Re: OPP throughput is low in ubuntu 18.04

[Amit K Bag <amit.k.bag@intel.corp-partner.google.com>]

Hello Luiz,

I am not sure what changes in kernel causing low throughput. If I get
any clue I will let you know.
I wil lalso test your patch with linux - linux and update the result.

On Fri, Feb 14, 2020 at 6:18 AM Luiz Augusto von Dentz
<luiz.dentz@gmail.com> wrote:
>
> Hi Amit,
>
> On Thu, Feb 13, 2020 at 3:32 AM Amit K Bag
> <amit.k.bag@intel.corp-partner.google.com> wrote:
> >
> > Hello Luiz,
> >
> > I tested with the patch you have mentioned but not getting any better
> > throughput.
> > Please have a look at the log attached.
> >
> > We are using below configuration for linux
> > - Kernel : 4.19.102
> > - OS : ubuntu 18.04.2 LTS
> > - Bluez -5.48
> >
> > For other machine we are using windows
>
> I think there is some work to be done to work with RFCOMM since we are
> only doing this for L2CAP, I will have a look later this week, btw
> have you look into any difference we may have between these kernels?
> Or actually in what combination they appear because there could be an
> isolated problem in either the kernel or the userspace changes.
>
> > On Mon, Feb 10, 2020 at 11:03 PM Luiz Augusto von Dentz
> > <luiz.dentz@gmail.com> wrote:
> > >
> > > Hi Amit,
> > >
> > > On Mon, Feb 10, 2020 at 3:20 AM Amit K Bag
> > > <amit.k.bag@intel.corp-partner.google.com> wrote:
> > > >
> > > > Hello All,
> > > >
> > > > I am tring to test the OPP throughput in linux.
> > > > I transferred between 2 machines having ubuntu 16.04 with bluez
> > > > version 5.44 in that I am getting 1.4mbps speed.
> > > >
> > > > Kernel : 4.14.13
> > > > OS : ubuntu 18.04.2 LTS
> > > > Bluez -5.44
> > > >
> > > > I am using a 12 MB of audio file.
> > > > But the same file when I transferred between  2 machines having ubuntu
> > > > 18.04 the speed is significantly reduced.
> > > >
> > > > Kernel : 4.18.0-15-generic
> > > > OS : ubuntu 18.04.2 LTS
> > > > Bluez -5.48
> > > >
> > > > Could someone tell me why its reduced in ubuntu 18.04
> > >
> > > I don't think we change anything on Obexd related to that so perhaps
> > > it is something related to the L2CAP MTU? We could try setting the MTU
> > > to 0 so it automatically picks the matching MTU if you do have the
> > > following patch applied to your kernel:
> > >
> > > Bluetooth: Auto tune if input MTU is set to 0
> > >
> > >
> > > --
> > > Luiz Augusto von Dentz
>
>
>
> --
> Luiz Augusto von Dentz