Commit Graph

191 Commits

Author SHA1 Message Date
Jasmin Parent
41a859ef73 Remove duplicated words in documentation 2022-07-11 15:30:16 -07:00
Qi Wang
8cb814629a Make the default option of zero realloc match the system allocator. 2022-05-05 17:11:18 -07:00
Qi Wang
254b011915 Small doc tweak of opt.trust_madvise.
Avoid quoted enabled and disabled because it's a bool type instead of char *.
2022-04-28 21:16:25 -07:00
Qi Wang
f5e840bbf0 Minor typo fix in doc. 2022-04-27 20:25:29 -07:00
Qi Wang
ceca07d2ca Correct the name of stats.mutexes.prof_thds_data in doc. 2022-04-25 20:12:58 -07:00
cuishuang
9a242f16d9 fix some typos
Signed-off-by: cuishuang <imcusg@gmail.com>
2022-04-25 11:29:00 -07:00
Qi Wang
0e29ad4efa Rename zero_realloc option "strict" to "alloc".
With realloc(ptr, 0) being UB per C23, the option name "strict" makes less sense
now.  Rename to "alloc" which describes the behavior.
2022-04-20 10:27:25 -07:00
yunxu
b798fabdf7 Add prof_leak_error option
The option makes the process to exit with error code 1 if a memory leak
is detected. This is useful for implementing automated tools that rely
on leak detection.
2022-01-21 16:24:20 -08:00
Alex Lapenkou
3b3257a709 Correct opt.prof_leak documentation
The option has been misleading, because it stays disabled unless
prof_final is also specified. In practice it's impossible to detect that
the option is silently disabled, because it just doesn't provide any
output as if there are no memory leaks detected.
2021-11-23 15:10:21 -08:00
Qi Wang
5884a076fb Rename prof.dump_prefix to prof.prefix
This better aligns with our naming convention.  The option has not been included
in any upstream release yet.
2021-08-12 23:04:29 -07:00
lirui
2ae1ef7dbd Fix doc large size 54 KiB error 2021-03-26 13:34:49 -07:00
Qi Wang
a11be50332 Implement opt.cache_oblivious.
Keep config.cache_oblivious for now to remain backward-compatible.
2021-02-11 11:32:01 -08:00
Azat Khuzhin
a943172b73 Add runtime detection for MADV_DONTNEED zeroes pages (mostly for qemu)
qemu does not support this, yet [1], and you can get very tricky assert
if you will run program with jemalloc in use under qemu:

    <jemalloc>: ../contrib/jemalloc/src/extent.c:1195: Failed assertion: "p[i] == 0"

  [1]: https://patchwork.kernel.org/patch/10576637/

Here is a simple example that shows the problem [2]:

    // Gist to check possible issues with MADV_DONTNEED
    // For example it does not supported by qemu user
    // There is a patch for this [1], but it hasn't been applied.
    //   [1]: https://lists.gnu.org/archive/html/qemu-devel/2018-08/msg05422.html

    #include <sys/mman.h>
    #include <stdio.h>
    #include <stddef.h>
    #include <assert.h>
    #include <string.h>

    int main(int argc, char **argv)
    {
        void *addr = mmap(NULL, 1<<16, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
        if (addr == MAP_FAILED) {
            perror("mmap");
            return 1;
        }
        memset(addr, 'A', 1<<16);

        if (!madvise(addr, 1<<16, MADV_DONTNEED)) {
            puts("MADV_DONTNEED does not return error. Check memory.");
            for (int i = 0; i < 1<<16; ++i) {
                assert(((unsigned char *)addr)[i] == 0);
            }
        } else {
            perror("madvise");
        }

        if (munmap(addr, 1<<16)) {
            perror("munmap");
            return 1;
        }

        return 0;
    }

  ### unpatched qemu

      $ qemu-x86_64-static /tmp/test-MADV_DONTNEED
      MADV_DONTNEED does not return error. Check memory.
      test-MADV_DONTNEED: /tmp/test-MADV_DONTNEED.c:19: main: Assertion `((unsigned char *)addr)[i] == 0' failed.
      qemu: uncaught target signal 6 (Aborted) - core dumped
      Aborted (core dumped)

