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IES ml_uvm XMAXSTRSZ packer error


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I am migrating my uvm1.0ea code to uvm1.1.

I use ml_uvm to communicate with sysc models.

Using uvm1.0ea (and the ml_uvm that came with it) worked just fine.

Now when I migrated by code to uvm1.1, I get this error:

UVM_FATAL @ 55: reporter [XMAXSTRSZ] Packed ML UVM/OVM transaction size exceeded maximal stream size

This is happening on the first transaction that is sent to sysc.

When I disable this transfer of transaction from SV to sysc, my uvm1.1 test envinormant works as intended, i.e, all sequences finish and test finishes as I would expect.

So to debug further, I started played around with the ml_uvm examples that are shipped with IES.

Mainly with sv_to_sc_demo.sh and sc_to_sv_demo.sh (in uvm-1.1/uvm_lib/uvm_ml/examples/ex_e_sv_sc_tlm)

I found that sc to sv (i.e sc acting as producer) has no limit on the packed data (I experimented with a bit vector upto 9000 bits).

On the other hand sv to sc (sv acting a producer) errors out far below 4096 (I assume packer also packs data types).

I tried searching for the string in XMAXSTRSZ in uvm-1.1 directory but no luck.

Do you have any suggestions ?



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The transaction size in ml-uvm is always limited for performance reasons. You can change the limit using UVM_PACK_MAX_SIZE as follows:

% irun -defineall UVM_PACK_MAX_SIZE=<value-in-bits>

The problem you experienced does not seem to be related directly with the UVM version change but there was a performance optimization introduced in IUS 10.2 update version which may require larger UVM_PACK_MAX_SIZE.

Please try to use this switch and see if it solves the problem.

Best Regards,


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