diff --git a/include/mimalloc/internal.h b/include/mimalloc/internal.h
index 468963c8..6fce36cc 100644
--- a/include/mimalloc/internal.h
+++ b/include/mimalloc/internal.h
@@ -213,6 +213,7 @@ void          _mi_deferred_free(mi_heap_t* heap, bool force);
 void          _mi_page_free_collect(mi_page_t* page, bool force);
 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_bin_size(size_t bin);            // for stats
 size_t        _mi_bin(size_t size);                // for stats
diff --git a/include/mimalloc/types.h b/include/mimalloc/types.h
index 29d6fde9..a743546e 100644
--- a/include/mimalloc/types.h
+++ b/include/mimalloc/types.h
@@ -339,13 +339,13 @@ typedef struct mi_page_s {
 #endif
 
 // The max object size are checked to not waste more than 12.5% internally over the page sizes.
-#define MI_SMALL_MAX_OBJ_SIZE             ((MI_SMALL_PAGE_SIZE-MI_PAGE_INFO_SIZE)/8)   // < 8 KiB
+#define MI_SMALL_MAX_OBJ_SIZE             ((MI_SMALL_PAGE_SIZE-MI_PAGE_INFO_SIZE)/4)   // < 16 KiB
 #if MI_ENABLE_LARGE_PAGES
-#define MI_MEDIUM_MAX_OBJ_SIZE            ((MI_MEDIUM_PAGE_SIZE-MI_PAGE_INFO_SIZE)/8)  // < 64 KiB
+#define MI_MEDIUM_MAX_OBJ_SIZE            ((MI_MEDIUM_PAGE_SIZE-MI_PAGE_INFO_SIZE)/4)  // < 128 KiB
 #define MI_LARGE_MAX_OBJ_SIZE             (MI_LARGE_PAGE_SIZE/8)    // <= 512KiB // note: this must be a nice power of 2 or we get rounding issues with `_mi_bin`
 #else
-#define MI_MEDIUM_MAX_OBJ_SIZE            (MI_MEDIUM_PAGE_SIZE/8)   // <= 64 KiB
-#define MI_LARGE_MAX_OBJ_SIZE             MI_MEDIUM_MAX_OBJ_SIZE    // <= 64 KiB // note: this must be a nice power of 2 or we get rounding issues with `_mi_bin`
+#define MI_MEDIUM_MAX_OBJ_SIZE            (MI_MEDIUM_PAGE_SIZE/4)   // <= 128 KiB
+#define MI_LARGE_MAX_OBJ_SIZE             MI_MEDIUM_MAX_OBJ_SIZE    // note: this must be a nice power of 2 or we get rounding issues with `_mi_bin`
 #endif
 #define MI_LARGE_MAX_OBJ_WSIZE            (MI_LARGE_MAX_OBJ_SIZE/MI_SIZE_SIZE)
 
@@ -389,6 +389,7 @@ typedef struct mi_tld_s mi_tld_t;
 typedef struct mi_page_queue_s {
   mi_page_t* first;
   mi_page_t* last;
+  size_t     count;
   size_t     block_size;
 } mi_page_queue_t;
 
diff --git a/src/free.c b/src/free.c
index 1df10728..418acd02 100644
--- a/src/free.c
+++ b/src/free.c
@@ -202,6 +202,17 @@ void mi_free(void* p) mi_attr_noexcept
 // Multi-threaded Free (`_mt`)
 // ------------------------------------------------------
 static bool mi_page_unown_from_free(mi_page_t* page, mi_block_t* mt_free);
+static inline bool mi_page_queue_len_is_atmost( mi_heap_t* heap, size_t block_size, size_t atmost) {  
+  mi_page_queue_t* const pq = mi_page_queue(heap,block_size);
+  mi_assert_internal(pq!=NULL);
+  return (pq->count <= atmost);
+  /*
+  for(mi_page_t* p = pq->first; p!=NULL; p = p->next, atmost--) {
+    if (atmost == 0) { return false; }
+  }
+  return true;
+  */
+}
 
