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Altera_Forum's avatar
Altera_Forum
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16 years ago

How to determined the physical memory used

How do we determine how much physical computer RAM is being used by each module of Quartus (i.e. Analysis & Synthesis, Fitter, Assembler, TimeQuest, etc.) during compilation?

Also, if the computer runs out of physical RAM, then it can go to the hard disk to access swap memory. How do we determine how much hard disk swap memory is being used by each module of Quartus during a compile?

Trying to look in the Flow Report (.flow.rpt) and it indicates Peak Virtual Memory for each module, but we don't know if that is physical RAM being utilized, or hard disk swap, or a total of both.

Also, if we execute a Quartus module individually via a command line (i.e. quartus_sta) will a .flow.rpt be output so that we can see how much memory is being utilized by that module you just manually ran?

Appreciate if anyone can help on this ASAP.

Thanks

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    also if we got

    Out of memory in module quartus_sta (2147 megabytes used)

    Does that mean that quartus_stat used or requied 2,147 Mbytes (17.176 Mbits) of physical RAM for this specific execution?

    Thanks if any one can help to clarify
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    The peak virtual memory reported in Quartus is a total of all the memory allocated by that executable. In general, disk swapping will slow down your compilation significantly, so having a machine that has enough physical RAM is important. Altera publishes recommendations on how much memory you need depending on the device you are using (see the release notes for the Quartus version you are using).

    When you run out at ~2 GB, it is usually a sign that you are using a 32-bit Windows machine, where Quartus typically has access to only 2 GB of RAM. There is an option to change XP to give you access to 3 GB, but it often makes your machine unstable. 32-bit Linux gives you access to 3 GB.

    For designs that need more than 2 or 3 GB, the solution is to upgrade to a 64-bit capable OS, use 64-bit Quartus, and have enough physical RAM to match the Altera recommendations.
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    for what its worth i don't think Quartus swaps very much. if it did, i wouldn't expect to ever run out of memory even on 32-bit Quartus, just have my compile take much longer

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Thanks for the information on the peak virtual memory. we also have the information on the amount of recommended memory and what OS to use.

    But does Quartus actually breakout somewhere how much of the peak virtual memory used, at the time for the individual module, is physical RAM andhow much is the swap?