diff --git a/include/jemalloc/internal/tcache_externs.h b/include/jemalloc/internal/tcache_externs.h
index e043ef49..1924fd9c 100644
--- a/include/jemalloc/internal/tcache_externs.h
+++ b/include/jemalloc/internal/tcache_externs.h
@@ -8,6 +8,7 @@ extern unsigned opt_tcache_nslots_small_min;
 extern unsigned opt_tcache_nslots_small_max;
 extern unsigned opt_tcache_nslots_large;
 extern ssize_t opt_lg_tcache_shift;
+extern size_t opt_tcache_gc_incr_bytes;
 
 /*
  * Number of tcache bins.  There are SC_NBINS small-object bins, plus 0 or more
diff --git a/include/jemalloc/internal/tcache_types.h b/include/jemalloc/internal/tcache_types.h
index c8fd4c3e..fb311e72 100644
--- a/include/jemalloc/internal/tcache_types.h
+++ b/include/jemalloc/internal/tcache_types.h
@@ -17,9 +17,6 @@ typedef struct tcaches_s tcaches_t;
 #define TCACHE_STATE_PURGATORY		((tcache_t *)(uintptr_t)3)
 #define TCACHE_STATE_MAX		TCACHE_STATE_PURGATORY
 
-/* Number of allocation bytes between tcache incremental GCs. */
-#define TCACHE_GC_INCR_BYTES 65536U
-
 /* Used in TSD static initializer only. Real init in tsd_tcache_data_init(). */
 #define TCACHE_ZERO_INITIALIZER {0}
 #define TCACHE_SLOW_ZERO_INITIALIZER {0}
diff --git a/include/jemalloc/internal/thread_event.h b/include/jemalloc/internal/thread_event.h
index 5b5bb9fb..2fcaa88a 100644
--- a/include/jemalloc/internal/thread_event.h
+++ b/include/jemalloc/internal/thread_event.h
@@ -53,10 +53,10 @@ void tsd_te_init(tsd_t *tsd);
  *  E(event,		(condition), is_alloc_event)
  */
 #define ITERATE_OVER_ALL_EVENTS						\
-    E(tcache_gc,	(TCACHE_GC_INCR_BYTES > 0), true)		\
+    E(tcache_gc,	(opt_tcache_gc_incr_bytes > 0), true)		\
     E(prof_sample,	(config_prof && opt_prof), true)	    	\
     E(stats_interval,	(opt_stats_interval >= 0), true)	    	\
-    E(tcache_gc_dalloc,	(TCACHE_GC_INCR_BYTES > 0), false)
+    E(tcache_gc_dalloc,	(opt_tcache_gc_incr_bytes > 0), false)
 
 #define E(event, condition_unused, is_alloc_event_unused)		\
     C(event##_event_wait)
diff --git a/src/jemalloc.c b/src/jemalloc.c
index 4f911e22..068a840a 100644
--- a/src/jemalloc.c
+++ b/src/jemalloc.c
@@ -1389,6 +1389,10 @@ malloc_conf_init_helper(sc_data_t *sc_data, unsigned bin_shard_sizes[SC_NBINS],
 			CONF_HANDLE_UNSIGNED(opt_tcache_nslots_large,
 			    "tcache_nslots_large", 1, 2048,
 			    CONF_CHECK_MIN, CONF_CHECK_MAX, /* clip */ true)
+			CONF_HANDLE_SIZE_T(opt_tcache_gc_incr_bytes,
+			    "tcache_gc_incr_bytes", 1024, SIZE_T_MAX,
+			    CONF_CHECK_MIN, CONF_DONT_CHECK_MAX,
+			    /* clip */ true)
 
 			/*
 			 * The runtime option of oversize_threshold remains
diff --git a/src/tcache.c b/src/tcache.c
index 0366149d..9b4a7b7a 100644
--- a/src/tcache.c
+++ b/src/tcache.c
@@ -33,6 +33,12 @@ unsigned opt_tcache_nslots_large = 20;
  */
 ssize_t	opt_lg_tcache_nslots_mul = -1;
 
+/*
+ * Number of allocation bytes between tcache incremental GCs.  Again, this
+ * default just seems to work well; more tuning is possible.
+ */
+size_t opt_tcache_gc_incr_bytes = 65536;
+
 cache_bin_info_t	*tcache_bin_info;
 
 /* Total stack size required (per tcache).  Include the padding above. */
@@ -62,7 +68,7 @@ tcache_salloc(tsdn_t *tsdn, const void *ptr) {
 
 uint64_t
 tcache_gc_new_event_wait(tsd_t *tsd) {
-	return TCACHE_GC_INCR_BYTES;
+	return opt_tcache_gc_incr_bytes;
 }
 
 uint64_t
@@ -72,7 +78,7 @@ tcache_gc_postponed_event_wait(tsd_t *tsd) {
 
 uint64_t
 tcache_gc_dalloc_new_event_wait(tsd_t *tsd) {
-	return TCACHE_GC_INCR_BYTES;
+	return opt_tcache_gc_incr_bytes;
 }
 
 uint64_t
diff --git a/test/stress/fill_flush.c b/test/stress/fill_flush.c
index 6ea3ff96..a2db044d 100644
--- a/test/stress/fill_flush.c
+++ b/test/stress/fill_flush.c
@@ -69,7 +69,6 @@ TEST_BEGIN(test_array_vs_item_large) {
 }
 TEST_END
 
-
 int main(void) {
 	return test_no_reentrancy(
 	    test_array_vs_item_small,