 static void mi_decl_noinline mi_free_try_collect_mt(mi_page_t* page, mi_block_t* mt_free) mi_attr_noexcept {
   mi_assert_internal(mi_page_is_owned(page));
@@ -243,7 +254,7 @@ static void mi_decl_noinline mi_free_try_collect_mt(mi_page_t* page, mi_block_t*
     }
     // can we reclaim?
     if (heap != NULL && heap->allow_page_reclaim) {
-      if (heap == page->heap ||                  // only reclaim if we were the originating heap,
+      if ((heap == page->heap && mi_page_queue_len_is_atmost(heap, page->block_size, 4)) ||  // only reclaim if we were the originating heap, and we have at most N pages already
           (reclaim_on_free == 1 &&               // OR if the reclaim across heaps is allowed
            !mi_page_is_used_at_frac(page, 8) &&  //    and the page is not too full
            !heap->tld->is_in_threadpool &&       //    and not part of a threadpool
diff --git a/src/heap.c b/src/heap.c
index d7fdaf6a..ac67698a 100644
--- a/src/heap.c
+++ b/src/heap.c
@@ -63,6 +63,9 @@ static bool mi_heap_page_is_valid(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_
 static bool mi_heap_is_valid(mi_heap_t* heap) {
   mi_assert_internal(heap!=NULL);
   mi_heap_visit_pages(heap, &mi_heap_page_is_valid, NULL, NULL);
+  for (size_t bin = 0; bin < MI_BIN_COUNT; bin++) {
+    mi_assert_internal(_mi_page_queue_is_valid(heap, &heap->pages[bin]));
+  }
   return true;
 }
 #endif
@@ -106,6 +109,7 @@ static bool mi_heap_page_collect(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_t
 static void mi_heap_collect_ex(mi_heap_t* heap, mi_collect_t collect)
 {
   if (heap==NULL || !mi_heap_is_initialized(heap)) return;
+  mi_assert_expensive(mi_heap_is_valid(heap));
 
   const bool force = (collect >= MI_FORCE);
   _mi_deferred_free(heap, force);
diff --git a/src/init.c b/src/init.c
index 5bedab85..4cac1c18 100644
--- a/src/init.c
+++ b/src/init.c
@@ -50,7 +50,7 @@ const mi_page_t _mi_page_empty = {
 
 
 // Empty page queues for every bin
-#define QNULL(sz)  { NULL, NULL, (sz)*sizeof(uintptr_t) }
+#define QNULL(sz)  { NULL, NULL, 0, (sz)*sizeof(uintptr_t) }
 #define MI_PAGE_QUEUES_EMPTY \
   { QNULL(1), \
     QNULL(     1), QNULL(     2), QNULL(     3), QNULL(     4), QNULL(     5), QNULL(     6), QNULL(     7), QNULL(     8), /* 8 */ \
diff --git a/src/page-queue.c b/src/page-queue.c
index 75189e1a..6e8b0853 100644
--- a/src/page-queue.c
+++ b/src/page-queue.c
@@ -49,6 +49,10 @@ static inline bool mi_page_queue_is_special(const mi_page_queue_t* pq) {
   return (pq->block_size > MI_LARGE_MAX_OBJ_SIZE);
 }
 
+static inline size_t mi_page_queue_count(const mi_page_queue_t* pq) {
+  return pq->count;
+}
+
 /* -----------------------------------------------------------
   Bins
 ----------------------------------------------------------- */
@@ -136,6 +140,34 @@ static bool mi_heap_contains_queue(const mi_heap_t* heap, const mi_page_queue_t*
 }
 #endif
 
