diff --git a/sslh-select.c b/sslh-select.c
index 6de23f9..1bf0dec 100644
--- a/sslh-select.c
+++ b/sslh-select.c
@@ -20,6 +20,14 @@
 
 */
 
+/* Why use select(2) rather than poll(2)?
+ * No real reason except that's how it was written at first. This article:
+ * https://daniel.haxx.se/docs/poll-vs-select.html suggests that over a few
+ * hundred file descriptors, both become very slow, so there is little
+ * incentive to move to poll() to support more than FD_SETSIZE (which is 1024
+ * on many Linux. To support large numbers of descriptors, either use the fork
+ * version, or we'll have to write a new version based on libev. */
+
 #define __LINUX__
 
 #include "common.h"