[Spread-users] Spread Performance Questions

[Daniel Marques]

Hi All,

I'm running some quickie experiments with Spread and was wondering if
anyone could help explain some performance results I'm seeing.

Spread is configured as follows:

Spread_Segment  192.168.143.255:4803 {
	a 192.168.143.86
	b 192.168.143.56
}

There are two Spread processes running, the 'server' on machine a, and
the 'client' on machine b.  I'm running a ping-pong test: the client
sends a message to the server, the server receives that message and
responds back to the client.  They do this for 1024 messages, each 1KB
in size.

I'm seeing a huge disparity in the time of SAFE_MESS type messages and
the others:

UNRELIABLE_MESS: elapsed time is 2 second 562000 miliseconds
RELIABLE_MESS: elapsed time is 2 second 547000 miliseconds
FIFO_MESS: elapsed time is 2 second 547000 miliseconds
CAUSAL_MESS: elapsed time is 2 second 531000 miliseconds
AGREED_MESS: elapsed time is 2 second 547000 miliseconds
SAFE_MESS : elapsed time is 274 second 141000 miliseconds

Can anyone explain why it is so much slower?

Thanks.

Dan