Improve accounting a bit more

src/gc-debug.c

@@ -1230,10 +1230,10 @@ void _report_gc_finished(uint64_t pause, uint64_t freed, int full, int recollect
  recollect ? "recollect" : ""
  );
 
- jl_safe_printf("Heap stats: bytes_mapped %.2f MB, bytes_resident %.2f MB, live_bytes %.2f MB,\nheap_size %.2f MB, heap_target %.2f MB, Fragmentation %.3f\n",
+ jl_safe_printf("Heap stats: bytes_mapped %.2f MB, bytes_resident %.2f MB,\nheap_size %.2f MB, heap_target %.2f MB, Fragmentation %.3f\n",
  jl_atomic_load_relaxed(&gc_heap_stats.bytes_mapped)/(double)(1<<20),
  jl_atomic_load_relaxed(&gc_heap_stats.bytes_resident)/(double)(1<<20),
- live_bytes/(double)(1<<20),
+ // live_bytes/(double)(1<<20), live byes tracking is not accurate.
  jl_atomic_load_relaxed(&gc_heap_stats.heap_size)/(double)(1<<20),
  jl_atomic_load_relaxed(&gc_heap_stats.heap_target)/(double)(1<<20),
  (double)live_bytes/(double)jl_atomic_load_relaxed(&gc_heap_stats.heap_size)

src/gc.c

@@ -697,7 +697,7 @@ static uint64_t old_heap_size = 0;
 static uint64_t old_alloc_diff = 0;
 static uint64_t old_freed_diff = 0;
 static uint64_t gc_end_time = 0;
-
+static int thrash_counter = 0;
 
 // global variables for GC stats
 
@@ -3324,7 +3324,7 @@ static int _jl_gc_collect(jl_ptls_t ptls, jl_gc_collection_t collection)
  gc_num.last_incremental_sweep = gc_end_time;
  }
 
- int thrashing = 0; // maybe we should report this to the user or error out?
+ int thrashing = thrash_counter > 4; // maybe we should report this to the user or error out?
  size_t heap_size = jl_atomic_load_relaxed(&gc_heap_stats.heap_size);
  double target_allocs = 0.0;
  double min_interval = default_collect_interval;
@@ -3343,7 +3343,10 @@ static int _jl_gc_collect(jl_ptls_t ptls, jl_gc_collection_t collection)
  old_freed_diff = freed_diff;
  old_pause_time = pause;
  old_heap_size = heap_size; // TODO: Update these values dynamically instead of just during the GC
- thrashing = gc_time > mutator_time * 98 ? 1 : 0;
+ if (gc_time > alloc_time * 95)
+ thrash_counter += 1;
+ else
+ thrash_counter = 0;
  if (alloc_mem != 0 && alloc_time != 0 && gc_mem != 0 && gc_time != 0 ) {
  double alloc_rate = alloc_mem/alloc_time;
  double gc_rate = gc_mem/gc_time;
@@ -3723,6 +3726,26 @@ JL_DLLEXPORT void *jl_gc_counted_realloc_with_old_size(void *p, size_t old, size
  jl_atomic_store_relaxed(&ptls->gc_num.realloc,
  jl_atomic_load_relaxed(&ptls->gc_num.realloc) + 1);
  jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, sz-old);
+
+ int64_t diff = sz - old;
+ if (diff < 0) {
+ uint64_t free_acc = jl_atomic_load_relaxed(&ptls->gc_num.free_acc);
+ if (free_acc + diff < 16*1024)
+ jl_atomic_store_relaxed(&ptls->gc_num.free_acc, free_acc + sz);
+ else {
+ jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, -(free_acc + sz));
+ jl_atomic_store_relaxed(&ptls->gc_num.free_acc, 0);
+ }
+ }
+ else {
+ uint64_t alloc_acc = jl_atomic_load_relaxed(&ptls->gc_num.alloc_acc);
+ if (alloc_acc + diff < 16*1024)
+ jl_atomic_store_relaxed(&ptls->gc_num.alloc_acc, alloc_acc + diff);
+ else {
+ jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, alloc_acc + diff);
+ jl_atomic_store_relaxed(&ptls->gc_num.alloc_acc, 0);
+ }
+ }
  }
  return realloc(p, sz);
 }
@@ -3839,6 +3862,27 @@ static void *gc_managed_realloc_(jl_ptls_t ptls, void *d, size_t sz, size_t olds
  jl_atomic_load_relaxed(&ptls->gc_num.allocd) + (allocsz - oldsz));
  jl_atomic_store_relaxed(&ptls->gc_num.realloc,
  jl_atomic_load_relaxed(&ptls->gc_num.realloc) + 1);
+
+ int64_t diff = allocsz - oldsz;
+ if (diff < 0) {
+ uint64_t free_acc = jl_atomic_load_relaxed(&ptls->gc_num.free_acc);
+ if (free_acc + diff < 16*1024)
+ jl_atomic_store_relaxed(&ptls->gc_num.free_acc, free_acc + sz);
+ else {
+ jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, -(free_acc + sz));
+ jl_atomic_store_relaxed(&ptls->gc_num.free_acc, 0);
+ }
+ }
+ else {
+ uint64_t alloc_acc = jl_atomic_load_relaxed(&ptls->gc_num.alloc_acc);
+ if (alloc_acc + diff < 16*1024)
+ jl_atomic_store_relaxed(&ptls->gc_num.alloc_acc, alloc_acc + diff);
+ else {
+ jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, alloc_acc + diff);
+ jl_atomic_store_relaxed(&ptls->gc_num.alloc_acc, 0);
+ }
+ }
+
  jl_atomic_fetch_add_relaxed(&gc_heap_stats.heap_size, allocsz-oldsz);
  int last_errno = errno;
 #ifdef _OS_WINDOWS_