Hi, On Tue, Jun 28, 2011 at 10:52:55AM +0200, Eugen Leitl wrote: > ----- Forwarded message from William Salt <williamejs...@googlemail.com> ----- > From: William Salt <williamejs...@googlemail.com> > Date: Tue, 28 Jun 2011 08:03:25 +0100 > To: supp...@pfsense.com > Subject: [pfSense Support] Strange TCP connection behavior 2.0 RC2 (+3) > Reply-To: supp...@pfsense.com
> Each TCP connection starts very slowly, and will max out at around 190mbps, > taking nearly 2 minutes to climb to this speed before *plateauing*. > > We have to initiate many (5+) connections to saturate the link with tcp > connections with iperf. > ----- End forwarded message ----- You pretty much solved your own puzzle right there: the throughput on a single TCP connection will max out at the value determined by the bandwidth delay product (excluding other strange conditions, such as deep buffers). Here is a calculator online: http://www.switch.ch/network/tools/tcp_throughput/ -andreas [who has to explain this about once a week to customers who think that they bought a GigE connection but then can't "ftp" a file from coast to coast at 1Gbps throughput. Use multiple TCP streams!]
