Mailing List Archive

2005 laptop stutters after upgrade from 0.27 to 0.28
Yep, I've still got a few old laptops that have been working quite well
as frontends. But one isn't performing quite as well with mythtv 0.28
and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu 12.04. So,
I'm trying to understand why, and whether there's anything I can do to
get it to perform running 0.28 as well as it does running 0.27. The
laptop and the master backend have multiple boot partitions, so that's
how I switch back and forth between 0.27 and 0.28

I see slight but noticeable stuttering during panning scenes when I
playback standard definition H.264 video on 0.28 but not when I play
back the same video on 0.27. It's not CPU bound, the CPU hovers around
30% to 35% on both versions and might be using a tad less CPU on 0.28 as
it does on 0.27.

The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz CPU
and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller. The
display is 1280x800 resolution. It's configured to use the Slim playback
profile on both 0.27 and 0.28, as defined in the database migrated from
0.27 to 0.28.

I have compared mythfrontend logs using -v general,playback at the
default info level. I can see no meaningful difference in the log
output. I've hesitated to try the debug level, for fear that might push
the CPU and/or disk to work too hard, although maybe that should be my
next step?

I have compared Xorg.0.log on both OSs, and only see slight differences
like version numbers, and a handful of different messages that I suspect
are due to logging changes in source and not meaningful.

FWIW, the laptop can play 720p and 1080i MPEG2 transport streams
smoothly in both 0.27 and 0.28. But it cannot play high definition H.264
content on either, where it's definitely CPU bound. I've also got a
couple of circa 2004 thinkpads with Pentium M CPUs and Radeon GPUs that
CAN handle the SD H.264 in both 0.27 and 0.28 environments. It's just
this Dell that's keeping me from cutting over to 0.28.

Has anyone else noticed a degradation in performance on older hardware
after upgrading?

Any suggestions on how to identify the cause, e.g. OS module, X driver
or mythtv?

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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 07/06/17 08:09, faginbagin wrote:
> Yep, I've still got a few old laptops that have been working quite
> well as frontends. But one isn't performing quite as well with mythtv
> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
> 12.04. So, I'm trying to understand why, and whether there's anything
> I can do to get it to perform running 0.28 as well as it does running
> 0.27. The laptop and the master backend have multiple boot partitions,
> so that's how I switch back and forth between 0.27 and 0.28
>
> ...snip...
>
> Has anyone else noticed a degradation in performance on older hardware
> after upgrading?
>
> Any suggestions on how to identify the cause, e.g. OS module, X driver
> or mythtv?
>
> _______________________________________________
>

Just brainstorming a bit here:
- was the 16.04 install a clean install or a dist-upgrade from 12.04? If
clean install have you checked the judder free and frame display timing
steps again? https://www.mythtv.org/wiki/User_Manual:JudderFree and
https://www.mythtv.org/wiki/Frame_display_timing
- maybe try cutting mythtv out of the equation for a bit. Move a
recording to local drive and compare playback in VLC using both 12.04
and 16.04 and look for any differences.
- maybe try a "complex" transcode on the local test file using ffmpeg on
both 12.04 and 16.04 to see if that shows a significant difference or
not (something to make the laptop sweat / work hard so small differences
might be more readily noticed).
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 07/06/17 00:36, Mark Perkins wrote:
>
>
> On 07/06/17 08:09, faginbagin wrote:
>> Yep, I've still got a few old laptops that have been working quite
>> well as frontends. But one isn't performing quite as well with mythtv
>> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
>> 12.04. So, I'm trying to understand why, and whether there's anything
>> I can do to get it to perform running 0.28 as well as it does running
>> 0.27. The laptop and the master backend have multiple boot partitions,
>> so that's how I switch back and forth between 0.27 and 0.28
>>
>> ...snip...
>>
>> Has anyone else noticed a degradation in performance on older hardware
>> after upgrading?
>>
>> Any suggestions on how to identify the cause, e.g. OS module, X driver
>> or mythtv?
>>
>> _______________________________________________
>>
>
> Just brainstorming a bit here:
> - was the 16.04 install a clean install or a dist-upgrade from 12.04? If
> clean install have you checked the judder free and frame display timing
> steps again? https://www.mythtv.org/wiki/User_Manual:JudderFree and
> https://www.mythtv.org/wiki/Frame_display_timing
> - maybe try cutting mythtv out of the equation for a bit. Move a
> recording to local drive and compare playback in VLC using both 12.04
> and 16.04 and look for any differences.
> - maybe try a "complex" transcode on the local test file using ffmpeg on
> both 12.04 and 16.04 to see if that shows a significant difference or
> not (something to make the laptop sweat / work hard so small differences
> might be more readily noticed).

Pull up the playback OSD (from memory m > playback > playback data)
and keep an eye on the frames decoded figures, that should stay as
high as possible

Regards
Stuart

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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On Tue, 2017-06-06 at 18:39 -0400, faginbagin wrote:
> Yep, I've still got a few old laptops that have been working quite
> well 
> as frontends. But one isn't performing quite as well with mythtv
> 0.28 
> and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu 12.04.

Been there, done that.

> The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz
> CPU 
> and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller.

In my case it was good old, tried and true Nvidia ION.

> Has anyone else noticed a degradation in performance on older
> hardware 
> after upgrading?

So, yes, most definitely.

> Any suggestions on how to identify the cause, e.g. OS module, X
> driver 
> or mythtv?

I'm afraid not. That performance problem was the last straw for me and
was what I finally needed to jump head first into using Kodi instead of
the MythFE.

I have not looked back.

As for my experience with Kodi as a replacement for the MythFE, I did
use the Kodi Myth pvr plugin for a while but it caused Kodi to be
unstable, needing restarting every few days.

I have since then abandoned using that plugin and just started
exporting all recordings from Myth to the Kodi storage group as soon as
they were done, using a post-recording hook/job.

Hopefully you can get the performance issue worked out.

Cheers,
b.
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On Tue, 2017-06-06 at 23:36 +0000, Mark Perkins wrote:
>
> Just brainstorming a bit here:
> - was the 16.04 install a clean install or a dist-upgrade from 12.04?

Mine was a dist-upgrade.

> - maybe try cutting mythtv out of the equation for a bit. Move a 
> recording to local drive and compare playback in VLC using both
> 12.04 
> and 16.04 and look for any differences.

Indeed. Rather, I used Kodi as my o/s&hardware test. Kodi had
absolutely no problem playing exactly the same files that the MythFE
was having trouble with with.

Cheers,
b.
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
Nothing helpful to add for how to fix it, but I have been experiencing
stuttering on my ION remote frontends. I get audio+video stuttering on my
ION and audio only on my ION 2.

