romenskiy2012/jemalloc
1
0
Fork 0
mirror of https://github.com/jemalloc/jemalloc.git synced 2026-06-03 10:44:16 +03:00
Code Issues Projects Releases Packages Wiki Activity

Introduce pinned extents to contain unpurgeable pages

Browse source 
Some pages (e.g., hugetlb pages) cannot be purged, and should be
prioritized for reuse.  A custom extent_alloc hook signals this by
OR'ing EXTENT_ALLOC_FLAG_PINNED into the low bits of the returned
pointer; jemalloc strips the flag bits and caches pinned extents in
a dedicated ecache_pinned, separate from the dirty/muzzy decay
pipeline.

Pinned extents do not coalesce eagerly, except for ones larger than
SC_LARGE_MINCLASS.  A prefer-small policy reuses the smallest fitting
pinned extent, to avoid unnecessary split/fragmentation.
This commit is contained in:
Bin Liu 2026-04-19 22:56:22 -07:00 • committed by Guangli Dai
parent 7638093c73
commit be2de8ccd8
22 changed files with 977 additions and 86 deletions
Download patch file Download diff file Expand all files Collapse all files

32
src/stats.c
View file

@ -712,6 +712,8 @@ stats_arena_extents_print(emitter_t *emitter, unsigned i) {
COL_HDR(row, muzzy, NULL, right, 13, size)
COL_HDR(row, nretained, NULL, right, 13, size)
COL_HDR(row, retained, NULL, right, 13, size)
COL_HDR(row, npinned, NULL, right, 13, size)
COL_HDR(row, pinned, NULL, right, 13, size)
COL_HDR(row, ntotal, NULL, right, 13, size)
COL_HDR(row, total, NULL, right, 13, size)
@ -728,22 +730,27 @@ stats_arena_extents_print(emitter_t *emitter, unsigned i) {
in_gap = false;
for (j = 0; j < SC_NPSIZES; j++) {
size_t ndirty, nmuzzy, nretained, total, dirty_bytes,
muzzy_bytes, retained_bytes, total_bytes;
size_t ndirty, nmuzzy, nretained, npinned, total,
dirty_bytes, muzzy_bytes, retained_bytes, pinned_bytes,
total_bytes;
stats_arenas_mib[4] = j;
CTL_LEAF(stats_arenas_mib, 5, "ndirty", &ndirty, size_t);
CTL_LEAF(stats_arenas_mib, 5, "nmuzzy", &nmuzzy, size_t);
CTL_LEAF(stats_arenas_mib, 5, "nretained", &nretained, size_t);
CTL_LEAF(stats_arenas_mib, 5, "npinned", &npinned, size_t);
CTL_LEAF(
stats_arenas_mib, 5, "dirty_bytes", &dirty_bytes, size_t);
CTL_LEAF(
stats_arenas_mib, 5, "muzzy_bytes", &muzzy_bytes, size_t);
CTL_LEAF(stats_arenas_mib, 5, "retained_bytes", &retained_bytes,
size_t);
CTL_LEAF(stats_arenas_mib, 5, "pinned_bytes", &pinned_bytes,
size_t);
total = ndirty + nmuzzy + nretained;
total_bytes = dirty_bytes + muzzy_bytes + retained_bytes;
total = ndirty + nmuzzy + nretained + npinned;
total_bytes = dirty_bytes + muzzy_bytes + retained_bytes
+ pinned_bytes;
in_gap_prev = in_gap;
in_gap = (total == 0);
@ -758,6 +765,8 @@ stats_arena_extents_print(emitter_t *emitter, unsigned i) {
emitter_json_kv(emitter, "nmuzzy", emitter_type_size, &nmuzzy);
emitter_json_kv(
emitter, "nretained", emitter_type_size, &nretained);
emitter_json_kv(
emitter, "npinned", emitter_type_size, &npinned);
emitter_json_kv(
emitter, "dirty_bytes", emitter_type_size, &dirty_bytes);
