in testing tap(4) performance on the same box with the following config
using claudios userlandbridge (tbridge) in between two tap interfaces
each tap was also added their own standard bridge(4) along with 1 physical
interface.
iperf3client--ix0--bridge0--tap0--tbridge--tap1--bridge1--ix1---iperf3svr
with a 1socket 2 core system that gives 3Gb/s we got the following
performance
tbridge -t gave 557Mb/s TCP throughput
btw (tbridge -t did not stop after using ^C or kill
but did respond to kill -s SIGKILL )
tbridge -s gave 455Mb/s TCP throughput
tbridge -p gave 448Mb/s TCP throughput
tbridge -k gave 458mb/s TCP througput
im going to try this again with more CPUs as the workload of forwarding in
this box involves 3 bridges in series.
I will also try with the tpmr(4) driver
so something about OpenVPN has a bottleneck that reduces performance
by a factor of 3 -4x
-- Forwarded message -
From: Tom Smyth
Date: Tue, 21 Jan 2020 at 11:15
Subject: Re: tap(4) performance tuning on (amd64)
To: Tom Smyth , Misc
Thanks Claudio,
the program now seems to run without exiting ... Ill do some tests
and get back to you
later
Tom Smyth
On Tue, 21 Jan 2020 at 03:09, Claudio Jeker
wrote:
>
> On Tue, Jan 21, 2020 at 02:44:35AM +, Tom Smyth wrote:
> > Claudio,
> > Thanks for this,
> > I compiled it on Openbsd 6.6 (stable) amd64
> >
> > it compiled without error
> >
> > the binary seems to run fine but,
> > ./tbridge -k /dev/tap0 /dev/tap1
> >
> > runs and displays the usage message and gives an errorlevel of 1
> > every time use the -k or -t or -s or -p arguments see terminal
> > conversation below
> >
>
> Shit, I added a last minute check and as usual introduced a bug.
> Line 189 change if (ch != 0) to if (mode != 0)
>
> --
> :wq Claudio
>
> /*
> * Copyright (c) 2020 Claudio Jeker
> *
> * Permission to use, copy, modify, and distribute this software for any
> * purpose with or without fee is hereby granted, provided that the above
> * copyright notice and this permission notice appear in all copies.
> *
> * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
WARRANTIES
> * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
> * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
> * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
> * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
> * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
> * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
> */
> #include
> #include
> #include
>
> #include
> #include
> #include
> #include
> #include
> #include
> #include
> #include
> #include
> #include
>
> volatile sig_atomic_tquit;
>
> static void
> do_read(int in, int out)
> {
> char buf[2048];
> ssize_t n, o;
>
> n = read(in, buf, sizeof(buf));
> if (n == -1)
> err(1, "read");
> o = write(out, buf, n);
> if (o == -1)
> err(1, "read");
> if (o != n)
> errx(1, "short write");
> }
>
> static void
> do_poll(int fd[2])
> {
> struct pollfd pfd[2];
> int n, i;
>
> while (quit == 0) {
> memset(pfd, 0, sizeof(pfd));
> pfd[0].fd = fd[0];
> pfd[0].events = POLLIN;
>
> pfd[1].fd = fd[1];
> pfd[1].events = POLLIN;
>
> n = poll(pfd, 2, INFTIM);
> if (n == -1)
> err(1, "poll");
> if (n == 0)
> errx(1, "poll: timeout");
> for (i = 0; i < 2; i++) {
> if (pfd[i].revents & POLLIN)
> do_read(fd[i], fd[(i + 1) & 0x1]);
> else if (pfd[i].revents & (POLLHUP | POLLERR))
> errx(1, "fd %d revents %x", i,
pfd[i].revents);
> }
> }
>
> }
>
> static void
> do_select(int fd[2])
> {
> fd_set readfds;
> int n, i, maxfd = -1;
>
> while (quit == 0) {
> FD_ZERO();
> for (i = 0; i < 2; i++) {
> if (fd[i] > maxfd)
> maxfd = fd[i];
> FD_SET(fd[i], );
> }
> n = select(maxfd + 1, , NULL, NULL, NULL);
> if (n == -1)
> err(1, "select");
> if (n == 0)
> errx(1, "select: timeout");
> for (i = 0; i < 2; i++) {
> if (FD_ISSET(fd[i], ))
> do_read(fd[i], fd[(i + 1) & 0x1]);
> }
> }
> }
>
> static void
> do_kqueue(int fd[2])
> {
> struct kevent kev[2];
> int kq, i, n;
>
> if ((kq = kqueue()) == -1)
> err(1,
