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Re: [Discuss-gnuradio] Ring-buffer allocation
From: |
Marcus D. Leech |
Subject: |
Re: [Discuss-gnuradio] Ring-buffer allocation |
Date: |
Tue, 03 Feb 2009 16:52:34 -0500 |
User-agent: |
Thunderbird 2.0.0.18 (X11/20081119) |
Eric Blossom wrote:
>
> OK. It may no longer be double buffering, so your throughput may be
> down. But, hey, if it's working :-)
>
> Eric
>
>
OK, so I looked into this further. If I work backwards from the
file-sink back to the USRP, I have
a float vector of 16e6 items, which was costing 250e6, a complex
vector of 16e6 items, which was
costing 500e6, another 16e6 complex vector costing 500e6, and a
complex stream of 32e6 items, costing
250e6 memory.
I added logic to gr_flat_flowgraph::allocate_buffer so that if nitems
>= 4 and item_size >= 1<<2, then
nitems /= 2.
That reduced the memory footprint considerably, and still gives you
double buffering between blocks.
--
Marcus Leech
Principal Investigator, Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org