mdbx: отладка всплесков GC в Erigon.

mdbx.h

@@ -4111,6 +4111,12 @@ struct MDBX_commit_latency {
     /** \brief Количество страничных промахов (page faults) внутри GC
      *  при выделении и подготовки страниц для самой GC. */
     uint32_t self_majflt;
+    /* Для разборок с pnl_merge() */
+    struct {
+      uint32_t time;
+      uint64_t volume;
+      uint32_t calls;
+    } pnl_merge_work, pnl_merge_self;
   } gc_prof;
 };
 #ifndef __cplusplus

src/core.c

@@ -8004,7 +8004,15 @@ next_gc:;
   }
 
   /* Merge in descending sorted order */
+#if MDBX_ENABLE_PROFGC
+  const uint64_t merge_begin = osal_monotime();
+#endif /* MDBX_ENABLE_PROFGC */
   pnl_merge(txn->tw.relist, gc_pnl);
+#if MDBX_ENABLE_PROFGC
+  prof->pnl_merge.calls += 1;
+  prof->pnl_merge.volume += MDBX_PNL_GETSIZE(txn->tw.relist);
+  prof->pnl_merge.time += osal_monotime() - merge_begin;
+#endif /* MDBX_ENABLE_PROFGC */
   flags |= MDBX_ALLOC_SHOULD_SCAN;
   if (AUDIT_ENABLED()) {
     if (unlikely(!pnl_check(txn->tw.relist, txn->mt_next_pgno))) {
@@ -12084,6 +12092,16 @@ static void take_gcprof(MDBX_txn *txn, MDBX_commit_latency *latency) {
     latency->gc_prof.wipes = ptr->gc_prof.wipes;
     latency->gc_prof.flushes = ptr->gc_prof.flushes;
     latency->gc_prof.kicks = ptr->gc_prof.kicks;
+
+    latency->gc_prof.pnl_merge_work.time =
+        osal_monotime_to_16dot16(ptr->gc_prof.work.pnl_merge.time);
+    latency->gc_prof.pnl_merge_work.calls = ptr->gc_prof.work.pnl_merge.calls;
+    latency->gc_prof.pnl_merge_work.volume = ptr->gc_prof.work.pnl_merge.volume;
+    latency->gc_prof.pnl_merge_self.time =
+        osal_monotime_to_16dot16(ptr->gc_prof.self.pnl_merge.time);
+    latency->gc_prof.pnl_merge_self.calls = ptr->gc_prof.self.pnl_merge.calls;
+    latency->gc_prof.pnl_merge_self.volume = ptr->gc_prof.self.pnl_merge.volume;
+
     if (txn == env->me_txn0)
       memset(&ptr->gc_prof, 0, sizeof(ptr->gc_prof));
   } else

src/internals.h

@@ -756,6 +756,12 @@ typedef struct profgc_stat {
   uint32_t spe_counter;
   /* page faults (hard page faults) */
   uint32_t majflt;
+  /* Для разборок с pnl_merge() */
+  struct {
+    uint64_t time;
+    uint64_t volume;
+    uint32_t calls;
+  } pnl_merge;
 } profgc_stat_t;
 
 /* Statistics of page operations overall of all (running, completed and aborted)

src/options.h

@@ -89,7 +89,7 @@
 
 /** Controls profiling of GC search and updates. */
 #ifndef MDBX_ENABLE_PROFGC
-#define MDBX_ENABLE_PROFGC 0
+#define MDBX_ENABLE_PROFGC 1
 #elif !(MDBX_ENABLE_PROFGC == 0 || MDBX_ENABLE_PROFGC == 1)
 #error MDBX_ENABLE_PROFGC must be defined as 0 or 1
 #endif /* MDBX_ENABLE_PROFGC */