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placeDesign runTime is 90+ Hrs.

gpremala

PlaceDesign is taking 90+ Hrs to finish the job, and after that if i check for checkPlace I am getting violations

Violations like Overlapping 20K+ instances, region/fence 0.4M Instances, Orientations 0.4M Instances

All the standard cells are placing together and they are not uniform distribution.

The Design has 2M instances and 400+ macros.

EDI version is 10.13

Please suggest me to resolve this issue.

 

  •  Hi gpremala, 

       There are multiple inputs you might want to check in the logfile & design partioning .. !! 

       to me , 2 M instances & 400 memories are bit on a high side to approach for Top-Down Flat Methodology.

       May I know the below items to understand the constraints of your design/block ?

       1) Design PPA targets?

       2) What is the initial utilization you have started with?

       3) Since 400 Memories are too high in number for any given block, Did you specify the soft blockages on the macro channels ?

       4) Are you targetting for MMMC mode if so , how many modes & corners ?

       5)  Is your block DEF shape is rectilinear or a regular shape with enough routing resources?

       6) Are there any gross timing violations ? What is the slack for the register to register timing in preplace analysis ?

       7) Did you manage the weights on the interface path groups?

    Thanks

    suresh  

  • Hi Suresh,

    For,
    2) Initial utilization is 25% and after macro place 30%
    3) macro channel is 20um.
    4) 2 modes and 2 corners.
    5) rectilinear
    6) 0.200ns for R2R
    7) 0.45ns for i2r, 0.48ns for r2o

    Thanks,
    Gopi
  • Hi Gopi,

    below are the few experiments that you can chose to implement..

    1)  Run the placement without any constraints ..!! That gives you the best area ... !!
    2)  Run the placement with Rectangular DEF ( this gives a picture whether the block shape is a problem)
    3)  Try the option of Breaking the Block size into manageable pieces
    4)  Reduce weights on the i2r & r2o Paths ..
    5)  Analyze if any of your optDesign attributes are kicking up this problem
    6)  How is your congestion maps look like?

    Thanks
    suresh

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