[pisa-src] r1008 - trunk/include

Author: tjansen
Date: Wed Sep 30 17:12:09 2009
New Revision: 1008

Log:
MTU tweaking part 2. Even bigger buffers for testing.

Modified:
   trunk/include/global.h

Modified: trunk/include/global.h
==============================================================================
--- trunk/include/global.h      Wed Sep 30 16:59:05 2009        (r1007)
+++ trunk/include/global.h      Wed Sep 30 17:12:09 2009        (r1008)
@@ -34,16 +34,20 @@
 
 /**
  * Size of the MTU for our tunnel device
- * The MTU of 1000 was found out by trial and error - 1050 didn't work for me
- * - neither via hipd nor via std-ipv6 connection (PMTU in both cases was
- *   1500)
+ * 1370 (MTU of dummy0) - 20 (IPv4) - 8 (UDP) - 6 (MAC) = 1336 (payload).
+ *
+ * Since the kernel fragments PISA packets that are too large for the dummy0
+ * interface, we could actually trade off processing of PISA packets against
+ * fragmentation. For further experiments, you can use
+ * "ifconfig pisaTunnel0 mtu $MTU" on the command line after pisa{c,s}d is
+ * started.
  */
 #define MTU_TUN 1336
 
 /**
  * Size of the buffers used to receive packets.
  */
-#define MAX_PACKET_BUFFER_TUN  MTU_TUN + 500
+#define MAX_PACKET_BUFFER_TUN  MTU_TUN + 1500
 
 /**
  * Maximum value for a normal packet buffer

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