I've ruled out all the tweaaks that have worked in the past; xorg config
tweaks, reducing the VDPAU playback profiles, and making sure audio buffers
are high enough. Nothing in the logs to indicate an issue, I may need to
adjust logging levels.

I see this on both Mythbuntu upgrades and Xubuntu fresh install, I'm
running 17.04 on both with the latest MythTV packages from the Mythbuntu
PPA.
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On Wed, 2017-06-07 at 14:46 +0000, john.baab@gmail.com wrote:
>
> I've ruled out all the tweaaks that have worked in the past; xorg
> config
> tweaks, reducing the VDPAU playback profiles, and making sure audio
> buffers
> are high enough.  Nothing in the logs to indicate an issue, I may
> need to
> adjust logging levels.

Try Kodi just to validate that your O/S and hardware are still
functioning and capable of playing the same content.

Cheers,
b.
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 06/06/2017 06:39 PM, faginbagin wrote:
> Yep, I've still got a few old laptops that have been working quite
> well as frontends. But one isn't performing quite as well with mythtv
> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
> 12.04. So, I'm trying to understand why, and whether there's anything
> I can do to get it to perform running 0.28 as well as it does running
> 0.27. The laptop and the master backend have multiple boot partitions,
> so that's how I switch back and forth between 0.27 and 0.28
>
> I see slight but noticeable stuttering during panning scenes when I
> playback standard definition H.264 video on 0.28 but not when I play
> back the same video on 0.27. It's not CPU bound, the CPU hovers around
> 30% to 35% on both versions and might be using a tad less CPU on 0.28
> as it does on 0.27.
>
> The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz CPU
> and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller. The
> display is 1280x800 resolution. It's configured to use the Slim
> playback profile on both 0.27 and 0.28, as defined in the database
> migrated from 0.27 to 0.28.
>
> I have compared mythfrontend logs using -v general,playback at the
> default info level. I can see no meaningful difference in the log
> output. I've hesitated to try the debug level, for fear that might
> push the CPU and/or disk to work too hard, although maybe that should
> be my next step?
>
> I have compared Xorg.0.log on both OSs, and only see slight
> differences like version numbers, and a handful of different messages
> that I suspect are due to logging changes in source and not meaningful.
>
> FWIW, the laptop can play 720p and 1080i MPEG2 transport streams
> smoothly in both 0.27 and 0.28. But it cannot play high definition
> H.264 content on either, where it's definitely CPU bound. I've also
> got a couple of circa 2004 thinkpads with Pentium M CPUs and Radeon
> GPUs that CAN handle the SD H.264 in both 0.27 and 0.28 environments.
> It's just this Dell that's keeping me from cutting over to 0.28.
>
> Has anyone else noticed a degradation in performance on older hardware
> after upgrading?
>
> Any suggestions on how to identify the cause, e.g. OS module, X driver
> or mythtv?
>
> _______________________________________________

Does your laptop setup support OpenGL? You could try an OpenGL playback
profile, that may be smoother. (if it works - I had a Dell laptop from
2007 with Nvidia and turning on OpenGL caused the entire system to
freeze.). Note that if you turn on OpenGL playback profile you must also
select OpenGL for the Theme Painter.

It may be the same problem as https://code.mythtv.org/trac/ticket/12907
. That is on Raspberry Pi, but I think the problem will happen with
systems with less power. I think it is caused by the amount of
processing between frames. I plan to look into whether this cam be
reduced so as to minimize the jumpiness.

Peter
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
I do see these in the logs on both:
Video sync method can't support double framerate (refresh rate too low for
2x deint)
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/6/2017 7:36 PM, Mark Perkins wrote:
> On 07/06/17 08:09, faginbagin wrote:
>> Yep, I've still got a few old laptops that have been working quite
>> well as frontends. But one isn't performing quite as well with mythtv
>> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
>> 12.04. So, I'm trying to understand why, and whether there's anything
>> I can do to get it to perform running 0.28 as well as it does running
>> 0.27. The laptop and the master backend have multiple boot partitions,
>> so that's how I switch back and forth between 0.27 and 0.28
>>
>> ...snip...
>>
>> Has anyone else noticed a degradation in performance on older hardware
>> after upgrading?
>>
>> Any suggestions on how to identify the cause, e.g. OS module, X driver
>> or mythtv?
>>
>> _______________________________________________
>>
>
> Just brainstorming a bit here:
> - was the 16.04 install a clean install or a dist-upgrade from 12.04?
It was a clean install, although the laptop has been represented in the
database since 2011, which I think was when my setup was running 0.24.

> If clean install have you checked the judder free and frame display timing
> steps again? https://www.mythtv.org/wiki/User_Manual:JudderFree and
> https://www.mythtv.org/wiki/Frame_display_timing
> - maybe try cutting mythtv out of the equation for a bit. Move a
> recording to local drive and compare playback in VLC using both 12.04
> and 16.04 and look for any differences.
> - maybe try a "complex" transcode on the local test file using ffmpeg on
> both 12.04 and 16.04 to see if that shows a significant difference or
> not (something to make the laptop sweat / work hard so small differences
> might be more readily noticed).

Not sure I understand what you mean by "complex" transcode. Can you
elaborate?

Many thanks to you and everyone who has replied to this thread. It will
be a while before I get to follow up on them. I'll report back with my
findings. I sure hope it's something that can be fixed with the right
configuration tweak.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/7/2017 10:46 AM, john.baab@gmail.com wrote:
> Nothing helpful to add for how to fix it, but I have been experiencing
> stuttering on my ION remote frontends. I get audio+video stuttering on
> my ION and audio only on my ION 2.
>
> I've ruled out all the tweaaks that have worked in the past; xorg config
> tweaks, reducing the VDPAU playback profiles, and making sure audio
> buffers are high enough. Nothing in the logs to indicate an issue, I
> may need to adjust logging levels.
>
> I see this on both Mythbuntu upgrades and Xubuntu fresh install, I'm
> running 17.04 on both with the latest MythTV packages from the Mythbuntu
> PPA.

Hmm, I, the OP, also have an ION system that works fine on both 0.27 and
0.28, an Acer Aspire Revo 3610. There have been hiccups in the past, the
last one was due to a nvidia driver bug that didn't allow vdpau unless
you were root. But that was fixed by either rolling back to the previous
version or upgrading to the next major nvidia driver release.

