project-base/server-skynet-source-3rd-jemalloc
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Bypass extent_dalloc when retain is enabled.

Browse Source 
When retain is enabled, the default dalloc hook does nothing (since we avoid
munmap).  But the overhead preparing the call is high, specifically the extent
de-register and re-register involve locking and extent / rtree modifications.
Bypass the call with retain in this diff.
This commit is contained in:
Qi Wang 2018-10-31 14:54:53 -07:00 committed by Qi Wang
parent 50b473c883
commit 8dabf81df1
1 changed files with 18 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
src/extent.c
View File

@ -1695,6 +1695,12 @@ extent_dalloc_gap(tsdn_t *tsdn, arena_t *arena, extent_t *extent) {
extent_dalloc_wrapper(tsdn, arena, &extent_hooks, extent);
}
static bool
extent_may_dalloc(void) {
/* With retain enabled, the default dalloc always fails. */
return !opt_retain;
}
static bool
extent_dalloc_default_impl(void *addr, size_t size) {
if (!have_dss || !extent_in_dss(addr)) {
@ -1750,16 +1756,20 @@ extent_dalloc_wrapper(tsdn_t *tsdn, arena_t *arena,
witness_assert_depth_to_rank(tsdn_witness_tsdp_get(tsdn),
WITNESS_RANK_CORE, 0);
/*
* Deregister first to avoid a race with other allocating threads, and
* reregister if deallocation fails.
*/
extent_deregister(tsdn, extent);
if (!extent_dalloc_wrapper_try(tsdn, arena, r_extent_hooks, extent)) {
return;
/* Avoid calling the default extent_dalloc unless have to. */
if (*r_extent_hooks != &extent_hooks_default || extent_may_dalloc()) {
/*
* Deregister first to avoid a race with other allocating
* threads, and reregister if deallocation fails.
*/
extent_deregister(tsdn, extent);
if (!extent_dalloc_wrapper_try(tsdn, arena, r_extent_hooks,
extent)) {
return;
}
extent_reregister(tsdn, extent);
}
extent_reregister(tsdn, extent);
if (*r_extent_hooks != &extent_hooks_default) {
extent_hook_pre_reentrancy(tsdn, arena);
}