diff --git a/trunk/src/core/srs_core_performance.hpp b/trunk/src/core/srs_core_performance.hpp
index cbfddf1dc..6958aed4f 100644
--- a/trunk/src/core/srs_core_performance.hpp
+++ b/trunk/src/core/srs_core_performance.hpp
@@ -193,7 +193,15 @@
 #undef SRS_PERF_GLIBC_MEMORY_CHECK
 
 // For RTC, how many iovs we alloc for each mmsghdr for GSO.
-#define SRS_PERF_RTC_GSO_IOVS 4
+// Assume that there are 2400 clients, say, 60000 msgs in queue to send, the memory is:
+//      2                                       # We have two queue, cache and hotspot.
+//      * 4                                     # We have reuseport, each have msg cache queue.
+//      * (64 + SRS_PERF_RTC_GSO_IOVS * 1500)   # Each message size.
+//      * 60000                                 # Total messages.
+//      = 715MB                                 # For SRS_PERF_RTC_GSO_IOVS = 1
+//      = 1402MB                                # For SRS_PERF_RTC_GSO_IOVS = 2
+//      = 2775MB                                # For SRS_PERF_RTC_GSO_IOVS = 4
+#define SRS_PERF_RTC_GSO_IOVS 2
 
 #endif