I think one reason why my ION is still serving me well is because it's
connected to a 720p TV, with a 1280x720 resolution. I think it would
struggle if it had to drive a 1920x1080p resolution display.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 9 June 2017 at 16:47, faginbagin <mythtv@hbuus.com> wrote:

> On 6/7/2017 10:46 AM, john.baab@gmail.com wrote:
>
>> Nothing helpful to add for how to fix it, but I have been experiencing
>> stuttering on my ION remote frontends. I get audio+video stuttering on my
>> ION and audio only on my ION 2.
>>
>> I've ruled out all the tweaaks that have worked in the past; xorg config
>> tweaks, reducing the VDPAU playback profiles, and making sure audio buffers
>> are high enough. Nothing in the logs to indicate an issue, I may need to
>> adjust logging levels.
>>
>> I see this on both Mythbuntu upgrades and Xubuntu fresh install, I'm
>> running 17.04 on both with the latest MythTV packages from the Mythbuntu
>> PPA.
>>
>
> Hmm, I, the OP, also have an ION system that works fine on both 0.27 and
> 0.28, an Acer Aspire Revo 3610. There have been hiccups in the past, the
> last one was due to a nvidia driver bug that didn't allow vdpau unless you
> were root. But that was fixed by either rolling back to the previous
> version or upgrading to the next major nvidia driver release.
>
> I think one reason why my ION is still serving me well is because it's
> connected to a 720p TV, with a 1280x720 resolution. I think it would
> struggle if it had to drive a 1920x1080p resolution display.
>
> My Zotac ZBOX-ID31DVD works fine at 1920x1200 using the "VDPAU High
Quality" playback profile and plays pretty much anything I throw at it.

although its a Next Gen ION

http://old.zotac.com/en/products/mini-pcs/zbox-dvd/product/zbox-dvd/detail/zbox-dvd-id31/sort/starttime/order/DESC/amount/10/section/specifications.html

sorry cant offer many suggestions on your Dell issue, perhaps its related
to your Xorg.conf?

once again I'd highly recommend the JudderFree Playback wiki article
https://www.mythtv.org/wiki/User_Manual:JudderFree

Cheers,

Anthony
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On Friday, June 9, 2017 08:47 CEST, faginbagin <mythtv@hbuus.com> wrote:
 ...

Hmm, I, the OP, also have an ION system that works fine on both 0.27 and
0.28, an Acer Aspire Revo 3610. There have been hiccups in the past, the
last one was due to a nvidia driver bug that didn't allow vdpau unless
you were root. But that was fixed by either rolling back to the previous
version or upgrading to the next major nvidia driver release.

...
...I have been following this thread with interest, as I have also been suffering from stuttering problems since upgrading to .28. Up to now, I saw little point in interrupting with "Me too!"

However, I am very interested in faginbagin's remark about vdpau. I was not aware of this but have certainly been under the impression that the problem was due to interactions between mythtv and the nvidia driver.

I'm running on AMD opteron dual core (around 3GHz if I remember) and Nvidia GT610. A combination that was giving perfectly smooth playback up to my Ubuntu and 0.27-0.28 upgrade towards the end of last year.

The system did briefly seem to be stable and stutter free again around year-change 2016-2017 running nvidia v. 340.x (can't remember the minor version from here). Some time after that, my system started to stutter again, I think after apt upgrade pushed a minor nvidia version update - I should have been more awake at the time.

As the GT610 was a relatively popular choice at the time, it would be really good if we could together work out and publicise a recommended way to set up recent versions of MythTV with nvidia drivers covering that range of devices - in my case and for other ex-mythbuntu users it would also be good if we could bring Ubuntu into the mix when describing how to do this.

Please let me know if there's anything I can do in my now quite limited time, to provide logs or other bug-tracking info.

Best Regards

Marius





 
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On Fri, 2017-06-09 at 02:47 -0400, faginbagin wrote:
>
> Hmm, I, the OP, also have an ION system that works fine on both 0.27
> and 
> 0.28, an Acer Aspire Revo 3610.

That is *exactly* the system I had my post-ubuntu-mythtv upgrade
performance problems.

But the overriding point here is that on the exact same machine, no
changes, Kodi plays everything fine. So that is validating the O/S,
drivers, hardware, etc.

b.
Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
> On Jun 9, 2017, at 7:37 AM, Brian J. Murrell <brian@interlinx.bc.ca> wrote:
>
> On Fri, 2017-06-09 at 02:47 -0400, faginbagin wrote:
>>
>> Hmm, I, the OP, also have an ION system that works fine on both 0.27
>> and
>> 0.28, an Acer Aspire Revo 3610.
>
> That is *exactly* the system I had my post-ubuntu-mythtv upgrade
> performance problems.
>
> But the overriding point here is that on the exact same machine, no
> changes, Kodi plays everything fine. So that is validating the O/S,
> drivers, hardware, etc.
>
> b.

An additional point of information for vdpau, though it isn’t nvidia, rather it is an amd Hudson E-350 dual core processor in a foxconn NT-3500 nettop computer.

It is running ubuntu 16.04 and mythtv.29-fixes and the only time it stutters is when there is an overlay. otherwise, 1080i, 1080p, 720p video is just fine on it using mythtv!

regards!
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/7/2017 10:21 PM, john.baab@gmail.com wrote:
> I do see these in the logs on both:
> Video sync method can't support double framerate (refresh rate too low
> for 2x deint)

I don't think that's a problem. I see that whenever I play mpeg2 720p
video, even though the video plays just fine.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/7/2017 10:46 AM, john.baab@gmail.com wrote:
> Nothing helpful to add for how to fix it, but I have been experiencing
> stuttering on my ION remote frontends. I get audio+video stuttering on
> my ION and audio only on my ION 2.
>
> I've ruled out all the tweaaks that have worked in the past; xorg config
> tweaks, reducing the VDPAU playback profiles, and making sure audio
> buffers are high enough. Nothing in the logs to indicate an issue, I
> may need to adjust logging levels.
>
> I see this on both Mythbuntu upgrades and Xubuntu fresh install, I'm
> running 17.04 on both with the latest MythTV packages from the Mythbuntu
> PPA.

