Nagle & delayed ACK strike again

[Rick Jones]

>>My personal stance is that 99 times out of ten, if an end-user 
>>application speeds-up when it sets TCP_NODELAY, it implies the end-user 
>>application is broken and sending "logically associated" data in 
>>separate send calls.
> 
> 
> You tell me, is X protocol broken?  

Likely not - the discrete mouse events which are usually cited as the 
reason X needs TCP_NODLEAY are not logically associated.  Hence that is 
the 100th situation out of 10 rather then the 99.

> Is SFTP broken? 

Depends - is it writing logically associated data to the connection in 
more than one send call?

> I don't think
> SFTP more broken than any other network fs protocol.  The slowdown
> happens with a stream of WRITE requests and replies.  If the requests
> weren't acknowledged, there wouldn't be any trouble, but
> acknowledgements do make sense for synchronous operation.

Do you have some system call traces and/or packet traces we could look 
at?  If the write requests and replies are each single send call they 
probably qualify as the "X exception"

rick jones