Hi Andy, the behavior I thought I was seeing was exactly the opposite of what I would have expected - with Nagle turned on it was faster even though the request messages were likely delayed sender side. Anyways, it does not matter because the `TCP_NODELAY` flag is the one responsible for Nagle, and `O_NDELAY` which I was using by mistake is equivalent to `O_NONBLOCK`. Cheers, Lukasz --- Reply to this email directly or view it on GitHub: https://github.com/xrootd/xrootd/issues/20#issuecomment-25516874 ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the XROOTD-DEV list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=XROOTD-DEV&A=1