Opened 6 years ago

Last modified 6 years ago

#10998 new Bug Report - General

LiveTV channel change failing with Ceton and pc3000 cards

Reported by: Jeff Markley <jeff@…> Owned by:
Priority: minor Milestone: unknown
Component: MythTV - Video Playback Version: Unspecified
Severity: medium Keywords:
Cc: Ticket locked: no

Description

While researching various bugs with LiveTV both "Open" and "Closed" ticket #9201 most accurately matches an issue which my myth ecosystem experiences. That ticket is now closed.

"Changing channels on livetv often fails with "Video frame buffering failed too many times." or "Error opening jump program file buffer". Sometimes the error message takes quite some time to pop up. While waiting, FE is unresponsive with dark screen. Happens also while watching livetv, but not so often as when changing channel."

I first noticed the issue when adding a Ceton card and Ron Fraizer's patch to 0.24.1. It has continued to been an issue for me in every release since.

With all the commotion now around LiveTV I thought the following information would help.

Background:

System(s):

Combined BE/FE system: My primary system is an Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz stepping 0b running Debian Squeeze 2.6.32-5-amd64 #1 SMP Fri Sep 9 20:23:16 UTC 2011 x86_64 GNU/Linux with X.Org X Server 1.7.7 Release Date: 2010-05-04 X Protocol Version 11, Revision 0 Build Operating System: Linux 2.6.37-trunk-amd64 x86_64 Debian Current Operating System: Linux mythhd 2.6.32-5-amd64 #1 SMP Fri Sep 9 20:23:16 UTC 2011 x86_64 and an NVIDIA Corporation NV34 8500 GT?. The system has one Ceton card with CableCard?? (Xfinity) and two pc3000 DVB off-air cards.

Current Myth configuration is as follows:

mythhd:~# mythbackend --version Please attach all output as a file in bug reports. MythTV Version : v0.26-beta-9-g8c551e6 MythTV Branch : master Network Protocol : 75 Library API : 0.26.20120807-1 QT Version : 4.6.3 Options compiled in:

linux profile use_hidesyms using_alsa using_jack using_oss using_backend using_bindings_perl using_bindings_python using_bindings_php using_dvb using_frontend using_hdhomerun using_ceton using_iptv using_ivtv using_joystick_menu using_libcrypto using_libdns_sd using_libxml2 using_libudf using_lirc using_mheg using_opengl_video using_qtwebkit using_qtscript using_qtdbus using_v4l2 using_v4l1 using_x11 using_xrandr using_xv using_bindings_perl using_bindings_python using_bindings_php using_mythtranscode using_opengl using_ffmpeg_threads using_live using_mheg using_libxml2 using_libudf

mythhd:~# mythfrontend --version Please attach all output as a file in bug reports. MythTV Version : v0.26-beta-9-g8c551e6 MythTV Branch : master Network Protocol : 75 Library API : 0.26.20120807-1 QT Version : 4.6.3 Options compiled in:

linux profile use_hidesyms using_alsa using_jack using_oss using_backend using_bindings_perl using_bindings_python using_bindings_php using_dvb using_frontend using_hdhomerun using_ceton using_iptv using_ivtv using_joystick_menu using_libcrypto using_libdns_sd using_libxml2 using_libudf using_lirc using_mheg using_opengl_video using_qtwebkit using_qtscript using_qtdbus using_v4l2 using_v4l1 using_x11 using_xrandr using_xv using_bindings_perl using_bindings_python using_bindings_php using_mythtranscode using_opengl using_ffmpeg_threads using_live using_mheg using_libxml2 using_libudf

Other Frontends: I have four other frontends (2 Intel/Nvidia?? and 2 MacBook?? Pros) All frontends exhibit the same issue.

Storage: Initially storage was a group of 4 internal SATA drives in an LVM RAID 0 configuration. While fighting the "Program Boundary Pauseing" issue I moved storage to an NFS share located on a NETGEAR ReadyNas?? Pro. This effort reduced the pausing greatly (from ~10 sec to ~2) but had no effect on the LiveTV channel change issue. Another point to make here is a test performed to make sure my network was not the issue where I started 4 Ceton Xfinity HD recordings and 4 recorded program playbacks on my FE's. This stress test proved my gigE network was up to the test as now playback issues were encountered.

Findings:

Selecting "Watch TV" from the UI always results in a successful tune of a Ceton tuner to the last successfully tuned channel.

Changing channels in LiveTV on the Ceton card results in the "Error opening jump program file buffer" 90+% of the time. To be clear this situation is tuning to another Ceton CableCard?? Xfinity channel from a Ceton CableCard?? Xfinity channel. I am able to switch inputs to other Ceton tuners which always results in a successful tune to the last tuned channel. Using the program guide to change channels then results in the "Error opening jump program file buffer" message. The only work around is to use the program guide to select a channel on one of my pc3000 cards which completed successfully and then use the guide to select a Ceton channel. This works 90+% of the time. That said it seems the extra delay in switching tuner cards results in successful channel changes. Channel changes involving the same tuner are where I see my issue.

I am available for testing/debugging.

Attachments (2)

mythbackend.20120810142930.2808.log (88.9 KB) - added by Jeff Markley <jeff@…> 6 years ago.
BE log
mythfrontend.log (225.7 KB) - added by Jeff Markley <jeff@…> 6 years ago.
FE log

Download all attachments as: .zip

Change History (3)

Changed 6 years ago by Jeff Markley <jeff@…>

BE log

Changed 6 years ago by Jeff Markley <jeff@…>

Attachment: mythfrontend.log added

FE log

comment:1 Changed 6 years ago by Jeff Markley <jeff@…>

Moving the live tv buffer to a local disk partition on the combined FE/BE has resulted in better LiveTV performance however the "Error opening jump program file buffer" still occurs when changing channels about 1 in 8 tries. The frontend also segfaults and dies. Trying to get a backtrace now.

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