  ### patched qemu (by returning ENOSYS error)

      $ qemu-x86_64 /tmp/test-MADV_DONTNEED
      madvise: Success

  ### patch for qemu to return ENOSYS

      diff --git a/linux-user/syscall.c b/linux-user/syscall.c
      index 897d20c076..5540792e0e 100644
      --- a/linux-user/syscall.c
      +++ b/linux-user/syscall.c
      @@ -11775,7 +11775,7 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
                  turns private file-backed mappings into anonymous mappings.
                  This will break MADV_DONTNEED.
                  This is a hint, so ignoring and returning success is ok.  */
      -        return 0;
      +        return ENOSYS;
       #endif
       #ifdef TARGET_NR_fcntl64
           case TARGET_NR_fcntl64:

  [2]: https://gist.github.com/azat/12ba2c825b710653ece34dba7f926ece

v2:
- review fixes
- add opt_dont_trust_madvise
v3:
- review fixes
- rename opt_dont_trust_madvise to opt_trust_madvise
2021-01-20 20:08:30 -08:00
Qi Wang
bf72188f80 Allow opt.tcache_max to accept small size classes.
Previously all the small size classes were cached.  However this has downsides
-- particularly when page size is greater than 4K (e.g. iOS), which will result
in much higher SMALL_MAXCLASS.

