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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi everyone<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Having some issues with my latest incarnation of MythTV.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It’s mythbuntu based from 12.04 and updated to the latest everything. Mythbackend reports as “mythbackend version: fixes/0.25 [v0.25.3-48-g3a1eff8] <a href="http://www.mythtv.org">www.mythtv.org</a>”<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>CPU is an i3-2100 on an ASRock B75-PRO3-M motherboard, 3GB RAM, 3TB main drive and a couple of other smaller ones. Playback is VDPAU which works OK.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>hdparm –t reports speeds of 60-70MByte/sec no problem on all drives and only 4-5MB/sec when recording as expected. There seems to be no actual issue with recordings. There are no corruptions or dropouts ever that I notice.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Tuners are two dual tuner “USB Lifeview TV Walker Twin” devices for a total of 4 DVB-T tuners. I have 4 virtual tuners on each although rarely do they ever get exercised to the full extent. Helpful for overlapping recordings though.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>My problem is that when a recording is running I’m seeing quite high CPU usage from mythbackend. A HD show (1440x1080) will take 60-80% CPU per recording. When a couple of recordings are going I see something like the top output below (2 x HD and 1 x SD recordings) with a load average to match. DVB-T recordings really shouldn’t need much/any CPU. Load average occasionally even gets up to 8-10 or more.<o:p></o:p></p><p class=MsoNormal><span style='font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>top - 20:46:06 up 1 day, 8:55, 3 users, load average: 5.29, 5.88, 6.49<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>Tasks: 211 total, 2 running, 208 sleeping, 1 stopped, 0 zombie<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>Cpu(s): 20.4%us, 29.0%sy, 0.1%ni, 45.4%id, 5.1%wa, 0.0%hi, 0.0%si, 0.0%st<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>Mem: 3023632k total, 2953156k used, 70476k free, 12280k buffers<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'>Swap: 9765884k total, 447804k used, 9318080k free, 1418564k cached<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 4197 mythtv 20 0 2927m 121m 6040 S 202 4.1 1028:10 mythbackend<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 8672 mythtvus 20 0 3007m 247m 30m S 4 8.4 57:35.85 mythfrontend.re<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 1627 root 20 0 188m 51m 23m S 1 1.7 4:59.26 Xorg<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 595 root 20 0 0 0 0 S 0 0.0 0:20.11 jbd2/sda3-8<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 1419 mysql 20 0 2434m 152m 4212 S 0 5.2 75:42.51 mysqld<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 1462 root 20 0 32908 604 504 S 0 0.0 3:47.02 lircd<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New"'> 2705 nobody 20 0 16972 704 636 S 0 0.0 5:21.88 LCDd<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This in turn really slows the whole system down which is a problem since it’s an all in one machine. Often it will drop out with “irrecoverable recorder error” back to the recordings screen. The recording doesn’t seem at affected though and I just start it again and it works. 1000 minutes over 32 hours is a fair bit of CPU time just for recordings. Doing something like moving a file from one disk to another seems to make it even worse (but I get a get 60-70 MByte/sec transfer speeds)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I only have a 1 instance of mythcommflag running at once but even killing that one makes no difference. It’s a separate process anyway.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This didn’t happen previously (was using Mythdora 12.25) on the same tuners (same CPU but different motherboard).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Otherwise it works quite well. Is this CPU usage likely to be MythTV building the recordedseek table for the recordings that are running? That’s about all I can think of. Is it normal now? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sorry about the length - tried to include as much detail as I can. I don’t see much that is helpful in any logs.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Any ideas? Is this just “normal”? With a few recordings it’s a bit painful to use particularly when it keeps dropping out of playback. The machine is not a powerhouse but should be easily capable of what I’m doing.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks<o:p></o:p></p><p class=MsoNormal>Christian<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>