obex transfer speeds

[Iain Hibbert]

Hi,

While obexapp is the subject, I wonder what kind of transfer speeds people
get?  Normally I use obexapp to copy files to and from my phone but they
are not much big files and I've never bothered with speed tests.. I have
been working some long hours at a tedious job lately and thought I would
listen to some music off my phone.

However, transferring tracks is tedious. I have calculated (see attached
program) that I'm getting about 12-15 kbytes/second by using windows
mobile bluetooth explorer in suck mode (navigate to my laptop, then copy
and paste the directory to the sd card)

using obexapp to push files seemed to go faster, about 15-20 kbytes/second
initially but obexapp doesn't handle sending complete directories so I had
to write a wrapper script and then when I left this going overnight it
only transferred about 15 tracks (I think a resource leak in the phone,
which needed a reboot afterwards)

So, my question is what kind of speeds should we normally expect with
OBEX?  I thought bluetooth should be faster than that but I don't really
know what version my phone has (laptop has Broadcom BCM2045B 2.0+EDR and
specs I found on the web says HTC Elf has 2.0 but I don't know about EDR)
and I only have a single computer so while a speed test would be possible
with two dongles, there could be interference in the stack. Has anybody
done anything like that in the past?

I read some comments previously on the list and have raised the MTU to
8192 bytes as suggested for an older obexapp but that hasn't improved the
speed much. Any other ideas?

regards,
iain
-------------- next part --------------
#include <bluetooth.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

const char *dev = "ubt0";

int
main(int ac, char *av[])
{
	struct bt_devinfo di;
	uint32_t c, r, s, dr, ds;

	if (ac > 1) {
		dev = av[1];
		ac--;
		av++;
	}

	if (ac > 1) {
		fprintf(stderr, "usage: %s [device]", getprogname());
		exit(EXIT_FAILURE);
	}

	c = 0;
	r = 0;
	s = 0;

	for (;;) {
		if (bt_devinfo(dev, &di) == -1)
			err(EXIT_FAILURE, "%s", dev);

		if (c++ == 0) {
			r = di.bytes_recv;
			s = di.bytes_sent;
		}

		dr = di.bytes_recv - r;
		r = di.bytes_recv;

		ds = di.bytes_sent - s;
		s = di.bytes_sent;

		fprintf(stdout, "\r%u recv, %u sent    ", dr, ds);

		fflush(stdout);
		sleep(1);
	}

	exit(EXIT_SUCCESS);
}