🚀 go-pugleaf

Summary of the RPC wars to date:
    I posted a paper showing that Apollo RPC was slower than Sun RPC.
    Tony (of Netwise) posted a paper showing the same thing.
    Nat (of Apollo) pointed out that Sun's UDP based RPC used 8K packets
        which causes fragmentation to occur at the IP layer.  Apollo uses
        1K packets which never fragment. He says this fragmentation is a 
        major problem.
    Other folks pointed out that (in general) fragmentation is a bad thing.
    Brian et al. (of Sun) says that fragmentation is not a problem in most
        (or almost all) configurations, and thinks that Apollo is needlessly
        slowing everyone down to a least common denominator speed.

I have three comments on this:

    1. If for any reason UDP does not work, a person using Sun's RPC system
       can use TCP.  (This option is not available to Apollo's RPC users,
       but is available to Netwise RPC users.)  Except for very small packets
       Sun's TCP based RPC protocol is faster than Apollo's RPC protocol.

       Because of the differences in reliability described in my paper,
       I always compare Apollo to Sun TCP.  Since they are both equally
       reliable I think this is the fairest comparison.  

    2. The fragmentation which Nat is worried about is happening at the IP
       layer, which is two protocol layers below RPC.  I think it is
       unfair to blame the RPC implementor for fragmentation which is 
       happening outside of his control in the protocol stack.  I might 
       complain to Sun's UDP implementation group about the fragmentation, 
       but not to their RPC group.

    3. Apollo is much slower than Sun:

           For half K packets Sun TCP is about the same speed as Apollo.
           For 8K packets Sun TCP is about three times faster than Apollo.
           For 16K packets Sun TCP is about four times faster than Apollo.

The exact numbers are in my paper.  If you want a copy look through the back 
issues of comp.misc, or email me.  I respond to all email, so if you have not 
heard from me, try again with a different path, or give me a call.

Joshua Levy
--------                Quote: "You can stand me up at the gates of Hell,
Addresses:                      but I wont back down!"  -- Tom Petty
joshua@atherton.com          
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