[mythtv-users] "VIDIOCSYNC: Input/output error" and dumps core--- Cured: buy better memory.

Gregory J. McGee gjmcgee at cableone.net
Mon Mar 29 03:28:47 EST 2004

Short: Buy GOOD fast memory, and crank your FSB. Mythtv likes it.


I have gradually come to the conclusion that almost all Myth issues are
really driver/MB or some other type of hardware glitch...

(Oh, Mandrake cooker, current, using Thacs mdk9.2 mythtv rpms)

Symptoms were:
Mythbackend dumps core, usually ~6-20 min into a recording, also "ran
out of free AUDIO buffers :-(" and "VIDIOCSYNC: Input/output error" msgs
in mythbackend log. Usually I would see a few of those msgs
intermittently and then it would core dump.

I had an interesting night jacking with myth, since making some hardware
changes ~last week (more memory) started having mythbackend drop core
while recording, and ended up putting the rocking single 256M cas2
pc3200 stick back in.

(...after trying other myth builds, (including CVS) and reloading a
system image from when it was working flawlessly for a week--kept having
basically the same issue (intermittently), but the symptoms varied

Now again all back to original setup save for the bttv update and a
k7/low latency kernel build (perhaps I should change one thing at a time
11x190 5222 memory settings (2100+ XP, rev1 NF2 FIC AU11 or I'd be at
210 FSB)

The offending stuff was Mushkin pc2700, good quality but not fancy
stuff, even cratered at 133fsb/default/slower timings, system may have
just been starved for memory bandwith. At least myth didn't like it.
(It passes memory tests using suse demo disc even cranked :/

Mythtv recording Farscape now seems to be trucking along just fine,
720x480 mpeg4 (2800bps/HQ/4MV) on the fly, just using a little swap
since I'm running KDE. (and running evolution, and mozilla, and a few
shells,bittorrenting an iso image, and compiling 2.4.3-7 niced... 
And mythfrontend is playing what's being recorded in an iconified
window... Ack.

Torture test anyone? 
(If it doesn't /die doing this, I think it's fixed, gets a second
Kingston Hyper-X 3200 cas2 memory stick tomorrow)

(it recorded fine, BTW, and I'm recording random shows on random
channels all night to test it and the bttv update)
Gregory J. McGee <gjmcgee at cableone.net>

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