[mythtv] HD3000 buffer overrun solution - patches for hdtvrecorder.cpp/.h against mythtv 0.16

[Taylor Jacob]

> A drive can sustain that at times, but not always.  If you are writing a
> single file and the head of the driver does not have to move except
> where it's writing then it's easy to get that speed.  Once you add 3
> streams being saved to different possitions on the disk you loose a lot
> of throughput in the head of the drive moving.  If you're reading a show
> from disk you're possibly moving the head quite a ways.  If you're
> accessing other data randomly from the disk for whatever reason, .. you
> get the point.  So writing data is a problem.  -- And it's not always
> the disk.

I am aware that sequential writes are always going to be much faster than random
read/writes but I still do not understand how there is a problem here..

> What I personally see is on AMD XP mainboards, you
> sometimes can max out the system bus.  Each tuner card dumps a 45mb/s
> stream (This can be fixed in the driver, to only send a single stream,
> instead of the entire ATSC stream for a channel, so 4.5mb-19.4mb.

Why does the pchdtv send a stream that is more than twice the bandwidth of ATSC?
 Where are you getting these numbers from? I have to assume you mean megabit..
But it seems like you are mixing and matching units here.. Because even a 150
megabit stream shouldn't slam a pci bus.