One thing I just remembered that might help is to double check how much
memory is given to video in the BIOS. On my Acer Aspire Revo 3610, it's
set under:
Advanced Chipset Features -> UMA Frame Buffer Size

The default setting is Auto, which for my system with 2GB translates to
256MB. The max I can set it to is 512MB. It makes a difference playing
HD video. A couple of years ago, the CMOS battery failed and whenever
there was a power outage, I had trouble playing HD video until I went
into the BIOS and fixed that setting. I finally took the machine apart,
gave it a good cleaning and replaced the battery. It's been fine since.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/9/2017 7:10 AM, Marius Schrecker wrote:
>
> On Friday, June 9, 2017 08:47 CEST, faginbagin <mythtv@hbuus.com> wrote:
>> ...
>>
>> Hmm, I, the OP, also have an ION system that works fine on both 0.27 and
>> 0.28, an Acer Aspire Revo 3610. There have been hiccups in the past, the
>> last one was due to a nvidia driver bug that didn't allow vdpau unless
>> you were root. But that was fixed by either rolling back to the previous
>> version or upgrading to the next major nvidia driver release.
>>
>> ...
>> ...
> I have been following this thread with interest, as I have also been
> suffering from stuttering problems since upgrading to .28. Up to now, I
> saw little point in interrupting with "Me too!"
>
> However, I am very interested in faginbagin's remark about vdpau. I was
> not aware of this but have certainly been under the impression that the
> problem was due to interactions between mythtv and the nvidia driver.
>
> I'm running on AMD opteron dual core (around 3GHz if I remember) and
> Nvidia GT610. A combination that was giving perfectly smooth playback up
> to my Ubuntu and 0.27-0.28 upgrade towards the end of last year.
>
> The system did briefly seem to be stable and stutter free again around
> year-change 2016-2017 running nvidia v. 340.x (can't remember the minor
> version from here). Some time after that, my system started to stutter
> again, I think after apt upgrade pushed a minor nvidia version update -
> I should have been more awake at the time.
>
> As the GT610 was a relatively popular choice at the time, it would be
> really good if we could together work out and publicise a recommended
> way to set up recent versions of MythTV with nvidia drivers covering
> that range of devices - in my case and for other ex-mythbuntu users it
> would also be good if we could bring Ubuntu into the mix when describing
> how to do this.
>
> Please let me know if there's anything I can do in my now quite limited
> time, to provide logs or other bug-tracking info.
>
> Best Regards
>
> Marius

Hi Marius,

In case it helps, I've got a mix of nvidia GPUs:

The GT430 and GT520 have 1GB ram. They use the "VDPAU High Quality"
playback profile and are driving 1920x1080p TVs. The system with the
GT520 is both a frontend and a master backend.

The 8400GS has 256MB and the ION has 512MB. These two low end gpus use
the "VDPAU Slim" profile and are driving 1280x720p TVs. The ION is
paired with an Intel Atom 330 CPU, which is the slowest CPU paired with
an nvidia GPU. The system with the 8400GS is both a frontend and a slave
backend and is paired with an Athlon II X4 635 2.9GHz CPU. I think it's
a safe bet that your GT610 is more capable than my 8400GS.

All are using the nvidia-340 package on mythtv 0.27, mythbuntu 12.04.
They all had nvidia-304 installed originally, but I upgraded them to
nvidia-340 when there was a buggy point release of nvidia-304. I think
that was Summer 2016.

On mythtv 0.28, mythbuntu 16.04, the low end gpus are using the
nvidia-340 package. Looking back at the dpkg logs, that's what was
automatically installed. But the systems with the GT430 and GT520 have
gone through three different nvidia packages. When first installed, they
had nvidia-361. In the Nov-Dec 2016 time range, they were upgraded to
nvidia-367. In the March-May 2017 time range, they were upgraded to
nvidia-375. I don't recall doing these upgrades, I believe they were
done automatically. I assume the low end GPUs are using nvidia-340
because the newer packages don't support them.

And they all seem to be working fine. It's just the 2005 laptop that's
keeping me from upgrading to mythtv 0.28, mythbuntu 16.04.

For what it's worth, I try to apply the latest updates to each computer
about once a month. But before I do, I always make a full backup.
They're all set up to multiboot current and new versions, or old and
current versions, so it's easy to make a full offline backup using tar.
And I've had to restore those backups on more than one occasion.
Whenever I upgrade to a new O/S and mythtv version, I never do a
dist-upgrade, I always do a clean install in the old partition. It takes
more time to get everything configured, but I think I've had fewer
problems in the long run. And it's relatively easy to go back and forth
between versions until I'm satisfied the new distro/myth version work
the way I want. I've been doing it this way for nearly 10 years.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/6/2017 6:39 PM, faginbagin wrote:
> Yep, I've still got a few old laptops that have been working quite well
> as frontends. But one isn't performing quite as well with mythtv 0.28
> and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu 12.04. So,
> I'm trying to understand why, and whether there's anything I can do to
> get it to perform running 0.28 as well as it does running 0.27. The
> laptop and the master backend have multiple boot partitions, so that's
> how I switch back and forth between 0.27 and 0.28
>
> I see slight but noticeable stuttering during panning scenes when I
> playback standard definition H.264 video on 0.28 but not when I play
> back the same video on 0.27. It's not CPU bound, the CPU hovers around
> 30% to 35% on both versions and might be using a tad less CPU on 0.28 as
> it does on 0.27.
>
> The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz CPU
> and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller. The
> display is 1280x800 resolution. It's configured to use the Slim playback
> profile on both 0.27 and 0.28, as defined in the database migrated from
> 0.27 to 0.28.
>
> I have compared mythfrontend logs using -v general,playback at the
> default info level. I can see no meaningful difference in the log
> output. I've hesitated to try the debug level, for fear that might push
> the CPU and/or disk to work too hard, although maybe that should be my
> next step?
>
> I have compared Xorg.0.log on both OSs, and only see slight differences
> like version numbers, and a handful of different messages that I suspect
> are due to logging changes in source and not meaningful.
>
> FWIW, the laptop can play 720p and 1080i MPEG2 transport streams
> smoothly in both 0.27 and 0.28. But it cannot play high definition H.264
> content on either, where it's definitely CPU bound. I've also got a
> couple of circa 2004 thinkpads with Pentium M CPUs and Radeon GPUs that
> CAN handle the SD H.264 in both 0.27 and 0.28 environments. It's just
> this Dell that's keeping me from cutting over to 0.28.
>
> Has anyone else noticed a degradation in performance on older hardware
> after upgrading?
>
> Any suggestions on how to identify the cause, e.g. OS module, X driver
> or mythtv?

This is my follow up to everyone who offered suggestions on getting my
old laptop to function on 0.28/16.04 at least as well as it did on
0.27/12.04. First a summary, then the gory details.

Summary:

I could not find a configuration that would allow 0.28 mythfrontend to
work as well as 0.27 mythfrontend playing standard definition h264
video. I think there's strong evidence that the problem is due to
something that changed in the mythfrontend or libmyth* code, not in the
OS, Xorg, or ffmpeg code that mythtv syncs with.

