diff --git a/include/mimalloc/types.h b/include/mimalloc/types.h
index daf44a22..2f76cfe6 100644
--- a/include/mimalloc/types.h
+++ b/include/mimalloc/types.h
@@ -343,10 +343,10 @@ typedef struct mi_page_s {
 // 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
 #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)/8)  // < ~64 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/4)   // <= 128 KiB
+#define MI_MEDIUM_MAX_OBJ_SIZE            (MI_MEDIUM_PAGE_SIZE/8)   // <= 64 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)
diff --git a/src/bitmap.c b/src/bitmap.c
index 2d0bb8f3..908562c0 100644
--- a/src/bitmap.c
+++ b/src/bitmap.c
@@ -1560,7 +1560,7 @@ static inline bool mi_bbitmap_try_find_and_clear_generic(mi_bbitmap_t* bbitmap,
       const mi_bfield_t cmap_entry = mi_atomic_load_relaxed(&bbitmap->chunkmap.bfields[cmap_idx]);
       const size_t cmap_entry_cycle = (cmap_idx != cmap_acc ? MI_BFIELD_BITS : cmap_acc_bits);
       size_t eidx = 0;
-      mi_bfield_cycle_iterate(cmap_entry, tseq%8, cmap_entry_cycle, eidx, Y) 
+      mi_bfield_cycle_iterate(cmap_entry, tseq, cmap_entry_cycle, eidx, Y) 
       {
         mi_assert_internal(eidx <= MI_BFIELD_BITS);
         
diff --git a/src/options.c b/src/options.c
index bf6cf437..94cb8b67 100644
--- a/src/options.c
+++ b/src/options.c
@@ -175,7 +175,7 @@ static mi_option_desc_t options[_mi_option_last] =
   { 0,   UNINIT, MI_OPTION(max_vabits) },               // max virtual address space bits
   { MI_DEFAULT_PAGEMAP_COMMIT,
          UNINIT, MI_OPTION(pagemap_commit) },           // commit the full pagemap upfront?
-  { 0,   UNINIT, MI_OPTION(page_commit_on_demand) },    // commit pages on-demand (2 disables this only on overcommit systems (like Linux))
+  { 1,   UNINIT, MI_OPTION(page_commit_on_demand) },    // commit pages on-demand (2 disables this only on overcommit systems (like Linux))
   { 16,  UNINIT, MI_OPTION(page_reclaim_max) },         // don't reclaim pages if we already own N pages (in that size class)
 };