Bringing this back to the list after some off-list tcpdumps... On 01/21/15 04:28, Mauro Ciancio wrote: > The problem I'm having is that spiped is adding latency (I guess so).
Turns out that this was caused by the interaction of nagling and TCP delayed ACK. I'm not sure why the Linux network stack wants to use these bandwidth-saving techniques when communicating over the loopback interface, but I'm sure someone had a very good reason. I've set TCP_NODELAY to disable nagling; the potential bandwidth waste due to TCP/IP overhead is minimal since spiped is sending 1060 bytes of TCP/IP payload at a time over the encrypted connection (1024 bytes of spiped payload + 4 byte payload length + 32 byte hmac). Commit: https://code.google.com/p/spiped/source/detail?r=184 I'll release spiped 1.5.0 at some point with this included. If anyone else has anything which they want to see in 1.5.0, make sure you speak up in the next few weeks. -- Colin Percival Security Officer Emeritus, FreeBSD | The power to serve Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid
