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tvheadend generating high system load

Added by Martin Mrvka over 10 years ago

Hi.

Maybe I need to be more precise by saying that the DVB drivers seems to be the cause of this.

The load is generated due to a high rate of interrupts and context switches, when running with a configured DVB adapter. I'd like to ask if someone else experiences the same issues.

I'm running a x86_64 ubuntu natty with v4l-dvb-dkms from ppa:yavdr/main. The DVB adaters are one Hauppauge HVR4000 (cx88) and two Technisat Skystar HD2 (mantis/stb0899). The behavior is also present, when running with the cx88 based card only (knowing that mantis driver has issues with interrupts).

Without tvheadend accessing the adapters, the system has about 200 interrupts/sec and 200 context switches per sec. When starting with the card HVR4000, the interrupts increase to 450 interrupts/sec and the context switches get up to 800 context switches per sec.

"idle scanning", "signal monitoring" and "autodetect muxes" is turned of and no client is connected.


Replies (3)

RE: tvheadend generating high system load - Added by Martin Mrvka over 10 years ago

Actually, I found the problem is related to the mantis based cards.

However I don't understand, why tvheadend is accessing the mantis cards (and they are generating the load) when the system should be idle.

Are there any epg scans or similar running anyway?

RE: tvheadend generating high system load - Added by JayJay - about 10 years ago

I have two DuoFlex S2 adapters from Digital Devices and also a "high" load in idle-state (load average: 0.42, 0.45, 0.44).

RE: tvheadend generating high system load - Added by Martin Mrvka about 10 years ago

I've replaced the two Technisat Skystar HD2 with two Tevii s480 and, besides that they are dual tuner, they are working great. After turning "idle scanning" off, I've an idle load of 0.08, 0.08, 0.08. So the card (and/or driver) was the problem.

Strange thing though, that without configuring the cards for tvheadend, the load was low. So I assume that the mantis/stb0899 driver started to do weird things when the device just was opened even if there was no additional access.

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