[mythtv-users] Software RAID problems - the unspokenmythtvproblem?

[David Bennett]

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 "$B$1$b$N$_$A(B" on channel: 4 on cardid:
1, sourceid 1
2006-01-12 20:59:03.029 New DB connection, total: 4
2006-01-12 20:59:03.033 New DB connection, total: 5
2006-01-12 20:59:03.043 scheduler: Last message repeated 7 times
2006-01-12 20:59:03.060 scheduler: Schedule Change
2006-01-12 20:59:03.078 Started recording "$BGrLk9T(B" 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 $B$1$b$N$_$A(B 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!