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Slow Allegro with 30k components

Biradin88

Hello,

When I try to quick place a huge amount of components, around 30k, it takes more than two hours to do so. The only resource taken during that time is a lot of RAM. CPU stays lower than 0.5% , no GPU used. Online DRC is turned off and dynamic shapes are off. After finally placing all components Allegro stays in unusable state: I can't click anything, nothing responds. Around 20GB of RAM are taken and still no CPU or GPU is used. Are there any tricks for working with big PCB-s like that? Any functions I should turn off? 

PC has 32 GB of RAM with i7 CPU and Windows 10 . After placing all of the components around 85% of RAM is taken (including all other processes) . 20 out of 32 GB for Allegro. Allegro(PCB Designer) is v17.4.

  • avant
    0

    You could try reducing the drawing extents. turn all layers on, zoom out, measure the used area and set this as the extents.

    This could reduce the file size of the board, but I don't know if it will help.

    Or, you could try quick place by schematic page, one page at a time.

  • DavidJHutchins
    0 in reply to avant

    Besides the total component count, can you provide a little more info from the 'summary drawing report', specifically the 'Layout Statistics' section, an example is shown below:

    Layout Statistics:
    Components: Placed(1023) Unplaced(0) Total(1023)
    Component Classes: IC(62) IO(52) Discrete(907) Mechanical(2) Other(0)
    Nets: W/Rats(814) No/Rats(1) Total(815)
    Pins: W/Rats(2843) No/Rats(1334) Unused(14) Unplaced(0) Total(4191)
    Equivalent ICs (1 pin = 1/14 EIC): 299
    RatTs: 0
    Router Keepin (in): (-0.1863,-0.1965) by (4.3013,2.7556)
    Layout area (sq in): 13.04
    Average ratlength (in): 0.5
    Rat density (in/sq in): 38.721
    Double-sided rat density (in/sq in): 19.360

  • RFinley
    0

    Honestly, there is a point where a MSWindows machine is not going to be fast.

    Try Allegro on RHEL(Linux).   RHEL OS is $300 and runs on intel/amd machines.

    www.redhat.com/.../red-hat-enterprise-linux-workstation

  • Vipulc
    0

    Check performance by disabling "Enable On-Line DRC" and "Enable On-Line DFM Checks". If this works then open your Analysis Modes, under Design and Electrical, check the box for Batch mode for the constrains not in frequent use.

    DRC check under Batch can be run from "Tools > Database Check".

    You can also try Performance Advisor that you can run from DBDoctor (Tools > Database Check).

  • harkris
    0 in reply to RFinley

    Turn off "Enable On-Line DRC" and "Enable On-Line DFM Checks" to see how well they work. If this works, go to your Analysis Modes and check the box for Batch mode under Design and Electrical for the constraints you don't use very often. backrooms game

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