SOLVED: The CF causes processor overload

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mihaid

Active Member
I assume it will be a hardware limitation. It seems to me that Humax specify the machine to be able to do the the maximum load the standard firmware will allow eg simultaneously recording two HD streams and playing back another HD stream plus maybe a bit of allowance for DLNA playback. Of course the custom firmware can impose a much higher load. The first candidate to investigate would I guess be the CPU.
shall i take it that all custom firmware users get the fairly frequent breakup of image/sound?
 

MymsMan

Ad detector
shall i take it that all custom firmware users get the fairly frequent breakup of image/sound?
No, every user has different experiences.

I use detectads chaserun on all non-BBC recordings and allow auto processing to run during recordings and rarely see problem unless I am deleting recordings or running something heavy duty via telnet but I tend to mainly record SD rather than HD.

Other users see more problems which is why there are options to defer auto-processing during recordings and at specific times of day

What is your auto processing frequency - does it correspond to the spikes you are seeing and does changing the frequency alter the spike frequency.
 

Black Hole

May contain traces of nut
shall i take it that all custom firmware users get the fairly frequent breakup of image/sound?
Not me! I guess it depends how heavy a user you are. If you want to know whether the CF is the culprit at all, disable it and see what happens.
 

af123

Administrator
Staff member
Not me! I guess it depends how heavy a user you are. If you want to know whether the CF is the culprit at all, disable it and see what happens.
Yep, that's exactly what the "Safe mode" is for, it just temporarily switches off most CFW components (apart from a small web server that allows you to get back out of safe more when you want)
 

/df

Active Member
now sysmon is showing me that every 15 or 20 mins there is a spike of about 75% of cpu usage. is there a log which identifies which processes could be causing the spike? just as the "top" command identifies them.
Is there a tooltip on the Sysmon CPU graph that shows the top process? I don't have one to hand but seem to recall this.
 

MymsMan

Ad detector
Is there a tooltip on the Sysmon CPU graph that shows the top process? I don't have one to hand but seem to recall this.
No, I think only the percentages are logged and not the detail
1581420862099.png
The Green Wait areas correspond to a period 10-11am when I had two recordings to a NAS drive in progress and the larger spikes correspond to Auto processing which, for me, runs every 12 minutes even while recording

I should be possible by extracting the data in from monitor.db to compare the peaks with the log records in auto.log (with detailed logging turned on) and then identify which phase of the auto process had the highest impact.

However I leave that as an exercise for the reader since
  • I have other things I should be doing
  • Auto processing doesn't cause problems with my usage
  • It is easy to turn Auto off during recordings if you think it does
  • If you see high CPU (>50%) with auto turned off we will need to find other ways of identifying the culprits
    For example see https://askubuntu.com/questions/22021/how-to-log-cpu-load
 
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OP
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mihaid

Active Member
If the auto process happens every 15 mins or so, why does it make a difference watching live no breakups and recording the same stream having breakups
 

MymsMan

Ad detector
If the auto process happens every 15 mins or so, why does it make a difference watching live no breakups and recording the same stream having breakups
It was your preconceived belief in starting this thread that high processor utilisation was the cause of your breakups, if you cannot correlate the times of your breakups occurring with periods of high cpu activity then this may be a misconception and you need to look elsewhere for the root cause.

Using Safe mode as mentioned earlier will help decide whether or not the CF is implicated.

Most users don't see regular picture breakups on recordings - there would be far more complaints - so there is something different on your system if you are seeing regular problems.
 

/df

Active Member
As before, the fact that this happens on write and not read may indicate that the disk is having trouble writing (perhaps there are borderline bad sectors?) and so other I/O operations, such as reading the data to be displayed, are being queued behind such writes. The disk should have some tolerance of AV errors, but heavy I/O demand from auto-processing, tvdiary, etc, might break the camel's back.
 
OP
M

mihaid

Active Member
It was your preconceived belief in starting this thread that high processor utilisation was the cause of your breakups, if you cannot correlate the times of your breakups occurring with periods of high cpu activity then this may be a misconception and you need to look elsewhere for the root cause.

Using Safe mode as mentioned earlier will help decide whether or not the CF is implicated.

Most users don't see regular picture breakups on recordings - there would be far more complaints - so there is something different on your system if you are seeing regular problems.
Or people just put up with it as I have for the past year or so before I complained
 
OP
M

mihaid

Active Member
Yep, that's exactly what the "Safe mode" is for, it just temporarily switches off most CFW components (apart from a small web server that allows you to get back out of safe more when you want)
Just can't find this safe mode switch. Is it the cf reset button?
 

prpr

Well-Known Member
There really is no excuse for anybody not to be on 3.13 at all.
And there's really no excuse for not checking you're up to date before posting questions like those up thread and wasting everyone's time, yours included.
 
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