sftp performance problem, cured by TCP_NODELAY

Rick Jones rick.jones2 at hp.com
Wed Jan 25 07:52:18 EST 2006

Miklos Szeredi wrote:
>>What sort of socket calling pattern was sftp making that had it
>>running into issues with Nagle and delayed ACK?
> Don't know exactly why Nagle kicks in,

In broad handwaving terms, applications that try to do "write write read" can 
run afoul of interactions between Nagle and delayed ACK.

> but it does so quite early, after just a couple of READ request/reply pairs.
> I can send you tcpdump output tomorrow.

Thanks.  I would like to see it.


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