I found that mythtv 0.27 on mythbuntu 14.04 works as well as it did on
12.04. So, in order to get security updates for a couple more years, I
am upgrading all my machines running 12.04 to 14.04. Maybe this laptop
will give up the ghost before I get new hardware that really needs a
newer OS, Xorg or version of mythtv. Or I may set up a cross compile
environment on another machine so I can do a git bisect and identify an
offending commit. The laptop is too slow and doesn't have enough disk
space to do that.

Details:

Mike Perkins suggestions:
* Check wiki articles:
- https://www.mythtv.org/wiki/User_Manual:JudderFree
(Seconded by Anthony Giggens)
Not sure this article can help since I'm using the laptop's built in
display. xrandr reports:
Screen 0: minimum 320 x 200, current 1280 x 800, maximum 4096 x 4096
LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y axis)
331mm x 207mm
1280x800 60.0*+
1024x768 60.0
800x600 60.3 56.2
640x480 59.9
VGA1 disconnected (normal left inverted right x axis y axis)
TV1 disconnected (normal left inverted right x axis y axis)
As you can see, not much variation in refresh rates.
Gave it a try after RTC timer didn't help. Found that aspect ratios are
messed up and all video is pillar boxed. As you can see from the above
xrandr output, the display's native resolution is 1280x800, with an
aspect ratio of 16x10, but the alternate supported resolutions are all
4x3. I tried tinkering with aspect ratios during playback but could not
find anything sane, or any way to use the full width of the display.

- https://www.mythtv.org/wiki/Frame_display_timing
The laptop was using usleep in both 0.27 and 0.28. Getting RTC to work
sounded promising. I was really hoping this would do it, but it had no
effect. Tried both 1024 and 2048 for max_user_freq. It's hard to see
that going higher would help.

* Cut mythtv out, compare playback with vlc on 12.04 vs 16.04
If RTC doesn't help, this might provide more diagnostic info.
Played the troublesome SD h264 mp4 file on vlc. Looks fine on 16.04 with
vlc 2.2.2 and CPU is comparable to mythfrontend (see below). That's
using XVideo/xcb_xv video output, which I believe is comparable to
mythfrontend's Slim profile. Also tried OpenGL GLX/xcb_glx video output,
and found the CPU usage was about double the usage with XVideo output.
Also looks fine on 14.04 with vlc 2.1.6 (I had replaced 12.04 by this
time). Similar results WRT CPU usage, maybe 3-5 points lower. This seems
to suggest the problem is changes from 0.27 to 0.28 in mythfrontend.
Also suggests a possible workaround by configuring mythfrontend to use
vlc to playback h264 content.

* Try a "complex" transcode on the local test file using ffmpeg on
both 12.04 and 16.04 to see if that shows a significant difference or
not (something to make the laptop sweat / work hard so small differences
might be more readily noticed).
I think the idea is to compare how fast the laptop can decode the video
in 12.04 vs 16.04. Using mythffmpeg in both environments might provide
some insight into changes from 0.27 to 0.28 in the slim playback
profile's performance, since both mythffmpeg and mythfrontend use the
same code. Between this and comparing playback with vlc, it could
identify whether the problem is in mythtv or the O/S and/or Xorg
drivers. I decided to use mythffplay, since the problem is one of
decoding and display, not transcoding.
0.27/14.04, based on ffplay/ffmpeg 1.2.7. Works well, CPU is comparable
to mythfrontend with Slim profile.
0.28/16.04, based on ffplay/ffmpeg 3.0. Works well, CPU is comparable to
mythfrontend with Slim profile.
I think this is even stronger evidence than the vlc test that the
problem is not in the OS, Xorg, drivers, or in the port of ffmpeg to
mythtv, and narrows it down to the mythfrontend or libmyth* code that
supports mythfrontend.

My idea:
Try mythbuntu 14.04. It won't get me to mythtv 0.28, but it will give me
a couple more years of long term support and security updates from
Ubuntu. Seems to work as well as 12.04 and eliminates 2 years of OS and
Xorg changes as possible culprits. Only drawback is a slight increase in
memory usage, see stats for frames decoded/free suggestion.

Peter Bennett suggestions:
- Try an OpenGL playback profile. This is easy to test.
On 12.04 tried glxgears, it reported an average around 15fps, well below
the display's 60Hz refresh rate.
On 16.04 tried glxgears, it reported an average around 48fps, much
closer to the display's 60Hz refresh rate.
On 0.28/16.04 using "OpenGL Slim" playback profile pushes CPU usage up
about 15 percentage points. That's OK for the troublesome SD h264 video,
which plays more smoothly at around 50%. But HD mpeg2 content that plays
OK with the Slim profile, using 80-90% CPU, is now CPU bound and
stutters badly, much worse than the slight stuttering it fixes for SD
h264 video. That's true for both 720p and 1080i with the default One
Field deinterlacer as well as deinterlacing set to None. So using an
OpenGL profile fixes an annoying problem with one type of content but
creates more serious problems for other content.

- Could be https://code.mythtv.org/trac/ticket/12907
This ticket talks about problems playing 60fps video. It doesn't say
what encoding or resolution. The laptop can play 720p mpeg2 60fps video
running 0.28/16.04. My problem is with h264 encoding, standard
definition resolution, with an average frame rate less than 25fps.

Stuart Auchterlonie suggestion:
Monitor playback OSD frames decoded/free figures, should stay as high as
possible. I had used this to monitor CPU usage, but not frames decoded/free.
0.27/12.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
to 43% during panning.
top stats mythfrontend mem 14.8% Xorg 2.4%
0.27/14.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
to 43% during panning.
top stats mythfrontend mem 15.4% Xorg 2.6%
0.28/16.04 slim - consistently 28/1, CPU similar to 0.27/12.04.
top stats mythfrontend mem 23.5% Xorg 3.3%
0.28/16.04 opengl - consistently 28/1, CPU increased to around 50%
top stats mythfrontend mem 23.2% Xorg 2.0%

Brian Murrel suggestion:
Replace mythfrontend with Kodi.
I think this would involve a steep learning curve, not just for me, but
for my family. I would consider this a last choice.

