[SOLVED] Transient Simulation (Virtuoso Spectre) consumes huge file-size

[ahmad.mar]

Dear All,

I am running some small-size transient simulations using Spectre simulator in Virtuoso.
that includes some veriloga blocks and a small transistor level one.

Although, through the ADE window save options, I disable all saving of nodes/currents/variables I am still getting a huge and fastly increasing file size for the file "tran.tran.dat"

do anybody knows if there are other options to disable this huge data saving through the transient simulation?!

as I included before, I do not need any node to be saved because I am saving the needed output directly through a veriloga model in a file.

Thanx in advance

 

[erikl]

A possible workaround:

Somewhere in your Spectre simulator control files' setUp you might find a Unix/Linux command
................... > tran.tran.dat
replace it by:
................... > /dev/null

You have to make sure that a new simulation run doesn't overwrite this change.

A few years ago, this workaround was successful.
---------------------------------------------------------------------------------------------------------
A simpler solution would be to find and change - or insert - the control statement

tran info where=nowhere

s. this Spectre Circuit Simulator Reference snippet: View attachment SPECTRE_output_to_nowhere.pdf

 

[dick_freebird]

You might inspect for unusually "busy" nodes which may be forcing
timestep downranging and data bloat - they could be behaving
unrealistically in other ways as well. I occasionally managed to choke
Spectre on big jobs with a high mix of low speed analog and high
speed clocks and long run intervals, but normally the data pile size
has not been anything more than an occasional housecleaning
nuisance (have to clean the /simulation/*/*/*/tran.tran files out
every few months).

It got to the point that I identified all of the places that data
bloat collects (parametric analysis is a really bad actor, esp.
with nested loops - J*K*L*M times the problem and all with
machine generated file structure that you have to abstract)
and made some shell script that auto-ream the /simulation
directory. So when I see the /simulation approaching its
allocation limit, I have to take a minute out of my day and
fix it.

 

[kemiyun]

Actually, a simulation log would be helpful in defining the problem. Can you provide one?

 

[ahmad.mar]

well these comments seem useful. I will try this workaround suggested by erikl.

However, I got a good workaround "offline" from my senior colleague, and here I post it in case anybody face this again in future;

basically with Spectre simulator under virtuoso it seems not good not to save any data, because then the simulator will save a lot of -useless- data.

very simply, the solution was to pick a voltage node which is not or very rarely changing, gnd for instance, and select to save only this node.
Then I noticed the tran.dat file has a way smaller size than when no node was saved (from ~30 GB down to ~500MB).


and I may try also erikl's suggestions that probably could exclude the whole file!