ML_OUTBLOCK

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Revision as of 14:13, 20 March 2024 by Singraber (talk | contribs)

ML_OUTBLOCK = [integer]
Default: ML_OUTBLOCK = 1 

Description: Output distance in number of steps for molecular-dynamics simulations with machine-learned force fields in prediction-only mode (ML_MODE = run).

Important: This tag is only available as of VASP.6.4.0. Unfortunately, the implementation of this feature was incomplete before VASP.6.4.3. in VASP versions prior to 6.4.3 there was still substantial remaining per-time-step output, in particular in vasprun.xml and vaspout.h5.

By default VASP writes all results at every molecular-dynamics step (ML_OUTBLOCK = 1). However, this may become inefficient when running long trajectories in production runs with a machine-learned force field in prediction-only mode (ML_MODE = run). This is particularly true if the force field supports the fast execution mode, i.e., refitting was performed with ML_MODE = refit. Then, depending on the system size, writing output each time step may hinder performance, cause heavy I/O load and create unnecessary large files. In order to circumvent these problems ML_OUTBLOCK = n instructs VASP to write screen and file output only every n time steps.

In order to further increase the efficiency, calculation and output of pair-correlation functions can be completely switched off by setting ML_OUTPUT_MODE = 0.

Warning: This tag will potentially override defaults and INCAR values of NBLOCK! NBLOCK will be automatically set to the maximum of ML_OUTBLOCK and NBLOCK.

Related tags and articles

ML_LMLFF, ML_MODE, ML_LFAST, ML_IERR, ML_OUTPUT_MODE, NBLOCK