Again, many thanks for everyone's suggestions. I welcome any other
ideas, thoughts, etc.
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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/16/2017 2:52 PM, faginbagin wrote:
> On 6/6/2017 6:39 PM, faginbagin wrote:
>> Yep, I've still got a few old laptops that have been working quite
>> well as frontends. But one isn't performing quite as well with mythtv
>> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
>> 12.04. So, I'm trying to understand why, and whether there's anything
>> I can do to get it to perform running 0.28 as well as it does running
>> 0.27. The laptop and the master backend have multiple boot
>> partitions, so that's how I switch back and forth between 0.27 and 0.28
>>
>> I see slight but noticeable stuttering during panning scenes when I
>> playback standard definition H.264 video on 0.28 but not when I play
>> back the same video on 0.27. It's not CPU bound, the CPU hovers
>> around 30% to 35% on both versions and might be using a tad less CPU
>> on 0.28 as it does on 0.27.
>>
>> The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz
>> CPU and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller.
>> The display is 1280x800 resolution. It's configured to use the Slim
>> playback profile on both 0.27 and 0.28, as defined in the database
>> migrated from 0.27 to 0.28.
>>
>> I have compared mythfrontend logs using -v general,playback at the
>> default info level. I can see no meaningful difference in the log
>> output. I've hesitated to try the debug level, for fear that might
>> push the CPU and/or disk to work too hard, although maybe that should
>> be my next step?
>>
>> I have compared Xorg.0.log on both OSs, and only see slight
>> differences like version numbers, and a handful of different messages
>> that I suspect are due to logging changes in source and not meaningful.
>>
>> FWIW, the laptop can play 720p and 1080i MPEG2 transport streams
>> smoothly in both 0.27 and 0.28. But it cannot play high definition
>> H.264 content on either, where it's definitely CPU bound. I've also
>> got a couple of circa 2004 thinkpads with Pentium M CPUs and Radeon
>> GPUs that CAN handle the SD H.264 in both 0.27 and 0.28 environments.
>> It's just this Dell that's keeping me from cutting over to 0.28.
>>
>> Has anyone else noticed a degradation in performance on older
>> hardware after upgrading?
>>
>> Any suggestions on how to identify the cause, e.g. OS module, X
>> driver or mythtv?
>
> This is my follow up to everyone who offered suggestions on getting my
> old laptop to function on 0.28/16.04 at least as well as it did on
> 0.27/12.04. First a summary, then the gory details.
>
> Summary:
>
> I could not find a configuration that would allow 0.28 mythfrontend to
> work as well as 0.27 mythfrontend playing standard definition h264
> video. I think there's strong evidence that the problem is due to
> something that changed in the mythfrontend or libmyth* code, not in
> the OS, Xorg, or ffmpeg code that mythtv syncs with.
>
> I found that mythtv 0.27 on mythbuntu 14.04 works as well as it did on
> 12.04. So, in order to get security updates for a couple more years, I
> am upgrading all my machines running 12.04 to 14.04. Maybe this laptop
> will give up the ghost before I get new hardware that really needs a
> newer OS, Xorg or version of mythtv. Or I may set up a cross compile
> environment on another machine so I can do a git bisect and identify
> an offending commit. The laptop is too slow and doesn't have enough
> disk space to do that.
>
> Details:
>
> Mike Perkins suggestions:
> * Check wiki articles:
> - https://www.mythtv.org/wiki/User_Manual:JudderFree
> (Seconded by Anthony Giggens)
> Not sure this article can help since I'm using the laptop's built in
> display. xrandr reports:
> Screen 0: minimum 320 x 200, current 1280 x 800, maximum 4096 x 4096
> LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y
> axis) 331mm x 207mm
> 1280x800 60.0*+
> 1024x768 60.0
> 800x600 60.3 56.2
> 640x480 59.9
> VGA1 disconnected (normal left inverted right x axis y axis)
> TV1 disconnected (normal left inverted right x axis y axis)
> As you can see, not much variation in refresh rates.
> Gave it a try after RTC timer didn't help. Found that aspect ratios
> are messed up and all video is pillar boxed. As you can see from the
> above xrandr output, the display's native resolution is 1280x800, with
> an aspect ratio of 16x10, but the alternate supported resolutions are
> all 4x3. I tried tinkering with aspect ratios during playback but
> could not find anything sane, or any way to use the full width of the
> display.
>
> - https://www.mythtv.org/wiki/Frame_display_timing
> The laptop was using usleep in both 0.27 and 0.28. Getting RTC to work
> sounded promising. I was really hoping this would do it, but it had no
> effect. Tried both 1024 and 2048 for max_user_freq. It's hard to see
> that going higher would help.
>
> * Cut mythtv out, compare playback with vlc on 12.04 vs 16.04
> If RTC doesn't help, this might provide more diagnostic info.
> Played the troublesome SD h264 mp4 file on vlc. Looks fine on 16.04
> with vlc 2.2.2 and CPU is comparable to mythfrontend (see below).
> That's using XVideo/xcb_xv video output, which I believe is comparable
> to mythfrontend's Slim profile. Also tried OpenGL GLX/xcb_glx video
> output, and found the CPU usage was about double the usage with XVideo
> output. Also looks fine on 14.04 with vlc 2.1.6 (I had replaced 12.04
> by this time). Similar results WRT CPU usage, maybe 3-5 points lower.
> This seems to suggest the problem is changes from 0.27 to 0.28 in
> mythfrontend. Also suggests a possible workaround by configuring
> mythfrontend to use vlc to playback h264 content.
>
> * Try a "complex" transcode on the local test file using ffmpeg on
> both 12.04 and 16.04 to see if that shows a significant difference or
> not (something to make the laptop sweat / work hard so small differences
> might be more readily noticed).
> I think the idea is to compare how fast the laptop can decode the
> video in 12.04 vs 16.04. Using mythffmpeg in both environments might
> provide some insight into changes from 0.27 to 0.28 in the slim
> playback profile's performance, since both mythffmpeg and mythfrontend
> use the same code. Between this and comparing playback with vlc, it
> could identify whether the problem is in mythtv or the O/S and/or Xorg
> drivers. I decided to use mythffplay, since the problem is one of
> decoding and display, not transcoding.
> 0.27/14.04, based on ffplay/ffmpeg 1.2.7. Works well, CPU is
> comparable to mythfrontend with Slim profile.
> 0.28/16.04, based on ffplay/ffmpeg 3.0. Works well, CPU is comparable
> to mythfrontend with Slim profile.
> I think this is even stronger evidence than the vlc test that the
> problem is not in the OS, Xorg, drivers, or in the port of ffmpeg to
> mythtv, and narrows it down to the mythfrontend or libmyth* code that
> supports mythfrontend.
>
> My idea:
> Try mythbuntu 14.04. It won't get me to mythtv 0.28, but it will give
> me a couple more years of long term support and security updates from
> Ubuntu. Seems to work as well as 12.04 and eliminates 2 years of OS
> and Xorg changes as possible culprits. Only drawback is a slight
> increase in memory usage, see stats for frames decoded/free suggestion.
>
> Peter Bennett suggestions:
> - Try an OpenGL playback profile. This is easy to test.
> On 12.04 tried glxgears, it reported an average around 15fps, well
> below the display's 60Hz refresh rate.
> On 16.04 tried glxgears, it reported an average around 48fps, much
> closer to the display's 60Hz refresh rate.
> On 0.28/16.04 using "OpenGL Slim" playback profile pushes CPU usage up
> about 15 percentage points. That's OK for the troublesome SD h264
> video, which plays more smoothly at around 50%. But HD mpeg2 content
> that plays OK with the Slim profile, using 80-90% CPU, is now CPU
> bound and stutters badly, much worse than the slight stuttering it
> fixes for SD h264 video. That's true for both 720p and 1080i with the
> default One Field deinterlacer as well as deinterlacing set to None.
> So using an OpenGL profile fixes an annoying problem with one type of
> content but creates more serious problems for other content.
>
> - Could be https://code.mythtv.org/trac/ticket/12907
> This ticket talks about problems playing 60fps video. It doesn't say
> what encoding or resolution. The laptop can play 720p mpeg2 60fps
> video running 0.28/16.04. My problem is with h264 encoding, standard
> definition resolution, with an average frame rate less than 25fps.
>
> Stuart Auchterlonie suggestion:
> Monitor playback OSD frames decoded/free figures, should stay as high
> as possible. I had used this to monitor CPU usage, but not frames
> decoded/free.
> 0.27/12.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
> to 43% during panning.
> top stats mythfrontend mem 14.8% Xorg 2.4%
> 0.27/14.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
> to 43% during panning.
> top stats mythfrontend mem 15.4% Xorg 2.6%
> 0.28/16.04 slim - consistently 28/1, CPU similar to 0.27/12.04.
> top stats mythfrontend mem 23.5% Xorg 3.3%
> 0.28/16.04 opengl - consistently 28/1, CPU increased to around 50%
> top stats mythfrontend mem 23.2% Xorg 2.0%
>
> Brian Murrel suggestion:
> Replace mythfrontend with Kodi.
> I think this would involve a steep learning curve, not just for me,
> but for my family. I would consider this a last choice.
>
> Again, many thanks for everyone's suggestions. I welcome any other
> ideas, thoughts, etc.
> _______________________________________________
> mythtv-users mailing list
> mythtv-users@mythtv.org
> http://lists.mythtv.org/mailman/listinfo/mythtv-users
> http://wiki.mythtv.org/Mailing_List_etiquette
> MythTV Forums: https://forum.mythtv.org
>
Did you try 0.28 on 14.04? That is an available supported option AFAIK.