@ -765,6 +774,8 @@ stats_arena_extents_print(emitter_t *emitter, unsigned i) {
emitter, "muzzy_bytes", emitter_type_size, &muzzy_bytes);
emitter_json_kv(emitter, "retained_bytes", emitter_type_size,
&retained_bytes);
emitter_json_kv(emitter, "pinned_bytes", emitter_type_size,
&pinned_bytes);
emitter_json_object_end(emitter);
col_size.size_val = sz_pind2sz(j);
@ -775,6 +786,8 @@ stats_arena_extents_print(emitter_t *emitter, unsigned i) {
col_muzzy.size_val = muzzy_bytes;
col_nretained.size_val = nretained;
col_retained.size_val = retained_bytes;
col_npinned.size_val = npinned;
col_pinned.size_val = pinned_bytes;
col_ntotal.size_val = total;
col_total.size_val = total_bytes;
@ -1166,7 +1179,7 @@ stats_arena_print(emitter_t *emitter, unsigned i, bool bins, bool large,
unsigned nthreads;
const char *dss;
ssize_t dirty_decay_ms, muzzy_decay_ms;
size_t page, pactive, pdirty, pmuzzy, mapped, retained;
size_t page, pactive, pdirty, pmuzzy, mapped, retained, pinned;
size_t base, internal, resident, metadata_edata, metadata_rtree,
metadata_thp, extent_avail;
uint64_t dirty_npurge, dirty_nmadvise, dirty_purged;
@ -1467,6 +1480,7 @@ stats_arena_print(emitter_t *emitter, unsigned i, bool bins, bool large,
GET_AND_EMIT_MEM_STAT(mapped)
GET_AND_EMIT_MEM_STAT(retained)
GET_AND_EMIT_MEM_STAT(pinned)
GET_AND_EMIT_MEM_STAT(base)
GET_AND_EMIT_MEM_STAT(internal)
GET_AND_EMIT_MEM_STAT(metadata_edata)
@ -1872,7 +1886,7 @@ stats_print_helper(emitter_t *emitter, bool merged, bool destroyed,
* the transition to the emitter code.
*/
size_t allocated, active, metadata, metadata_edata, metadata_rtree,
metadata_thp, resident, mapped, retained;
metadata_thp, resident, mapped, retained, pinned;
size_t num_background_threads;
size_t zero_reallocs;
uint64_t background_thread_num_runs, background_thread_run_interval;
@ -1886,6 +1900,7 @@ stats_print_helper(emitter_t *emitter, bool merged, bool destroyed,
CTL_GET("stats.resident", &resident, size_t);
CTL_GET("stats.mapped", &mapped, size_t);
CTL_GET("stats.retained", &retained, size_t);
CTL_GET("stats.pinned", &pinned, size_t);
CTL_GET("stats.zero_reallocs", &zero_reallocs, size_t);
@ -1916,15 +1931,16 @@ stats_print_helper(emitter_t *emitter, bool merged, bool destroyed,
emitter_json_kv(emitter, "resident", emitter_type_size, &resident);
emitter_json_kv(emitter, "mapped", emitter_type_size, &mapped);
emitter_json_kv(emitter, "retained", emitter_type_size, &retained);
emitter_json_kv(emitter, "pinned", emitter_type_size, &pinned);
emitter_json_kv(
emitter, "zero_reallocs", emitter_type_size, &zero_reallocs);
emitter_table_printf(emitter,
"Allocated: %zu, active: %zu, "
"metadata: %zu (n_thp %zu, edata %zu, rtree %zu), resident: %zu, "
"mapped: %zu, retained: %zu\n",
"mapped: %zu, retained: %zu, pinned: %zu\n",
allocated, active, metadata, metadata_thp, metadata_edata,
metadata_rtree, resident, mapped, retained);
metadata_rtree, resident, mapped, retained, pinned);
/* Strange behaviors */
emitter_table_printf(emitter,