Jason Evans
5460aa6f66 Convert all tsd variables to reside in a single tsd structure. 2014-09-23 02:36:08 -07:00
Jason Evans
9c640bfdd4 Apply likely()/unlikely() to allocation/deallocation fast paths. 2014-09-11 17:01:58 -07:00
Jason Evans
b718cf77e9 Optimize [nmd]alloc() fast paths.
Optimize [nmd]alloc() fast paths such that the (flags == 0) case is
streamlined, flags decoding only happens to the minimum degree
necessary, and no conditionals are repeated.
2014-09-07 14:40:19 -07:00