diff --git a/include/mimalloc/internal.h b/include/mimalloc/internal.h
index 9c5eb362..50bd5d79 100644
--- a/include/mimalloc/internal.h
+++ b/include/mimalloc/internal.h
@@ -219,6 +219,7 @@ void          _mi_page_free_collect_partly(mi_page_t* page, mi_block_t* head);
 void          _mi_page_init(mi_heap_t* heap, mi_page_t* page);
 bool          _mi_page_queue_is_valid(mi_heap_t* heap, const mi_page_queue_t* pq);
 
+size_t        _mi_page_bin(const mi_page_t* page); // for stats
 size_t        _mi_bin_size(size_t bin);            // for stats
 size_t        _mi_bin(size_t size);                // for stats
 
@@ -237,6 +238,7 @@ void          _mi_heap_page_reclaim(mi_heap_t* heap, mi_page_t* page);
 
 // "stats.c"
 void          _mi_stats_done(mi_stats_t* stats);
+void          _mi_stats_merge_thread(mi_tld_t* tld);
 void          _mi_stats_merge_from(mi_stats_t* to, mi_stats_t* from);
 mi_msecs_t    _mi_clock_now(void);
 mi_msecs_t    _mi_clock_end(mi_msecs_t start);
diff --git a/src/heap.c b/src/heap.c
index 971aad68..17dd1fdb 100644
--- a/src/heap.c
+++ b/src/heap.c
@@ -130,9 +130,7 @@ static void mi_heap_collect_ex(mi_heap_t* heap, mi_collect_t collect)
   _mi_arenas_collect(collect == MI_FORCE /* force purge? */, collect >= MI_FORCE /* visit all? */, heap->tld);
 
   // merge statistics
-  if (collect <= MI_FORCE) {
-    mi_stats_merge();
-  }
+  if (collect <= MI_FORCE) { _mi_stats_merge_thread(heap->tld); }
 }
 
 void _mi_heap_collect_abandon(mi_heap_t* heap) {
diff --git a/src/page-queue.c b/src/page-queue.c
index 3e2315cc..91bb0ef9 100644
--- a/src/page-queue.c
+++ b/src/page-queue.c
@@ -168,8 +168,7 @@ bool _mi_page_queue_is_valid(mi_heap_t* heap, const mi_page_queue_t* pq) {
   return true;
 }
 
-
-static size_t mi_page_bin(const mi_page_t* page) {
+size_t _mi_page_bin(const mi_page_t* page) {
   const size_t bin = (mi_page_is_in_full(page) ? MI_BIN_FULL : (mi_page_is_huge(page) ? MI_BIN_HUGE : mi_bin(mi_page_block_size(page))));
   mi_assert_internal(bin <= MI_BIN_FULL);
   return bin;
@@ -177,7 +176,7 @@ static size_t mi_page_bin(const mi_page_t* page) {
 
 static mi_page_queue_t* mi_heap_page_queue_of(mi_heap_t* heap, const mi_page_t* page) {
   mi_assert_internal(heap!=NULL);
-  const size_t bin = mi_page_bin(page);
+  const size_t bin = _mi_page_bin(page);
   mi_page_queue_t* pq = &heap->pages[bin];
   mi_assert_internal((mi_page_block_size(page) == pq->block_size) ||
                        (mi_page_is_huge(page) && mi_page_queue_is_huge(pq)) ||
diff --git a/src/page.c b/src/page.c
index 0d8e4e12..103d11b4 100644
--- a/src/page.c
+++ b/src/page.c
@@ -324,7 +324,7 @@ static mi_page_t* mi_page_fresh_alloc(mi_heap_t* heap, mi_page_queue_t* pq, size
   }
   mi_heap_stat_increase(heap, pages, 1);
   mi_assert_internal(pq!=NULL || mi_page_block_size(page) >= block_size);
-  mi_heap_stat_increase(heap, page_bins[mi_page_bin(page)], 1);
+  mi_heap_stat_increase(heap, page_bins[_mi_page_bin(page)], 1);
   mi_assert_expensive(_mi_page_is_valid(page));
   return page;
 }
@@ -395,7 +395,7 @@ void _mi_page_free(mi_page_t* page, mi_page_queue_t* pq) {
 
   // and free it
   mi_heap_t* heap = page->heap;
-  mi_heap_stat_decrease(heap, page_bins[mi_page_bin(page)], 1);
+  mi_heap_stat_decrease(heap, page_bins[_mi_page_bin(page)], 1);
   mi_heap_stat_decrease(heap, pages, 1);
   mi_page_set_heap(page,NULL);
   _mi_arenas_page_free(page);
diff --git a/src/stats.c b/src/stats.c
index 3b53d5a9..93b68054 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -406,6 +406,10 @@ void _mi_stats_merge_from(mi_stats_t* to, mi_stats_t* from) {
   }
 }
 
+void _mi_stats_merge_thread(mi_tld_t* tld) {
+  _mi_stats_merge_from( &tld->subproc->stats, &tld->stats );
+}
+
 void _mi_stats_done(mi_stats_t* stats) {  // called from `mi_thread_done`
   _mi_stats_merge_from(&_mi_subproc()->stats, stats);
 }
@@ -519,7 +523,7 @@ static bool mi_heap_buf_expand(mi_heap_buf_t* hbuf) {
     hbuf->buf[hbuf->size-1] = 0;
   }
   if (hbuf->size > SIZE_MAX/2 || !hbuf->can_realloc) return false;
-  const size_t newsize = (hbuf->size == 0 ? 2*MI_KiB : 2*hbuf->size);
+  const size_t newsize = (hbuf->size == 0 ? mi_good_size(12*MI_KiB) : 2*hbuf->size);
   char* const  newbuf  = (char*)mi_rezalloc(hbuf->buf, newsize);
   if (newbuf == NULL) return false;
   hbuf->buf = newbuf;
diff --git a/test/test-stress.c b/test/test-stress.c
index cd63b05e..ba6270ba 100644
--- a/test/test-stress.c
+++ b/test/test-stress.c
@@ -374,6 +374,7 @@ int main(int argc, char** argv) {
     mi_free(json);
   }
   #endif
+  mi_collect(true);
   mi_stats_print(NULL);  
 #endif
   //bench_end_program();