#47 XSpice memory usage (TRAN TSTART effect)

[Vito]

Hello I am trying to simulate a very large project for a very long simulation time (10 s), but only the latest 0.1 second is of interest.

So my statement is tran 16u 10s 9.9s uic

The project is mixed sim, I am using XSpice (version 30 with d_process).
I have noticed that the Event-driven portion always stores data from t=0, ignoring my TSTART value in TRAN: in fact the memory usage is very high (about 14GB ).

Is there anything I can do to force the discard of uninteresting event data by Xspice?

Thank you in advance,
--Vito.

[marcel hendrix]

On 2019-12-11 19:48, Vito wrote:

---

** [support-requests:#47] XSpice memory usage (TRAN TSTART effect)**

Status: open
Group: v1.0 (example)
Created: Wed Dec 11, 2019 06:48 PM UTC by Vito
Last Updated: Wed Dec 11, 2019 06:48 PM UTC
Owner: nobody

Hello I am trying to simulate a very large project for a very long
simulation time (10 s), but only the latest 0.1 second is of interest.

So my statement is tran 16u 10s 9.9s uic

The project is mixed sim, I am using XSpice (version 30 with
d_process).
I have noticed that the Event-driven portion always stores data from
t=0, ignoring my TSTART value in TRAN: in fact the memory usage is
very high (about 14GB ).

Is there anything I can do to force the discard of uninteresting
event data by Xspice?

Did you try NGSPICE -b ... | tail -n ... ?

-marcel

[Vito]

Yes Marcel thank you I tried that.
--Vito.

Il giorno mer 11 dic 2019 alle ore 20:49 marcel hendrix mhx_at_sf@users.sourceforge.net ha scritto:

On 2019-12-11 19:48, Vito wrote:

---

• [support-requests:#47]
  https://sourceforge.net/p/ngspice/support-requests/47/ XSpice memory
  usage (TRAN TSTART effect)*

Status: open
Group: v1.0 (example)
Created: Wed Dec 11, 2019 06:48 PM UTC by Vito
Last Updated: Wed Dec 11, 2019 06:48 PM UTC
Owner: nobody

Hello I am trying to simulate a very large project for a very long
simulation time (10 s), but only the latest 0.1 second is of interest.

So my statement is tran 16u 10s 9.9s uic

The project is mixed sim, I am using XSpice (version 30 with
d_process).
I have noticed that the Event-driven portion always stores data from
t=0, ignoring my TSTART value in TRAN: in fact
the memory usage is very high (about 14GB ).

Is there anything I can do to
force the discard of uninteresting event data by Xspice?

Did you try NGSPICE -b ... | tail -n ... ?

-marcel

• [support-requests:#47]
  https://sourceforge.net/p/ngspice/support-requests/47/ XSpice memory
  usage (TRAN TSTART effect)*

Status: open
Group: v1.0 (example)
Created: Wed Dec 11, 2019 06:48 PM UTC by Vito
Last Updated: Wed Dec 11, 2019 06:48 PM UTC
Owner: nobody

Hello I am trying to simulate a very large project for a very long
simulation time (10 s), but only the latest 0.1 second is of interest.

So my statement is tran 16u 10s 9.9s uic

The project is mixed sim, I am using XSpice (version 30 with d_process).
I have noticed that the Event-driven portion always stores data from t=0,
ignoring my TSTART value in TRAN: in fact the memory usage is very high
(about 14GB ).

Is there anything I can do to force the discard of uninteresting event
data by Xspice?

Thank you in advance,
--Vito.

---

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[Holger Vogt]

Vito,

there nothing what I can suggest to you.

This is on my list of items to be done.

Holger

[Vito]

Thank you very much Holger,

I must admit that I managed to compile ngspice in debug mode and I tried to
investigate if this could be done with a simple contribution,
but I stopped when I found the comment "data is stored for later use by
code models" in evtload.c.
So I suppose some code models could need some event history for
computation, despite the fact that such data is not requested by the user's
tran statement.
Is this right?

--Vito.

Il giorno mer 11 dic 2019 alle ore 20:51 Holger Vogt h_vogt@users.sourceforge.net ha scritto:

Vito,

there nothing what I can suggest to you.

This is on my list of items to be done.

Holger

• [support-requests:#47]
  https://sourceforge.net/p/ngspice/support-requests/47/ XSpice memory
  usage (TRAN TSTART effect)*

Status: open
Group: v1.0 (example)
Created: Wed Dec 11, 2019 06:48 PM UTC by Vito
Last Updated: Wed Dec 11, 2019 06:48 PM UTC
Owner: nobody

Hello I am trying to simulate a very large project for a very long
simulation time (10 s), but only the latest 0.1 second is of interest.

So my statement is tran 16u 10s 9.9s uic

The project is mixed sim, I am using XSpice (version 30 with d_process).
I have noticed that the Event-driven portion always stores data from t=0,
ignoring my TSTART value in TRAN: in fact the memory usage is very high
(about 14GB ).

Is there anything I can do to force the discard of uninteresting event
data by Xspice?

Thank you in advance,
--Vito.

---

Sent from sourceforge.net because you indicated interest in
https://sourceforge.net/p/ngspice/support-requests/47/

To unsubscribe from further messages, please visit
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[Holger Vogt]

Vito,

there might be one or the other XSPICE model with a need to have access to all data (I am honestly not aware of any), but this shall be a user decision:

Store data only for a specific time period
and/or
Store data for specific nodes only
or
Store all data

This is what we have in the analog world, and the same might be good for XSPICE as well.

Holger

[Giles Atkinson]

This should be fixed by change a40d1ba74edda3ecbd72428cb2c532543d74dd99 and previous changes from Patch 109.

[Giles Atkinson]

This should be fixed in ngspice 37.