recording on a raspberry pi

DJ Jo

I finally got my raspberry pi working as tv receiver. with 4 dvb-t receiver on a usb hub.
based on raspbmc but xbmc not started. I got the 256 ram version of the raspberry pi with gpu_mem_256=32

because of the stability my rootfilesystem (/) is on nfs.

I can stream 4/5 different channels. my memory use is <5%
But when i record a program, i see the use of (ram) memory rise til 80%. and it goes on his swap (a 6g partion on my sd card)

when the raspberry pi writes on his swap i becomes terrible slow ans incontrolable.

I tried aother Media container but no difference. it looks like the hole recording is on his ram and swap.
how can I make this better. (HTS Tvheadend 3.2.18~g40a8920-dirty)

Adam Sutton

Data will be buffered (unlimited) in RAM while its waiting to be written to disk. It's assumed that disk IO should not be a limiting factor (and thus this buffer will remain fairly limited) since most people either record to a local disk or across a fast ethernet connection.

Although 4-5 streams (even HD) should be within the realms of possibility on a 100Mb network connection, I believe the Ethernet controller on the rpi is actually hanging off the USB bus. It's possible that you're simply trying to do too much for the pi to cope with. Data shovelling has never been one of its strong points I don't think.

Adam