Re: [Discuss-gnuradio] Effect of having multiple throttle in a chain of flowgraph

[Ed Criscuolo]

On 1/31/12 5:41 PM, محمد روسلي wrote:
> Hi,
>
> I would like to ask what happen if there are many block of throttle
> connected between a source and a sink in pure simulation? I notice the
> GUI Interface (wxgui) is getting slow when 5 throttle block is connected
> between a signal source and signal probe sink.
>
> | Signal Block | ---> | Throttle | ---> | Throttle | ---> | Throttle |
> ---> | WX GUI Scope Sink |

The GUI slowing down is understandable.  You're doing a lot of extra 
work for nothing.  As Tom said, you only need one rate-limiting block 
per flowgraph.

In addition to the extra work, you're introducing a lot of extra latency 
for no reason, because each interface introduces another 32k sample 
buffer.  This becomes particularly noticeable at low sample rates.

For example,  at a sample rate of 9.6k, each 32k buffer introduces an 
additional 3.1 SECONDS of latency! (1.04 ms/sample x 32k samples).

@(^.^)@  Ed