Very high bandwidth usage on idle (75Mb/s)

Martin Ayla

Thanks for a great program :)

I'm using a HDHomerun, latest Tvheadend Unstable and Ubuntu 12.04.

My Ubuntu machine, where Tvheadend is installed, is seeing very high bandwidth, both in and out, when Tvheadend is idle.

PS. EIT scanner is off. "Close on idle" is on.

Here is the output of iftop for eth0, the bandwidth usage stays like this 24/7. I hope there's a fix, so I don't have to waste bandwidth (my HDHomerun is not connected directly to the Ubuntu machine, so a lot of traffic travels over my LAN).

iftop -P -i en0:

tvheadend.local:47777                            => 10.0.1.6:5004                                        0b      0b      0b

                                                 <=                                                   37.4Mb  37.4Mb  37.4Mb

tvheadend.local:60907                            => 10.0.1.6:5004                                        0b      0b      0b
                                                 <=                                                   37.3Mb  37.4Mb  37.4Mb

Villy Thomsen

I got the same here.

First off, if you have the "full mux reception" option set to "auto" or "on" set that to "off". There is absolutely no reason to be streaming the entire mux, 30-40-50 mbit/sec per mux just to record one channel. (I would also argue that the default for that setting ought to be "off", it will only cause trouble for devices that can't handle it).

But, there is also a change in behaviour from 3.2 -> 3.4 that should be looked into. In 3.4 tvheadend doesnot remove PID filtering when a recording is finished. When starting a recording tvheadend will set a PID filter as it always has to say:

PidFilter: 0x0 0x1 0x10 0x11 0x12 0x4BA 0x4BB 0x4C3 0x79 0x1770 0x1771 0xC6 0xFA 0x104 0x111 0x137

Where 0x4BA, 0x4C3 and 0x4C3 is the channel/program being tuned to, and the rest is PMT, PAT and so forth. In 3.2 when the recording is stopped those "0x4BA, 0x4C3 and 0x4C3"" etc are then removed from the PID filter - this doesnot happen in 3.4.

The result being of course a system that is loaded more than it should be because we keep receiving the program/channel after a recording.

(and this is with idle tuning off, close on idle on).

Martin Ayla

Thanks for the reply.

Nice to see I'm not the only one experiencing this.

I tried setting full mux reception to off now, but it doesn't seem to make a difference for me.

I hope Adam can chime in, maybe giving some info on what the data is that is being transferred non-stop?

Villy Thomsen

Oh, that setting doesn't have effect untill after a restart of Tvheadend (at least it didn't for me).

The data being transferred is basically every single video/audio/teletext stream included in whatever mux/frequency you are tuned to. There is absolutely no reason to keep streaming it after a recording has ended, which is where the PID filtering problem I discovered comes into play. ;-)