diff --git a/lib/core/context.c b/lib/core/context.c
index d11246ef1..f52d7e7d8 100644
--- a/lib/core/context.c
+++ b/lib/core/context.c
@@ -394,6 +394,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 #if defined(LWS_WITH_NETWORK)
 	unsigned short count_threads = 1;
 	uint8_t *u;
+	uint16_t us_wait_resolution = 0;
 #endif
 #if defined(__ANDROID__)
 	struct rlimit rt;
@@ -469,6 +470,13 @@ lws_create_context(const struct lws_context_creation_info *info)
 	{
 		extern const lws_plugin_evlib_t evlib_poll;
 		plev = &evlib_poll;
+#if !defined(LWS_PLAT_FREERTOS)
+		/*
+		 * ... freertos has us-resolution select()...
+		 * others are to ms-resolution poll()
+		 */
+		us_wait_resolution = 1000;
+#endif
 	}
 #endif
 
@@ -575,6 +583,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 		extern const lws_plugin_evlib_t evlib_uv;
 		plev = &evlib_uv;
 		fatal_exit_defer = !!info->foreign_loops;
+		us_wait_resolution = 0;
 	}
 #endif
 
@@ -582,6 +591,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 	if (lws_check_opt(info->options, LWS_SERVER_OPTION_LIBEVENT)) {
 		extern const lws_plugin_evlib_t evlib_event;
 		plev = &evlib_event;
+		us_wait_resolution = 0;
 	}
 #endif
 
@@ -589,6 +599,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 	if (lws_check_opt(info->options, LWS_SERVER_OPTION_GLIB)) {
 		extern const lws_plugin_evlib_t evlib_glib;
 		plev = &evlib_glib;
+		us_wait_resolution = 0;
 	}
 #endif
 
@@ -596,6 +607,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 	if (lws_check_opt(info->options, LWS_SERVER_OPTION_LIBEV)) {
 		extern const lws_plugin_evlib_t evlib_ev;
 		plev = &evlib_ev;
+		us_wait_resolution = 0;
 	}
 #endif
 
@@ -603,6 +615,7 @@ lws_create_context(const struct lws_context_creation_info *info)
     if (lws_check_opt(info->options, LWS_SERVER_OPTION_SDEVENT)) {
         extern const lws_plugin_evlib_t evlib_sd;
         plev = &evlib_sd;
+        us_wait_resolution = 0;
     }
 #endif
 
@@ -628,6 +641,7 @@ lws_create_context(const struct lws_context_creation_info *info)
 
 #if defined(LWS_WITH_NETWORK)
 	context->event_loop_ops = plev->ops;
+	context->us_wait_resolution = us_wait_resolution;
 #endif
 #if defined(LWS_WITH_EVENT_LIBS)
 	/* at the very end */
diff --git a/lib/core/private-lib-core.h b/lib/core/private-lib-core.h
index e713b064e..c2f5a3576 100644
--- a/lib/core/private-lib-core.h
+++ b/lib/core/private-lib-core.h
@@ -640,6 +640,8 @@ struct lws_context {
 #if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
 	uint16_t	ss_proxy_port;
 #endif
+	/* 0 if not known, else us resolution of the poll wait */
+	uint16_t us_wait_resolution;
 
 	uint8_t max_fi;
 	uint8_t udp_loss_sim_tx_pc;
diff --git a/lib/event-libs/private-lib-event-libs.h b/lib/event-libs/private-lib-event-libs.h
index 35bfcd885..3c249498e 100644
--- a/lib/event-libs/private-lib-event-libs.h
+++ b/lib/event-libs/private-lib-event-libs.h
@@ -1,7 +1,7 @@
  /*
  * libwebsockets - small server side websockets and web server implementation
  *
- * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
+ * Copyright (C) 2010 - 2021 Andy Green <andy@warmcat.com>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to
diff --git a/lib/plat/unix/unix-service.c b/lib/plat/unix/unix-service.c
index 8428bf86c..e076a8871 100644
--- a/lib/plat/unix/unix-service.c
+++ b/lib/plat/unix/unix-service.c
@@ -115,7 +115,13 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 	 */
 	us = __lws_sul_service_ripe(pt->pt_sul_owner, LWS_COUNT_PT_SUL_OWNERS, us);
 	if (us && us < timeout_us)
-		timeout_us = us;
+		/*
+		 * If something wants zero wait, that's OK, but if the next sul
+		 * coming ripe is an interval less than our wait resolution,
+		 * bump it to be the wait resolution.
+		 */
+		timeout_us = us < context->us_wait_resolution ?
+					context->us_wait_resolution : us;
 
 	lws_pt_unlock(pt);
 
diff --git a/lib/plat/windows/windows-service.c b/lib/plat/windows/windows-service.c
index 4cc94e5b7..a64501d36 100644
--- a/lib/plat/windows/windows-service.c
+++ b/lib/plat/windows/windows-service.c
@@ -1,7 +1,7 @@
 /*
  * libwebsockets - small server side websockets and web server implementation
  *
- * Copyright (C) 2010 - 2019 Andy Green <andy@warmcat.com>
+ * Copyright (C) 2010 - 2021 Andy Green <andy@warmcat.com>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to
@@ -133,7 +133,13 @@ _lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 					    LWS_COUNT_PT_SUL_OWNERS,
 					    lws_now_usecs());
 		if (us && us < timeout_us)
-			timeout_us = us;
+			/*
+			 * If something wants zero wait, that's OK, but if the next sul
+			 * coming ripe is an interval less than our wait resolution,
+			 * bump it to be the wait resolution.
+			 */
+			timeout_us = us < context->us_wait_resolution ?
+					context->us_wait_resolution : us;
 
 		lws_pt_unlock(pt);
 	}