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Re: 2005 laptop stutters after upgrade from 0.27 to 0.28 [ In reply to ]
On 6/16/2017 5:58 PM, Jay Foster wrote:
> On 6/16/2017 2:52 PM, faginbagin wrote:
>> On 6/6/2017 6:39 PM, faginbagin wrote:
>>> Yep, I've still got a few old laptops that have been working quite
>>> well as frontends. But one isn't performing quite as well with mythtv
>>> 0.28 and mythbuntu 16.04 as it is with mythtv 0.27 and mythbuntu
>>> 12.04. So, I'm trying to understand why, and whether there's anything
>>> I can do to get it to perform running 0.28 as well as it does running
>>> 0.27. The laptop and the master backend have multiple boot
>>> partitions, so that's how I switch back and forth between 0.27 and 0.28
>>>
>>> I see slight but noticeable stuttering during panning scenes when I
>>> playback standard definition H.264 video on 0.28 but not when I play
>>> back the same video on 0.27. It's not CPU bound, the CPU hovers
>>> around 30% to 35% on both versions and might be using a tad less CPU
>>> on 0.28 as it does on 0.27.
>>>
>>> The laptop is a Dell Inspiron B130 with an Intel Celeron M 1.5 GHz
>>> CPU and an Intel Mobile 915GM/GMS/910GML Express Graphics Controller.
>>> The display is 1280x800 resolution. It's configured to use the Slim
>>> playback profile on both 0.27 and 0.28, as defined in the database
>>> migrated from 0.27 to 0.28.
>>>
>>> I have compared mythfrontend logs using -v general,playback at the
>>> default info level. I can see no meaningful difference in the log
>>> output. I've hesitated to try the debug level, for fear that might
>>> push the CPU and/or disk to work too hard, although maybe that should
>>> be my next step?
>>>
>>> I have compared Xorg.0.log on both OSs, and only see slight
>>> differences like version numbers, and a handful of different messages
>>> that I suspect are due to logging changes in source and not meaningful.
>>>
>>> FWIW, the laptop can play 720p and 1080i MPEG2 transport streams
>>> smoothly in both 0.27 and 0.28. But it cannot play high definition
>>> H.264 content on either, where it's definitely CPU bound. I've also
>>> got a couple of circa 2004 thinkpads with Pentium M CPUs and Radeon
>>> GPUs that CAN handle the SD H.264 in both 0.27 and 0.28 environments.
>>> It's just this Dell that's keeping me from cutting over to 0.28.
>>>
>>> Has anyone else noticed a degradation in performance on older
>>> hardware after upgrading?
>>>
>>> Any suggestions on how to identify the cause, e.g. OS module, X
>>> driver or mythtv?
>>
>> This is my follow up to everyone who offered suggestions on getting my
>> old laptop to function on 0.28/16.04 at least as well as it did on
>> 0.27/12.04. First a summary, then the gory details.
>>
>> Summary:
>>
>> I could not find a configuration that would allow 0.28 mythfrontend to
>> work as well as 0.27 mythfrontend playing standard definition h264
>> video. I think there's strong evidence that the problem is due to
>> something that changed in the mythfrontend or libmyth* code, not in
>> the OS, Xorg, or ffmpeg code that mythtv syncs with.
>>
>> I found that mythtv 0.27 on mythbuntu 14.04 works as well as it did on
>> 12.04. So, in order to get security updates for a couple more years, I
>> am upgrading all my machines running 12.04 to 14.04. Maybe this laptop
>> will give up the ghost before I get new hardware that really needs a
>> newer OS, Xorg or version of mythtv. Or I may set up a cross compile
>> environment on another machine so I can do a git bisect and identify
>> an offending commit. The laptop is too slow and doesn't have enough
>> disk space to do that.
>>
>> Details:
>>
>> Mike Perkins suggestions:
>> * Check wiki articles:
>> - https://www.mythtv.org/wiki/User_Manual:JudderFree
>> (Seconded by Anthony Giggens)
>> Not sure this article can help since I'm using the laptop's built in
>> display. xrandr reports:
>> Screen 0: minimum 320 x 200, current 1280 x 800, maximum 4096 x 4096
>> LVDS1 connected 1280x800+0+0 (normal left inverted right x axis y
>> axis) 331mm x 207mm
>> 1280x800 60.0*+
>> 1024x768 60.0
>> 800x600 60.3 56.2
>> 640x480 59.9
>> VGA1 disconnected (normal left inverted right x axis y axis)
>> TV1 disconnected (normal left inverted right x axis y axis)
>> As you can see, not much variation in refresh rates.
>> Gave it a try after RTC timer didn't help. Found that aspect ratios
>> are messed up and all video is pillar boxed. As you can see from the
>> above xrandr output, the display's native resolution is 1280x800, with
>> an aspect ratio of 16x10, but the alternate supported resolutions are
>> all 4x3. I tried tinkering with aspect ratios during playback but
>> could not find anything sane, or any way to use the full width of the
>> display.
>>
>> - https://www.mythtv.org/wiki/Frame_display_timing
>> The laptop was using usleep in both 0.27 and 0.28. Getting RTC to work
>> sounded promising. I was really hoping this would do it, but it had no
>> effect. Tried both 1024 and 2048 for max_user_freq. It's hard to see
>> that going higher would help.
>>
