-#define MAX_BLOCKTIME 59.731
-#define PID_HASHSIZE 16 /* size of pid hahs table, must be power of two */
+#define MAX_BLOCKTIME 59.731 /* never wait longer than this time (to detetc time jumps) */
+#define PID_HASHSIZE 16 /* size of pid hash table, must be power of two */
+#define CLEANUP_INTERVAL (MAX_BLOCKTIME * 5.) /* how often to try to free memory and re-check fds */