re: [PATCH] new timeout behavior for RPC requests on TCP sockets

[Dan Kegel]

Chuck wrote:
> make RPC timeout behavior over TCP sockets behave more like reference
> client implementations.  reference behavior is to transmit the same
> request three times at 60 second intervals; if there is no response, close
> and reestablish the socket connection.  we modify the Linux RPC client as
> follows:
> 
> +  after a minor retransmit timeout, use the same timeout value when
>    retrying on a TCP socket rather than doubling the value
> +  after a major retransmit timeout, close the socket and attempt
>    to reestablish a fresh TCP connection
> 
> note that today mount uses a 6 second timeout with 5 retries for NFS over
> TCP by default; proper default behavior is 2 retries each with 60 second
> timeouts.  a separate patch for mount is pending.

Chuck, can you briefly explain why RPC does any minor
retransmits at all over TCP?
Shouldn't TCP's natural retransmit take care of that?
- Dan