>> * Cut mythtv out, compare playback with vlc on 12.04 vs 16.04
>> If RTC doesn't help, this might provide more diagnostic info.
>> Played the troublesome SD h264 mp4 file on vlc. Looks fine on 16.04
>> with vlc 2.2.2 and CPU is comparable to mythfrontend (see below).
>> That's using XVideo/xcb_xv video output, which I believe is comparable
>> to mythfrontend's Slim profile. Also tried OpenGL GLX/xcb_glx video
>> output, and found the CPU usage was about double the usage with XVideo
>> output. Also looks fine on 14.04 with vlc 2.1.6 (I had replaced 12.04
>> by this time). Similar results WRT CPU usage, maybe 3-5 points lower.
>> This seems to suggest the problem is changes from 0.27 to 0.28 in
>> mythfrontend. Also suggests a possible workaround by configuring
>> mythfrontend to use vlc to playback h264 content.
>>
>> * Try a "complex" transcode on the local test file using ffmpeg on
>> both 12.04 and 16.04 to see if that shows a significant difference or
>> not (something to make the laptop sweat / work hard so small differences
>> might be more readily noticed).
>> I think the idea is to compare how fast the laptop can decode the
>> video in 12.04 vs 16.04. Using mythffmpeg in both environments might
>> provide some insight into changes from 0.27 to 0.28 in the slim
>> playback profile's performance, since both mythffmpeg and mythfrontend
>> use the same code. Between this and comparing playback with vlc, it
>> could identify whether the problem is in mythtv or the O/S and/or Xorg
>> drivers. I decided to use mythffplay, since the problem is one of
>> decoding and display, not transcoding.
>> 0.27/14.04, based on ffplay/ffmpeg 1.2.7. Works well, CPU is
>> comparable to mythfrontend with Slim profile.
>> 0.28/16.04, based on ffplay/ffmpeg 3.0. Works well, CPU is comparable
>> to mythfrontend with Slim profile.
>> I think this is even stronger evidence than the vlc test that the
>> problem is not in the OS, Xorg, drivers, or in the port of ffmpeg to
>> mythtv, and narrows it down to the mythfrontend or libmyth* code that
>> supports mythfrontend.
>>
>> My idea:
>> Try mythbuntu 14.04. It won't get me to mythtv 0.28, but it will give
>> me a couple more years of long term support and security updates from
>> Ubuntu. Seems to work as well as 12.04 and eliminates 2 years of OS
>> and Xorg changes as possible culprits. Only drawback is a slight
>> increase in memory usage, see stats for frames decoded/free suggestion.
>>
>> Peter Bennett suggestions:
>> - Try an OpenGL playback profile. This is easy to test.
>> On 12.04 tried glxgears, it reported an average around 15fps, well
>> below the display's 60Hz refresh rate.
>> On 16.04 tried glxgears, it reported an average around 48fps, much
>> closer to the display's 60Hz refresh rate.
>> On 0.28/16.04 using "OpenGL Slim" playback profile pushes CPU usage up
>> about 15 percentage points. That's OK for the troublesome SD h264
>> video, which plays more smoothly at around 50%. But HD mpeg2 content
>> that plays OK with the Slim profile, using 80-90% CPU, is now CPU
>> bound and stutters badly, much worse than the slight stuttering it
>> fixes for SD h264 video. That's true for both 720p and 1080i with the
>> default One Field deinterlacer as well as deinterlacing set to None.
>> So using an OpenGL profile fixes an annoying problem with one type of
>> content but creates more serious problems for other content.
>>
>> - Could be https://code.mythtv.org/trac/ticket/12907
>> This ticket talks about problems playing 60fps video. It doesn't say
>> what encoding or resolution. The laptop can play 720p mpeg2 60fps
>> video running 0.28/16.04. My problem is with h264 encoding, standard
>> definition resolution, with an average frame rate less than 25fps.
>>
>> Stuart Auchterlonie suggestion:
>> Monitor playback OSD frames decoded/free figures, should stay as high
>> as possible. I had used this to monitor CPU usage, but not frames
>> decoded/free.
>> 0.27/12.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
>> to 43% during panning.
>> top stats mythfrontend mem 14.8% Xorg 2.4%
>> 0.27/14.04 slim - consistently 28/1, and CPU approx 30-40%, briefly up
>> to 43% during panning.
>> top stats mythfrontend mem 15.4% Xorg 2.6%
>> 0.28/16.04 slim - consistently 28/1, CPU similar to 0.27/12.04.
>> top stats mythfrontend mem 23.5% Xorg 3.3%
>> 0.28/16.04 opengl - consistently 28/1, CPU increased to around 50%
>> top stats mythfrontend mem 23.2% Xorg 2.0%
>>
>> Brian Murrel suggestion:
>> Replace mythfrontend with Kodi.
>> I think this would involve a steep learning curve, not just for me,
>> but for my family. I would consider this a last choice.
>>
>> Again, many thanks for everyone's suggestions. I welcome any other
>> ideas, thoughts, etc.
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>>
> Did you try 0.28 on 14.04? That is an available supported option AFAIK.

Hi Jay,

Thanks for the suggestion, I'll keep it in mind, although I'm not very
hopeful it will help this laptop. I think the mythffplay test strongly
suggests the problem lies in mythfrontend/libmyth* code.
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