[mythtv-users] zilog-rx-i2c high cpu usage, lirc_zilog errors

[Jarod Wilson]

On Jun 5, 2011, at 10:17 AM, Jarod Wilson wrote:

> On Jun 4, 2011, at 1:55 PM, Chris Payne wrote:
> 
>>> Things are working well, one last detail is that I am seeing high cpu usage from this related process:
>>> 
>>> PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>>> 1645 root      20   0     0    0    0 R 99.2  0.0   1238:40 zilog-rx-i2c-1
>>> 
>>> And some messages whenever the channel change script runs:
>>> 
>>> Jun  3 19:00:02 hptv lircd-0.9.0[1649]: accepted new client on /var/run/lirc/lircd1
>>> Jun  3 19:00:02 hptv lircd-0.9.0[1649]: removed client
>>> Jun  3 19:00:02 hptv kernel: [28087.235192] lirc_zilog: i2c_master_recv failed with -5 -- keeping last read buffer
>>> Jun  3 19:00:02 hptv kernel: [28087.248190] lirc_zilog: i2c_master_recv failed with -5 -- keeping last read buffer
>>> Jun  3 19:00:03 hptv lircd-0.9.0[1649]: accepted new client on /var/run/lirc/lircd1
>>> Jun  3 19:00:03 hptv lircd-0.9.0[1649]: removed client
>>> Jun  3 19:00:03 hptv kernel: [28088.148469] lirc_zilog: i2c_master_recv failed with -5 -- keeping last read buffer
>>> Jun  3 19:00:03 hptv kernel: [28088.161470] lirc_zilog: i2c_master_recv failed with -5 -- keeping last read buffer
>>> 
>>> Which I am still investigating.
>> 
>> I've seen similar reported recently on the #linuxtv irc channel. Do you have
>> just one hdpvr, or are there two? Guess I need to do some investigation, but
>> my hdpvr recently got promoted from devel toy to being in use in my production
>> mythtv setup, which complicates things. Maybe I should see about just getting
>> another one...
>> 
>> 
>> I have just the one HDPVR, and even though it is just a loaner for now, it has been pressed into production. (Implicit approval from the significant other, if nothing else.) I do have access in between recordings/viewings if there is anything you would like tested.
>> 
>> For the record, my setup is Fedora 15 with updates
>> Was using ATrpm builds, but I had to rebuild Myth rpms from git source a couple days ago to get H.264 support capture support.
>> 
>> Let me know if you need anything else, thanks in advance.
> 
> No, that pretty well covers it. I'll have to steal my hdpvr out of production.
> That'll be easier once the Stanley Cup Playoffs are over (its recording the
> games that are on Versus HD), which should be RSN. I guess I could try to
> reproduce the issue with other zilog-based hardware too... Anyway, looking at
> this issue has been added to my TODO list.

I'm able to reproduce the problem with an hvr-1950, so I don't have to worry
about my hdpvr now. I was talking to Andy Walls about this issue last night,
and he reminded me of something that you can do that'll at least get rid of
the cpu usage issue for now... Load lirc_zilog with tx_only=1, and the rx
thread that is spinning will never get launched (this assumes of course
that you're not using the rx portion of the hdpvr).

Anyway, digging into the problem right now to try to isolate exactly where
its spinning.

-- 
Jarod Wilson
jarod at wilsonet.com