HPA: Add min_purge_interval_ms option

This rate limiting option is required to avoid purging too often.

include/jemalloc/internal/hpa_opts.h

@@ -43,6 +43,11 @@ struct hpa_shard_opts_s {
 	 * actually get hugified.
 	 */
 	uint64_t hugify_delay_ms;
+
+	/*
+	 * Minimum amount of time between purges.
+	 */
+	uint64_t min_purge_interval_ms;
 };
 
 #define HPA_SHARD_OPTS_DEFAULT {					\
@@ -61,7 +66,9 @@ struct hpa_shard_opts_s {
 	 */								\
 	false,								\
 	/* hugify_delay_ms */						\
-	10 * 1000							\
+	10 * 1000,							\
+	/* min_purge_interval_ms */					\
+	5 * 1000							\
 }
 
 #endif /* JEMALLOC_INTERNAL_HPA_OPTS_H */

src/ctl.c

@@ -97,6 +97,7 @@ CTL_PROTO(opt_hpa)
 CTL_PROTO(opt_hpa_slab_max_alloc)
 CTL_PROTO(opt_hpa_hugification_threshold)
 CTL_PROTO(opt_hpa_hugify_delay_ms)
+CTL_PROTO(opt_hpa_min_purge_interval_ms)
 CTL_PROTO(opt_hpa_dirty_mult)
 CTL_PROTO(opt_hpa_sec_nshards)
 CTL_PROTO(opt_hpa_sec_max_alloc)
@@ -408,6 +409,7 @@ static const ctl_named_node_t opt_node[] = {
 	{NAME("hpa_hugification_threshold"),
 		CTL(opt_hpa_hugification_threshold)},
 	{NAME("hpa_hugify_delay_ms"), CTL(opt_hpa_hugify_delay_ms)},
+	{NAME("hpa_min_purge_interval_ms"), CTL(opt_hpa_min_purge_interval_ms)},
 	{NAME("hpa_dirty_mult"), CTL(opt_hpa_dirty_mult)},
 	{NAME("hpa_sec_nshards"),	CTL(opt_hpa_sec_nshards)},
 	{NAME("hpa_sec_max_alloc"),	CTL(opt_hpa_sec_max_alloc)},
@@ -2116,6 +2118,8 @@ CTL_RO_NL_GEN(opt_hpa, opt_hpa, bool)
 CTL_RO_NL_GEN(opt_hpa_hugification_threshold,
     opt_hpa_opts.hugification_threshold, size_t)
 CTL_RO_NL_GEN(opt_hpa_hugify_delay_ms, opt_hpa_opts.hugify_delay_ms, uint64_t)
+CTL_RO_NL_GEN(opt_hpa_min_purge_interval_ms, opt_hpa_opts.min_purge_interval_ms,
+    uint64_t)
 
 /*
  * This will have to change before we publicly document this option; fxp_t and

src/jemalloc.c

@@ -1447,9 +1447,15 @@ malloc_conf_init_helper(sc_data_t *sc_data, unsigned bin_shard_sizes[SC_NBINS],
 				CONF_CONTINUE;
 			}
 
-			CONF_HANDLE_SIZE_T(
+			CONF_HANDLE_UINT64_T(
 			    opt_hpa_opts.hugify_delay_ms, "hpa_hugify_delay_ms",
-			    0, 0, CONF_CHECK_MIN, CONF_DONT_CHECK_MAX, true);
+			    0, 0, CONF_DONT_CHECK_MIN, CONF_DONT_CHECK_MAX,
+			    false);
+
+			CONF_HANDLE_UINT64_T(
+			    opt_hpa_opts.min_purge_interval_ms,
+			    "hpa_min_purge_interval_ms", 0, 0,
+			    CONF_DONT_CHECK_MIN, CONF_DONT_CHECK_MAX, false);
 
 			if (CONF_MATCH("hpa_dirty_mult")) {
 				if (CONF_MATCH_VALUE("-1")) {

src/stats.c

@@ -1472,6 +1472,7 @@ stats_general_print(emitter_t *emitter) {
 	OPT_WRITE_SIZE_T("hpa_slab_max_alloc")
 	OPT_WRITE_SIZE_T("hpa_hugification_threshold")
 	OPT_WRITE_UINT64("hpa_hugify_delay_ms")
+	OPT_WRITE_UINT64("hpa_min_purge_interval_ms")
 	if (je_mallctl("opt.hpa_dirty_mult", (void *)&u32v, &u32sz, NULL, 0)
 	    == 0) {
 		/*