This change allows tcache_max to be set to lower values, to better control
resources taken by tcache.
2020-10-24 20:43:44 -07:00
Qi Wang
c8209150f9 Switch from opt.lg_tcache_max to opt.tcache_max
Though for convenience, keep parsing lg_tcache_max.
2020-10-22 20:40:41 -07:00
Qi Wang
5e41ff9b74 Add a hard limit on tcache max size class.
For locality reasons, tcache bins are integrated in TSD.  Allowing all size
classes to be cached has little benefit, but takes up much thread local storage.
In addition, it complicates the layout which we try hard to optimize.
2020-10-16 13:49:51 -07:00
Yinan Zhang
fb347dc618 Verify output space before doing heavy work in mallctl 2020-07-27 09:48:35 -07:00
Yinan Zhang
f5fb4e5a97 Modify mallctl output length when needed
This is the only reason why `oldlenp` was designed to be in the form
of a pointer.
2020-07-27 09:48:35 -07:00
Yinan Zhang
c8683bee80 Unify printing for prof counts object 2020-06-29 14:27:50 -07:00
David Goldblatt
d82a164d0d Add thread.peak.[read|reset] mallctls.
These can be used to track net allocator activity on a per-thread basis.
2020-06-11 13:54:22 -07:00
Qi Wang
88b0e03a4e Implement opt.stats_interval and the _opts options.
Add options stats_interval and stats_interval_opts to allow interval based stats
printing.  This provides an easy way to collect stats without code changes,
because opt.stats_print may not work (some binaries never exit).
2020-01-29 09:57:55 -08:00
Qi Wang
ea351a7b52 Fix syntax errors in doc for thread.idle. 2020-01-23 16:41:53 -08:00
David Goldblatt
6a622867ca Add "thread.idle" mallctl.
This can encapsulate various internal cleaning logic, and can be used to free up
resources before a long sleep.
2020-01-22 18:29:13 -08:00
Qi Wang
e4c36a6f30 Emphasize no modification through thread.allocatedp allowed. 2019-11-13 09:12:08 -08:00
David T. Goldblatt
de81a4eada Add stats counters for number of zero reallocs 2019-10-29 17:48:44 -07:00
David T. Goldblatt
9cfa805947 Realloc: Make behavior of realloc(ptr, 0) configurable. 2019-10-29 17:48:44 -07:00
zhxchen17
4b76c684bb Add "prof.dump_prefix" to override filename prefixes for dumps. 2019-09-12 22:26:03 -07:00
Yinan Zhang
39343555d6 Report stats for tdatas_mtx and prof_dump_mtx 2019-08-09 09:24:16 -07:00
Qi Wang
9f6a9f4c1f Update manual for opt.retain (new default on Windows). 2019-07-25 15:25:58 -07:00
Yinan Zhang
d26636d566 Fix logic in printing
`cbopaque` can now be overriden without overriding `write_cb` in
the first place.  (Otherwise there would be no need to have the
`cbopaque` parameter in `malloc_message`.)
2019-07-16 14:54:23 -07:00
Yinan Zhang
c92ac30601 Add confirm_conf option
If the confirm_conf option is set, when the program starts, each of
the four malloc_conf strings will be printed, and each option will
be printed when being set.
2019-05-22 09:38:39 -07:00
Qi Wang
07c44847c2 Track nfills and nflushes for arenas.i.small / large.
Small is added purely for convenience.  Large flushes wasn't tracked before and
can be useful in analysis.  Large fill simply reports nmalloc, since there is no
batch fill for large currently.
2019-05-15 10:05:09 -07:00
Doron Roberts-Kedes
7fc4f2a32c Add nonfull_slabs to bin_stats_t.
When config_stats is enabled track the size of bin->slabs_nonfull in
the new nonfull_slabs counter in bin_stats_t. This metric should be
useful for establishing an upper ceiling on the savings possible by
meshing.
2019-04-29 13:35:02 -07:00
Qi Wang
064d6e570e Tweak the wording about oversize_threshold. 2019-04-01 10:36:29 -07:00
Qi Wang
ce03e4c7b8 Document opt.oversize_threshold. 2019-03-29 11:55:05 -07:00
Qi Wang
e3db480f6f Rename huge_threshold to oversize_threshold.
The keyword huge tend to remind people of huge pages which is not relevent to
the feature.
2019-01-25 13:15:45 -08:00
Edward Tomasz Napierala
a7b0a124c3 Mention different mmap(2) behaviour with retain:true. 2019-01-23 18:34:59 -08:00
Tyler Etzel
126252a7e6 Add stats for the size of extent_avail heap 2018-08-02 10:16:06 -07:00
Tyler Etzel
c14e6c0819 Add extents information to mallocstats output
- Show number/bytes of extents of each size that are dirty, muzzy, retained.
2018-08-02 10:16:06 -07:00
Qi Wang
cdf15b458a Rename huge_threshold to experimental, and tweak documentation. 2018-06-29 10:35:02 -07:00
Latchesar Ionkov
a32b7bd567 Mallctl: Add arenas.lookup
Implement a new mallctl operation that allows looking up the arena a
region of memory belongs to.
2018-05-01 13:14:36 -07:00
Qi Wang
02585420c3 Document liveness requirements for extent_hooks_t structures. 2018-04-11 12:35:28 -07:00
Dave Watson
8b14f3abc0 background_thread: add max thread count config
Looking at the thread counts in our services, jemalloc's background thread
is useful, but mostly idle.  Add a config option to tune down the number of threads.
2018-04-10 14:01:45 -07:00
Qi Wang
e4f090e8df Add opt.thp which allows explicit hugepage usage.
"always" marks all user mappings as MADV_HUGEPAGE; while "never" marks all
mappings as MADV_NOHUGEPAGE. The default setting "default" does not change any
settings.  Note that all the madvise calls are part of the default extent hooks
by design, so that customized extent hooks have complete control over the
mappings including hugepage settings.
2018-03-08 13:08:06 -08:00
Qi Wang
efa40532dc Remove config.thp which wasn't in use. 2018-03-08 13:08:06 -08:00
Qi Wang
fac706836f Add opt.lg_extent_max_active_fit
When allocating from dirty extents (which we always prefer if available), large
active extents can get split even if the new allocation is much smaller, in
which case the introduced fragmentation causes high long term damage.  This new
option controls the threshold to reuse and split an existing active extent.  We
avoid using a large extent for much smaller sizes, in order to reduce
fragmentation.  In some workload, adding the threshold improves virtual memory
usage by >10x.
2017-11-16 15:32:02 -08:00
Qi Wang
e422fa8e7e Add arena.i.retain_grow_limit
This option controls the max size when grow_retained.  This is useful when we
have customized extent hooks reserving physical memory (e.g. 1G huge pages).
Without this feature, the default increasing sequence could result in fragmented
and wasted physical memory.
2017-11-03 13:53:33 -07:00
Qi Wang
fc83de0384 Document the potential issues about opt.background_thread. 2017-10-11 09:52:04 -07:00
Qi Wang
cf4738455d Fix a link for dirty_decay_ms in manual. 2017-09-11 13:38:45 -07:00
Qi Wang
e55c3ca267 Add stats for metadata_thp.
Report number of THPs used in arena and aggregated stats.
2017-08-30 16:47:32 -07:00