--- libmalloc/libmalloc-409.40.6/src/magazine_medium.c
+++ libmalloc/libmalloc-317.140.5/src/magazine_medium.c
@@ -32,29 +32,15 @@
 static MALLOC_INLINE uint64_t
 medium_sliding_madvise_granularity(magazine_t *magazine)
 {
-	uint64_t granularity = MEDIUM_MADVISE_MIN;
 	// Use a sliding madvise granularity based on how many bytes the region
 	// currently has allocated. This way we will advise at a finer granularity
 	// as the region becomes more and more empty.
 	// region_trailer_t *t = REGION_TRAILER_FOR_MEDIUM_REGION(region);
-	if (magazine->mag_num_bytes_in_objects > 0) {
-		if (magazine_medium_madvise_window_scale_factor == 1) {
-			// NB: This code has a bug causing undefined behavior whenever the result of clzl is > 32
-			// because it's shifting a signed integer. It should be 1ULL << (64 - ...) but
-			// fixing this bug will introduce memory regressions, so for now we've only fixed it on very
-			// large memory configs that are scaling up their window anyways.
-			// See rdar://82128925 for details
-			granularity = MAX(granularity, 1 << (64 -
-					__builtin_clzl(magazine->mag_num_bytes_in_objects >> MEDIUM_MADVISE_SHIFT)));
-		} else {
-			granularity = MAX(granularity, 1ULL << (64 -
-					__builtin_clzl(magazine->mag_num_bytes_in_objects >> MEDIUM_MADVISE_SHIFT)));
-			if (os_mul_overflow(granularity, magazine_medium_madvise_window_scale_factor, &granularity)) {
-				return UINT64_MAX;
-			}
-		}
-	}
-	return granularity;
+	if (magazine->mag_num_bytes_in_objects == 0) {
+		return MEDIUM_MADVISE_MIN;
+	}
+	return MAX(MEDIUM_MADVISE_MIN, 1 << (64 -
+			__builtin_clzl(magazine->mag_num_bytes_in_objects >> MEDIUM_MADVISE_SHIFT)));
 }
 
 static MALLOC_INLINE void
@@ -1009,6 +995,11 @@
 {
 	magazine_t *depot_ptr = &(rack->magazines[DEPOT_MAGAZINE_INDEX]);
 
+	/* FIXME: Would Uniprocessor benefit from recirc and MADV_FREE? */
+	if (rack->num_magazines == 1) { // Uniprocessor, single magazine, so no recirculation necessary
+		return 0;
+	}
+
 #if DEBUG_MALLOC
 	if (DEPOT_MAGAZINE_INDEX == mag_index) {
 		malloc_zone_error(rack->debug_flags, true, "medium_get_region_from_depot called for magazine index -1\n", NULL, NULL);
@@ -1021,32 +1012,22 @@
 	// Appropriate a Depot'd region that can satisfy requested msize.
 	region_trailer_t *node;
 	region_t sparse_region;
-	msize_t try_msize = msize;
 
 	while (1) {
-		sparse_region = medium_find_msize_region(rack, depot_ptr, DEPOT_MAGAZINE_INDEX, try_msize);
+		sparse_region = medium_find_msize_region(rack, depot_ptr, DEPOT_MAGAZINE_INDEX, msize);
 		if (NULL == sparse_region) { // Depot empty?
 			SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
 			return 0;
 		}
 
 		node = REGION_TRAILER_FOR_MEDIUM_REGION(sparse_region);
-		if (0 == node->pinned_to_depot) {
-			// Found one!
+		if (0 >= node->pinned_to_depot) {
 			break;
 		}
 
-		// Try the next msize up - maybe the head of its free list will be in
-		// a region we can use. Once we get the region we'll still allocate the
-		// original msize.
-		try_msize++;
-
-		if (try_msize > NUM_MEDIUM_SLOTS) {
-			// Tried all the msizes but couldn't get a usable region. Let's
-			// give up for now and we'll allocate a new region from the kernel.
-			SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
-			return 0;
-		}
+		SZONE_MAGAZINE_PTR_UNLOCK(depot_ptr);
+		yield();
+		SZONE_MAGAZINE_PTR_LOCK(depot_ptr);
 	}
 
 	// disconnect node from Depot
@@ -1057,7 +1038,7 @@
 
 	// Transfer ownership of the region
 	MAGAZINE_INDEX_FOR_MEDIUM_REGION(sparse_region) = mag_index;
-	MALLOC_ASSERT(node->pinned_to_depot == 0);
+	node->pinned_to_depot = 0;
 
