Dear Itaru,

we have created the new I/O infrastructure (and the SIONlib backend in particular) to address exactly the problem you describe. It is available in NEST master since quite some time and the user-level documentation can be found here:

In order to enable it, you first install SIONlib (see this script for an example on how to do that) and then pass the path to NEST’s CMake using the --Dwith-sionlib=<path>.

Once everything is installed, you can just set the record_to property of any recording device to sionlib to let it write to SIONlib binary files. A minimal reader for the files can be found here:

Please let me know of any problems you run into. As this is quite new and has not been tested extensively in the wild, there might still be some glitches.


On 09.10.20 08:55, Itaru Kitayama wrote:

Has anyone explored the external library support? I am on Fugaku and
the jobs can create casually tens of thousands of files in a single directory;
this aborts jobs.

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