On 30 Sep 2016, at 16:04, dumsani <g14n8326@campus.ru.ac.za> wrote:

Hi,

When running long simulations with checkpointing, it might sometimes be
useful to change certain parameters, especially I/O (e.g. the frequency
of outputting a certain variable). Is this possible in
Cactus/Simfactory? I notice that upon recovery (in the next re-start)
Simfactory reads the parameters from a checkpoint file, not from any of
the parfiles dumped within the job directory.

Any suggestions/responses will be highly appreciated.

Hi Dumsani,

When you run the simulation again, you give it a new parameter file.  It is this new parameter file which is checked for steered parameters; Cactus doesn't look at the output from a previous run.  Many parameters can be steered on recovery in this manner, by changing them in the parameter file.  Be careful when steering the out_every parameters; you almost certainly want out_criterion = divisor, not the default of "iteration".  "iteration" outputs if the current iteration number is N greater than the last output iteration.  "divisor" outputs if the current iteration is divisible by N.

-- 
Ian Hinder