Hello Arno, >> By default winsock's send buffer size is 8 kb which is much bigger >> than TFtpCli's constant BLOCK_SIZE of 1460 bytes. So one condition >> described in the article is not true since a single send call in >> TFtpCli does not fill the whole underlying winsock send buffer. >> I realy wonder why disabling Nagle doesn't help? > > Same applies to WSocket's internal send buffer that has a block size > of 1460 as well. So if you haven't increased BufSize of TWSocket > a single send call does never fill the whole underlying winsock send > buffer.
That's exactly the thing I'm doing at the moment: I increase the BufSize of TWSocket from 1460 bytes to 1MB. The throughput increases from 1.2MB/s to more than 7MB/s. As far as I understand Nagle=off only would help me if I would like to send small packets (< MCU) at a very high rate. But that is not the case: I want to deliver large files (> 3GB). When I look at the IP traffic with Wireshark I see something like this in the case where TWSocket.BufSize=1460 : Client->Server 1448 bytes Client->Server 12 bytes Server->Client ACK Client->Server 1448 bytes Client->Server 12 bytes Server->Client ACK .... And in the case where TWSocket.BufSize=1MB : Client->Server 1448 bytes Client->Server 1448 bytes Client->Server 1448 bytes // previous line repeated 10-30 times Server->Client ACK Client->Server 1448 bytes Client->Server 1448 bytes Client->Server 1448 bytes // previous line repeated 10-30 times Server->Client ACK .... >>> So shall I explicitly add a call setsockopt() that increases the >>> socket send buffer dramatically (>1MB)? >> Use WSocket option SocketSndBufSize instead, it will the call >> setsockopt() internally. I think that 1 MB is much too big, since >> this memory is allocated from kernel memory which is not an endless >> resource. SocketSndBufSize property is read-only, at least in my version of WSocket.pas (V5.25). /Tobias -- NOA Audio Solutions Vertriebsges.m.b.H. Tel: +43-1-5452700 Johannagasse 42/4 Fax: +43-1-545270014 A - 1050 Wien Www: http://www.noa-audio.com -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
