Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Memory Block Utilization Removed?

I really hope this is something that I broke and not a feature removal in the latest Quartus. When I build a design and go to Resource Utilization by Entity report, there is no longer anything showing me how many memory blocks are used. I only see “Memory Bits,” but I have found that to be far less useful in practice (and sometimes extremely misleading). I always run out of blocks before I run out of bits since memory blocks aren’t generally used with 100% efficiency. If I make a FIFO that’s ten 16-bit words deep, it’s going to burn an entire memory block. I want to see that as 1 memory block in use, not “160 bits.”

Using that reasoning, why bother telling me how many 9-bit or 18-bit multipliers I’m using? Why not just say that my design multiplies 341 bits? The block count is important!

I thought maybe I just turned the memory block column off accidentally, but when I right click the column headings it does not show up as an option.

What happened?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    I'm looking at a Stratix V design in Q13.1 and have a column for memory bits and M20Ks. (And you're right, M20K is the only really useful one). What device/version?

    One thought is that you may not have a fit. The synthesis report doesn't show M20K, just memory bits, because the count isn't known until fitting is done. If you only run synthesis or get a no-fit, maybe it doesn't show up.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Thank you for mentioning fit/synthesis. I was having a brain fart last night. The design had a fit, I was just accidentally looking at the synthesis utilization report and not the fitter utilization report. When I go to the fitter report now, the memory block breakdown is all there. I just need to stop working so late.