diff --git a/include/jemalloc/internal/arena_stats.h b/include/jemalloc/internal/arena_stats.h
index 3d512630..7f075114 100644
--- a/include/jemalloc/internal/arena_stats.h
+++ b/include/jemalloc/internal/arena_stats.h
@@ -14,12 +14,18 @@ JEMALLOC_DIAGNOSTIC_DISABLE_SPURIOUS
 typedef struct arena_stats_large_s arena_stats_large_t;
 struct arena_stats_large_s {
 	/*
-	 * Total number of allocation/deallocation requests served directly by
-	 * the arena.
+	 * Total number of large allocation/deallocation requests served directly
+	 * by the arena.
 	 */
 	locked_u64_t	nmalloc;
 	locked_u64_t	ndalloc;
 
+	/*
+	 * Total large active bytes (allocated - deallocated) served directly
+	 * by the arena.
+	 */
+	locked_u64_t	active_bytes;
+
 	/*
 	 * Number of allocation requests that correspond to this size class.
 	 * This includes requests served by tcache, though tcache only
diff --git a/src/arena.c b/src/arena.c
index 884d1bf9..a66486b0 100644
--- a/src/arena.c
+++ b/src/arena.c
@@ -145,8 +145,18 @@ arena_stats_merge(tsdn_t *tsdn, arena_t *arena, unsigned *nthreads,
 		assert(nmalloc - ndalloc <= SIZE_T_MAX);
 		size_t curlextents = (size_t)(nmalloc - ndalloc);
 		lstats[i].curlextents += curlextents;
-		astats->allocated_large +=
-		    curlextents * sz_index2size(SC_NBINS + i);
+
+		if (config_limit_usize_gap) {
+			uint64_t active_bytes = locked_read_u64(tsdn,
+			    LOCKEDINT_MTX(arena->stats.mtx),
+			    &arena->stats.lstats[i].active_bytes);
+			locked_inc_u64_unsynchronized(
+			    &lstats[i].active_bytes, active_bytes);
+			astats->allocated_large += active_bytes;
+		} else {
+			astats->allocated_large +=
+			    curlextents * sz_index2size(SC_NBINS + i);
+		}
 	}
 
 	pa_shard_stats_merge(tsdn, &arena->pa_shard, &astats->pa_shard_stats,
@@ -315,6 +325,11 @@ arena_large_malloc_stats_update(tsdn_t *tsdn, arena_t *arena, size_t usize) {
 		LOCKEDINT_MTX_LOCK(tsdn, arena->stats.mtx);
 		locked_inc_u64(tsdn, LOCKEDINT_MTX(arena->stats.mtx),
 			&arena->stats.lstats[hindex].nmalloc, 1);
+		if (config_limit_usize_gap) {
+			locked_inc_u64(tsdn, LOCKEDINT_MTX(arena->stats.mtx),
+			    &arena->stats.lstats[hindex].active_bytes,
+			    usize);
+		}
 		LOCKEDINT_MTX_UNLOCK(tsdn, arena->stats.mtx);
 	}
 }
@@ -338,6 +353,11 @@ arena_large_dalloc_stats_update(tsdn_t *tsdn, arena_t *arena, size_t usize) {
 		LOCKEDINT_MTX_LOCK(tsdn, arena->stats.mtx);
 		locked_inc_u64(tsdn, LOCKEDINT_MTX(arena->stats.mtx),
 			&arena->stats.lstats[hindex].ndalloc, 1);
+		if (config_limit_usize_gap) {
+			locked_dec_u64(tsdn, LOCKEDINT_MTX(arena->stats.mtx),
+			    &arena->stats.lstats[hindex].active_bytes,
+			    usize);
+		}
 		LOCKEDINT_MTX_UNLOCK(tsdn, arena->stats.mtx);
 	}
 }
diff --git a/test/unit/stats.c b/test/unit/stats.c
index 203a71b5..584a582f 100644
--- a/test/unit/stats.c
+++ b/test/unit/stats.c
@@ -202,17 +202,22 @@ TEST_END
 
 TEST_BEGIN(test_stats_arenas_large) {
 	void *p;
-	size_t sz, allocated;
+	size_t sz, allocated, allocated_before;
 	uint64_t epoch, nmalloc, ndalloc;
+	size_t malloc_size = (1U << (SC_LG_LARGE_MINCLASS + 1)) + 1;
 	int expected = config_stats ? 0 : ENOENT;
 
-	p = mallocx((1U << SC_LG_LARGE_MINCLASS), MALLOCX_ARENA(0));
+	sz = sizeof(size_t);
+	expect_d_eq(mallctl("stats.arenas.0.large.allocated",
+	    (void *)&allocated_before, &sz, NULL, 0), expected,
+	    "Unexpected mallctl() result");
+
+	p = mallocx(malloc_size, MALLOCX_ARENA(0));
 	expect_ptr_not_null(p, "Unexpected mallocx() failure");
 
 	expect_d_eq(mallctl("epoch", NULL, NULL, (void *)&epoch, sizeof(epoch)),
 	    0, "Unexpected mallctl() failure");
 
-	sz = sizeof(size_t);
 	expect_d_eq(mallctl("stats.arenas.0.large.allocated",
 	    (void *)&allocated, &sz, NULL, 0), expected,
 	    "Unexpected mallctl() result");
@@ -223,8 +228,10 @@ TEST_BEGIN(test_stats_arenas_large) {
 	    &sz, NULL, 0), expected, "Unexpected mallctl() result");
 
 	if (config_stats) {
-		expect_zu_gt(allocated, 0,
+		expect_zu_ge(allocated_before, 0,
 		    "allocated should be greater than zero");
+		expect_zu_ge(allocated - allocated_before, sz_s2u(malloc_size),
+		    "the diff between allocated should be greater than the allocation made");
 		expect_u64_gt(nmalloc, 0,
 		    "nmalloc should be greater than zero");
 		expect_u64_ge(nmalloc, ndalloc,