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Re: [remote protocol] support for disabling packet acknowledgement


>>>>> "Pedro" == Pedro Alves <pedro@codesourcery.com> writes:

 Pedro> Hi, This patch adds support to the remote protocol to disable
 Pedro> packet acknowlegment.  This is useful when the transport being
 Pedro> used is itself reliable, e.g., TCP/IP.  In these cases, by
 Pedro> removing the acking we reduce the amount of roundtrips, and
 Pedro> decrease the communication latency.

I'm not sure this is a good idea.

For one thing, if you want to work on performance, there are much more
dramatic changes to the protocol that could be done that would help
much more.  I can't believe that the cost of acks is significant
compared to all the other bottlenecks.

Also, TCP is reliable delivery at the transport layer.  It doesn't do
reliable delivery at the application layer -- that's what the gdb
remote protocol ACKs do.  The fact that TCP delivered a packet to the
stub doesn't mean the stub acted on it.

     paul


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