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--- libmalloc/libmalloc-646.0.13/src/magazine_medium.c
+++ libmalloc/libmalloc-374.100.5/src/magazine_medium.c
@@ -132,6 +132,25 @@
 	meta_headers[index] = 0;
 }
 
+static MALLOC_INLINE MALLOC_ALWAYS_INLINE
+mag_index_t
+medium_mag_get_thread_index(void)
+{
+#if CONFIG_MEDIUM_USES_HYPER_SHIFT
+	if (os_likely(_os_cpu_number_override == -1)) {
+		return _malloc_cpu_number() >> hyper_shift;
+	} else {
+		return _os_cpu_number_override >> hyper_shift;
+	}
+#else // CONFIG_MEDIUM_USES_HYPER_SHIFT
+	if (os_likely(_os_cpu_number_override == -1)) {
+		return _malloc_cpu_number();
+	} else {
+		return _os_cpu_number_override;
+	}
+#endif // CONFIG_MEDIUM_USES_HYPER_SHIFT
+}
+
 #pragma mark in-place free list
 
 static MALLOC_INLINE void
@@ -990,6 +1009,11 @@
 {
 	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);
@@ -1490,7 +1514,11 @@
 	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
@@ -2384,7 +2412,7 @@
 medium_malloc_should_clear(rack_t *rack, msize_t msize, boolean_t cleared_requested)
 {
 	void *ptr;
-	mag_index_t mag_index = rack_get_thread_index(rack) % rack->num_magazines;
+	mag_index_t mag_index = medium_mag_get_thread_index() % rack->num_magazines;
 	magazine_t *medium_mag_ptr = &(rack->magazines[mag_index]);
 
 	MALLOC_TRACE(TRACE_medium_malloc, (uintptr_t)rack, MEDIUM_BYTES_FOR_MSIZE(msize), (uintptr_t)medium_mag_ptr, cleared_requested);