 	// Iterate the region putting its free entries on its new (locked) magazine's free list
 	size_t bytes_inplay = medium_free_reattach_region(rack, medium_mag_ptr, sparse_region);
@@ -1148,7 +1129,7 @@
 
 			SZONE_MAGAZINE_PTR_LOCK(medium_depot_ptr);
 			MAGAZINE_INDEX_FOR_MEDIUM_REGION(medium) = DEPOT_MAGAZINE_INDEX;
-			MALLOC_ASSERT(REGION_TRAILER_FOR_MEDIUM_REGION(medium)->pinned_to_depot == 0);
+			REGION_TRAILER_FOR_MEDIUM_REGION(medium)->pinned_to_depot = 0;
 
 			size_t bytes_inplay = medium_free_reattach_region(rack, medium_depot_ptr, medium);
 
@@ -1260,17 +1241,7 @@
 	// If the target region is madvisable, then madvise whatever we can but
 	// bound it by the safe_start/end pointers to make sure we don't clobber
 	// the free-list.
-	bool should_madvise = (vote_force == 2) || (dirty_msz >= trigger_msize);
-	if (magazine_medium_madvise_window_scale_factor > 1) {
-		// trigger_msize is an unsigned short, but it's possible that trigger level was larger than UINT16_MAX
-		// even after we shifted it. In this case the window rolls around to 0. This is even more likely
-		// if we're scaling the window up. We should fix the truncation bug above, but doing so
-		// will cause a memory regression. For now, we avoid using trigger_msize iff we're scaling
-		// the window up since truncating to 0 would be self-defeating in this case.
-		// See rdar://82128639 for details
-		should_madvise = (vote_force == 2) || (MEDIUM_BYTES_FOR_MSIZE(dirty_msz) >= trigger_level);
-	}
-	if (should_madvise) {
+	if ((vote_force == 2) || (dirty_msz >= trigger_msize)) {
 		uintptr_t lo = MAX((uintptr_t)MEDIUM_PTR_FOR_META_INDEX(region, range_idx),
 				safe_start_ptr);
 		uintptr_t hi = MIN((uintptr_t)MEDIUM_PTR_FOR_META_INDEX(region, range_idx) +
@@ -1509,7 +1480,11 @@
 	region_trailer_t *node = REGION_TRAILER_FOR_MEDIUM_REGION(region);
 	size_t bytes_used = node->bytes_used;
 
-	if (DEPOT_MAGAZINE_INDEX != mag_index) {
+	/* FIXME: Would Uniprocessor benefit from recirc and MADV_FREE? */
+	if (rack->num_magazines == 1) { // Uniprocessor, single magazine, so no recirculation necessary
+		/* NOTHING */
+		return TRUE; // Caller must do SZONE_MAGAZINE_PTR_UNLOCK(tiny_mag_ptr)
+	} else if (DEPOT_MAGAZINE_INDEX != mag_index) {
 		// Emptiness discriminant
 		if (bytes_used < DENSITY_THRESHOLD(MEDIUM_REGION_PAYLOAD_BYTES)) {
 			/* Region has crossed threshold from density to sparsity. Mark it "suitable" on the
@@ -1895,8 +1870,7 @@
 			// use is adjusted by the medium_meta_header_set_middle() call below.
 			medium_meta_header_set_in_use(meta_headers, index + new_msize, leftover_msize);
 
-			/* Propagate the madvise information from the block we're using to the leftover block. */
-			if (madv_headers[next_index] & MEDIUM_IS_ADVISED) {
+			if (madv_headers[index] & MEDIUM_IS_ADVISED) {
 				medium_madvise_header_mark_clean(madv_headers, index + new_msize, leftover_msize);
 			} else {
 				medium_madvise_header_mark_dirty(madv_headers, index + new_msize, leftover_msize);
@@ -2297,7 +2271,7 @@
 	if ((ptr = medium_free_list_get_ptr(rack, *free_list))) {
 		this_msize = MEDIUM_PTR_SIZE(ptr);
 		was_madvised = (medium_madvise_header_dirty_len(
-				MEDIUM_MADVISE_HEADER_FOR_PTR(ptr), MEDIUM_META_INDEX_FOR_PTR(ptr)) == 0);
+				MEDIUM_MADVISE_HEADER_FOR_PTR(ptr), this_msize) == 0);
 		medium_free_list_remove_ptr(rack, medium_mag_ptr, *free_list, this_msize);
 		goto add_leftover_and_proceed;
 	}