Mike Cronenworth wrote:
-------- Original Message -------- Subject: Re: bluetooth 2.0 is extremely slow From: Mike Cronenworth mike@cchtml.com To: mike@cchtml.com, Development discussions related to Fedora fedora-devel-list@redhat.com Cc: Bastien Nocera bnocera@redhat.com Date: 04/09/2008 09:53 PM
OK,
I applied the attached patch. I'm putting this up for review, and any suggestions (should this be posted somewhere else, etc.). My transfer time went from 40 seconds to 10 seconds. It now matches Windows XP performance. Just add it to the RPM spec like the existing patches.
Regards, Michael
After further testing I've created a proper patch. These are my results based on the attached patch. Each MTU was tested twice using "open_push" as the receiver program and using the "gnome-obex-server" program.
Bluetooth 2.0 - 1070k file transfer from phone to computer 1024 MTU - 40 seconds (default MTU) 8192 MTU - 20 seconds 16384 MTU - 10 seconds 32768 MTU - 11 seconds 65535 MTU - 12 seconds
Bluetooth 1.1 - 1070k file transfer from phone to computer 1024 MTU - 52 seconds (default MTU) 8192 MTU - 30 seconds 16384 MTU - 34 seconds
I revised the patch to not change the minimum MTU. It had no effect on speeds. 16k seems to be the sweet spot. This makes *huge* differences for both 1.1 and 2.0. It seems no one with OpenOBEX bothered to test transfer speeds... kind of unsettling. I will make a Bugzilla report and join the bluez list later today.
Regards, Mike
Does using OBEX_SetTransportMTU() help? http://www.zuckschwerdt.org/apidocs/r323.html