On 12/03/2024 17:59, Rob Kossler wrote:
I think I am mistaken. If you are only streaming a single channel, the --multi_streamer option will likely not change a thing. I was assuming you had multiple channels.
Rob
Indeed, the problem doesn't appear to be "getting samples off the wire and into the application" (as evidenced by   the benchmark_rate runs), but rather "doing things with those samples after that".

Writing 2Gbyte/second through the filesystem interface to the kernel is....challenging.



On Tue, Mar 12, 2024 at 5:40 PM Rob Kossler <rkoss...@nd.edu> wrote:

    Your mount command with tmpfs looks correct. Here is what mine is
    in my /etc/fstab file (with 264GB avail RAM)
    tmpfs  /media/ramfolder/  tmpfs  rw,nosuid,nodev,size=200G   0  0

    You might want to try rx_samples_to_file with the --multi_streamer
    option. I expect you will get better performance.  Also, you can
    take your RAM FS size higher from 8G to probably 60G if you want
    to try bigger recording depths.
    Rob

    On Tue, Mar 12, 2024 at 5:13 PM Marcus D. Leech
    <patchvonbr...@gmail.com> wrote:

        On 12/03/2024 16:11, zackk...@utexas.edu wrote:

        Hey Rob and Marcus,

        Thanks for the responses! I have a basic understanding of
        linux, but am not very experienced. I tried the following to
        create the RAM filesystem:

        |sudo mount -t tmpfs -o size=8G tmpfs /mnt/tmpfs/|
        |sudo mount -t ramfs -o size=8G ramfs /mnt/ramfs/ |

        And ran the rx_samples_to_file, once with --file
        /mnt/tmpfs/test.bin, and once with --file
        /mnt/ramfs/test.bin, both times still getting o’s for overruns.

        By my calculations, at ~500 M complex samples per second,
        each complex sample 4 bytes (defaulting to short for I and
        Q), that means just 1 second of capturing equates to 2 GB of
        data. My system has 64 GB of RAM. Am I creating the RAM
        filesystem correctly? Am I using it correctly?



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        Assuming that you did a "sudo mkdir of /mnt/ramfs"
        beforehand,  this should work.


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