Re: [mythtv-users] Software RAID problems - the unspokenmythtvproblem?
Yeechang and everyone else who has been so helpful, I must admit I am quite fascinated by the Raid and NAS discussions, but given that I ran into the same problem of being unable to record two programs at once on my software RAID, I am grateful for Yeechang to try and help steer things back towards my original question. Quick summary: When on a software RAID two programs cannot be recorded when they start at the same time. The second program (always starting 0.3 seconds after the first) does not record and ends up as a 0 byte file. This only happens when the video/recordings is on my software raid. (this is key. i can switch over to another non raided hard drive and have no problems doing the exact same thing!) I an running linux kernel 2.6, 512mb, celeron (fairly fast but a celeron nonetheless). I am using 2 drives in Raid 1 (had same trouble with Raid 5 though) and am using a Sata IDE extender to add sata ports (but this is probably irrelevant as I had the problem before I installed this.) Some people have suggested that the celeron might be the problem, but is this possible? No errors on dmesg, and no errors on mythbackend.log until I try and see the recorded programs on mythweb. Memory is full (as always... is this normal?) but the Swap is empty (only 1%). Top doesnt show Mythbackend anywhere near the top. Here is what my log shows: 2006-01-12 20:59:02.889 Started recording けものみち on channel: 4 on cardid: 1, sourceid 1 2006-01-12 20:59:03.029 New DB connection, total: 4 2006-01-12 20:59:03.033 New DB connection, total: 5 2006-01-12 20:59:03.043 scheduler: Last message repeated 7 times 2006-01-12 20:59:03.060 scheduler: Schedule Change 2006-01-12 20:59:03.078 Started recording 白夜行 on channel: 6 on cardid: 2, s ourceid 1 QMetaObjectCleanUp::setMetaObject: Double use of QMetaObjectCleanUp! 2006-01-12 20:59:03.875 Changing from None to RecordingOnly 2006-01-12 20:59:03.877 Changing from None to RecordingOnly 2006-01-12 22:09:00.037 Finished recording けものみち on channel: 4 the 2nd program's video file is 0 byte file size. (and the 2nd program always does not seem to work.) Suggestions so far: celeron cant handle it (cache issues) --- a possibility? memory -- not sure myself drive spinning - maybe the drives are spinning down. this is also possible but as they are sata i cant seem to change them with hdparm. So much frustration!! arg, any ideas? raid caching or the likes? (-- i made that up!) thank you kindly david ps. yeechan - i am quite excited to hear how your ReadyNAS handles! ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Software RAID problems - the unspokenmythtvproblem?
On Thursday 12 January 2006 09:01, David Bennett wrote: Yeechang and everyone else who has been so helpful, I must admit I am quite fascinated by the Raid and NAS discussions, but given that I ran into the same problem of being unable to record two programs at once on my software RAID, I am grateful for Yeechang to try and help steer things back towards my original question. Quick summary: When on a software RAID two programs cannot be recorded when they start at the same time. The second program (always starting 0.3 seconds after the first) does not record and ends up as a 0 byte file. This only happens when the video/recordings is on my software raid. (this is key. i can switch over to another non raided hard drive and have no problems doing the exact same thing!) I an running linux kernel 2.6, 512mb, celeron (fairly fast but a celeron nonetheless). I am using 2 drives in Raid 1 (had same trouble with Raid 5 though) and am using a Sata IDE extender to add sata ports (but this is probably irrelevant as I had the problem before I installed this.) Some people have suggested that the celeron might be the problem, but is this possible? No errors on dmesg, and no errors on mythbackend.log until I try and see the recorded programs on mythweb. Memory is full (as always... is this normal?) but the Swap is empty (only 1%). Top doesnt show Mythbackend anywhere near the top. Here is what my log shows: 2006-01-12 20:59:02.889 Started recording けものみち on channel: 4 on cardid: 1, sourceid 1 2006-01-12 20:59:03.029 New DB connection, total: 4 2006-01-12 20:59:03.033 New DB connection, total: 5 2006-01-12 20:59:03.043 scheduler: Last message repeated 7 times 2006-01-12 20:59:03.060 scheduler: Schedule Change 2006-01-12 20:59:03.078 Started recording 白夜行 on channel: 6 on cardid: 2, s ourceid 1 QMetaObjectCleanUp::setMetaObject: Double use of QMetaObjectCleanUp! 2006-01-12 20:59:03.875 Changing from None to RecordingOnly 2006-01-12 20:59:03.877 Changing from None to RecordingOnly 2006-01-12 22:09:00.037 Finished recording けものみち on channel: 4 the 2nd program's video file is 0 byte file size. (and the 2nd program always does not seem to work.) Suggestions so far: celeron cant handle it (cache issues) --- a possibility? memory -- not sure myself drive spinning - maybe the drives are spinning down. this is also possible but as they are sata i cant seem to change them with hdparm. So much frustration!! arg, any ideas? raid caching or the likes? (-- i made that up!) thank you kindly david ps. yeechan - i am quite excited to hear how your ReadyNAS handles! As a test I just set two HD shows to record, both began at the same time and both are being written to my RAID5 array. this is with MythTV SVN though. -- Steve ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Software RAID problems - the unspokenmythtvproblem?
for what its worth, I am using 2 firewire encoders with a local 7 drive raid5. I am using latest ATrpms on FC3. kernel 2.6.12 smp. I have had no problems with simultaneous HD recordings (even starting at the same time), and the performance seems to be better than my old 2 drive LVM configuration. My system: P4 3.2 (with HT) 1 G RAM 2 onboard SATA ports 3 ATA/133 cards with 2 channels each -- one drive per channel 6 x wd2500 (woot's 250 G drive) 2 x Hitachi SATA 250 G 2 x on-board Firewire capture 6 ATA and 1 SATA make the raid5, and the other SATA is root. /dev/md0 is formatted XFS for 1.45 TB The only RAID problem I had was one of the WD drives dropped off, not bad, just needed a reset. The system hung twice during the subsequent rebuilds. Added the drive back, and its all happy now. No recording problems at all. I actually stopped getting glitches in my HD records (part due to better RAID performance, part due to no longer running commercial detection) ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Software RAID problems - the unspokenmythtvproblem?
...a proper server setup should have more than enough bandwidth for even the largest software RAID 5 setups. Note I wrote proper server setup. By this I mean a high-quality motherboard with 64-bit PCI-X or PCI Express slots and multiple buses serving the expansion slots. My RAID 5 array is on a Supermicro X5DAL-G motherboard with two 64-bit 133MHz PCI-X slots and three buses (one for each of the PCI-X slots and a third for the regular PCI slots; there is a reason why 3Ware cards support 64-bit PCI-X). By contrast, simply stuffing controller cards and drives into the old unused consumer-grade system you have sitting in the closet is not ideal. At best performance will be acceptable; at worst your poor motherboard--never designed for the amount of stress you're applying to its (likely single) bus by sending so much data over it at once--will freak out, causing parity errors. I think the point here is that we know spending a months salary or more will get us a superior system, which is obviously what you've done, unless you have more creative ways of obtaining your hardware, but myself and others believe we are just building a fancy VCR, and we actually enjoy pushing the envelope of our older unused hardware, and we simply enjoy the challenge. It's fun to find out how far some old motherboard can go and what we can do for cheap. I'm much more impressed by someone who can get MythTV up and running on some old junk than by those that do it the proper way. winmail.dat___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
