id,summary,reporter,owner,description,type,status,priority,milestone,component,version,severity,resolution,keywords,cc,mlocked 9794,Remote frontend temporarily pausing during playback of recorded or live tv,lists@…,,"I'm having a problem with playback of recorded material on a remote frontend in 0.24-fixes. Playback hangs momentarily during start/stop of recordings on the backend, during a reschedule on the backend, or during expiration of recordings from the backend. I've gone through my configuration to try and debug this problem and consider there must be some kind of problem with locking in the backend code which I cannot work around. I noticed that there was a peak in hard drive access on the backend during a pause and a bit of digging showed that mysql was creating a temporary table on disk, so I put the temp dir for mysql on a ramdisk and this shortened the length of the pauses. It seems to me that the backend is locking on the result of a database query which starves the frontend of data. I tried tuning mysql using mysqltuner.pl and things got much better, but the pauses (which are much shorter now) still occur. I've also tried mounting the recording directory via nfs (using nfs-kernel-server) but this hasn't improved the situation. I can play back local or network mounted HD files (big buck bunny) on the frontend with other software using vdpau and have no issues. There were no issues with this hardware for versions of mythtv prior to upgrading to 0.24-fixes. The load on the backend is low with little other software running. Stressing up this machine via dd or other operations does not cause a pause on the frontend. Reception gives a 100% lock when viewing live tv in the frontend, and recordings play back fine on other systems. My config: - 2 x HD Homerun DVB-T (multirec, 4 tuners per physical = 16 in total) - As I'm in Australia, DVB-T broadcasts MPEG2 - I transcode to H264 via a custom transcoding job with a locally built ffmpeg. - Gigabit network Whitebox backend (Ubuntu 10.04) with: - Xeon CPU 3040 @ 1.86GHz - 4G ram, 92 kb of swap used after weeks of running - xfs recording filesystem on hardware raid 1 - ext3 filesystem on a separate hardware raid 1 for the database - Hardware raid can easily sustain 50 MB/s sustained read and writes with other activity happening on the machine. ION frontend (Mythbuntu 11.04) with: - nothing fancy, just a 250G sata drive - vga output to component feed in to old crt widescreen hdtv (720p) via a converter box (audio-authority unit) I've tried pretty much all the debugging I can, but can't seem to solve the problem. If there is any other information I can provide, please let me know. Backend Version (frontend running the same version from the mythbuntu daily build repository): Please attach all output as a file in bug reports. MythTV Version : v0.24-287-g8dd67eb MythTV Branch : fixes/0.24 Network Protocol : 63 Library API : 0.24.20110505-1 QT Version : 4.6.2 Options compiled in: linux debug using_alsa using_oss using_pulse using_pulseoutput using_backend using_bindings_perl using_bindings_python using_directfb using_dvb using_firewire using_frontend using_hdhomerun using_hdpvr using_iptv using_ivtv using_joystick_menu using_lirc using_mheg using_opengl_video using_opengl_vsync using_qtdbus using_qtwebkit using_v4l using_v4l2 using_x11 using_xrandr using_xv using_bindings_perl using_bindings_python using_mythtranscode using_opengl using_vdpau using_ffmpeg_threads using_live using_mheg Note: This is my first bug report, so I'm not sure I've done this all correctly. I have searched the list of tickets already and didn't find any that were duplicates of this one. ",Bug Report - General,closed,blocker,,MythTV - General,0.24-fixes,medium,Fixed,,,0