+bool _mi_page_queue_is_valid(mi_heap_t* heap, const mi_page_queue_t* pq) {
+  MI_UNUSED_RELEASE(heap);
+  if (pq==NULL) return false;
+  size_t count = 0; MI_UNUSED_RELEASE(count);
+  mi_page_t* prev = NULL; MI_UNUSED_RELEASE(prev);
+  for (mi_page_t* page = pq->first; page != NULL; page = page->next) {
+    mi_assert_internal(page->prev == prev);
+    if (mi_page_is_in_full(page)) {
+      mi_assert_internal(_mi_wsize_from_size(pq->block_size) == MI_LARGE_MAX_OBJ_WSIZE + 2); 
+    }
+    else if (mi_page_is_huge(page)) {
+      mi_assert_internal(_mi_wsize_from_size(pq->block_size) == MI_LARGE_MAX_OBJ_WSIZE + 1); 
+    }
+    else {
+      mi_assert_internal(mi_page_block_size(page) == pq->block_size);
+    }
+    mi_assert_internal(page->heap == heap);
+    if (page->next == NULL) {
+      mi_assert_internal(pq->last == page);
+    }
+    count++;
+    prev = page;
+  }
+  mi_assert_internal(pq->count == count);
+  return true;
+}
+
+
 static mi_page_queue_t* mi_heap_page_queue_of(mi_heap_t* heap, const mi_page_t* page) {
   mi_assert_internal(heap!=NULL);
   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))));
@@ -205,6 +237,7 @@ static bool mi_page_queue_is_empty(mi_page_queue_t* queue) {
 static void mi_page_queue_remove(mi_page_queue_t* queue, mi_page_t* page) {
   mi_assert_internal(page != NULL);
   mi_assert_expensive(mi_page_queue_contains(queue, page));
+  mi_assert_internal(queue->count >= 1);
   mi_assert_internal(mi_page_block_size(page) == queue->block_size ||
                       (mi_page_is_huge(page) && mi_page_queue_is_huge(queue)) ||
                         (mi_page_is_in_full(page) && mi_page_queue_is_full(queue)));
@@ -219,6 +252,7 @@ static void mi_page_queue_remove(mi_page_queue_t* queue, mi_page_t* page) {
     mi_heap_queue_first_update(heap,queue);
   }
   heap->page_count--;
+  queue->count--;
   page->next = NULL;
   page->prev = NULL;
   mi_page_set_in_full(page,false);
@@ -247,6 +281,7 @@ static void mi_page_queue_push(mi_heap_t* heap, mi_page_queue_t* queue, mi_page_
   else {
     queue->first = queue->last = page;
   }
+  queue->count++;
 
   // update direct
   mi_heap_queue_first_update(heap, queue);
@@ -273,6 +308,7 @@ static void mi_page_queue_push_at_end(mi_heap_t* heap, mi_page_queue_t* queue, m
   else {
     queue->first = queue->last = page;
   }
+  queue->count++;
 
   // update direct
   if (queue->first == page) {
@@ -292,6 +328,7 @@ static void mi_page_queue_move_to_front(mi_heap_t* heap, mi_page_queue_t* queue,
 
 static void mi_page_queue_enqueue_from_ex(mi_page_queue_t* to, mi_page_queue_t* from, bool enqueue_at_end, mi_page_t* page) {
   mi_assert_internal(page != NULL);
+  mi_assert_internal(from->count >= 1);
   mi_assert_expensive(mi_page_queue_contains(from, page));
   mi_assert_expensive(!mi_page_queue_contains(to, page));
   const size_t bsize = mi_page_block_size(page);
@@ -314,8 +351,10 @@ static void mi_page_queue_enqueue_from_ex(mi_page_queue_t* to, mi_page_queue_t*
     mi_assert_internal(mi_heap_contains_queue(heap, from));
     mi_heap_queue_first_update(heap, from);
   }
+  from->count--;
 
   // insert into `to`
+  to->count++;
   if (enqueue_at_end) {
     // enqueue at the end
     page->prev = to->last;
@@ -372,15 +411,16 @@ static void mi_page_queue_enqueue_from_full(mi_page_queue_t* to, mi_page_queue_t
 size_t _mi_page_queue_append(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_queue_t* append) {
   mi_assert_internal(mi_heap_contains_queue(heap,pq));
   mi_assert_internal(pq->block_size == append->block_size);
-
+  
   if (append->first==NULL) return 0;
-
+  
   // set append pages to new heap and count
   size_t count = 0;
   for (mi_page_t* page = append->first; page != NULL; page = page->next) {
     mi_page_set_heap(page, heap);
     count++;
   }
+  mi_assert_internal(count == append->count);
 
   if (pq->last==NULL) {
     // take over afresh
@@ -397,5 +437,7 @@ size_t _mi_page_queue_append(mi_heap_t* heap, mi_page_queue_t* pq, mi_page_queue
     append->first->prev = pq->last;
     pq->last = append->last;
   }
+  pq->count += append->count;
+
   return count;
 }