Hourly output when running ORCA025

Dear all,
I run experiments with ORCA025 configuration and I have recently faced problems when setting “1h” as output frequency (both with instantaneous and average output values).
The simulation is OK and no problems are found in the ocean.output files; however, the output files of simulation are not produced and the following error is repeated in the nemo.out file changing the event size and the server name

-> error : WARNING: Unexpected event of size 127 for server 0 (estimated max event size = 112)

This error does not show up with a different output frequency (from 2h to 1d).
I have tried to use different numbers of processes but result doesn’t change. I am using the trunk of the XIOS.

Does anyone have experienced something of similar when asking for hourly output frequency?
Thank you in advance,
Francesco

Do you use XIOS in detached mode?

  • If not, you should.
  • If yes, you should play with the number of XIOS processes (use more) and try to distribute the XIOS processes among the NEMO processes. For example spread 1 or 2 XIOS per node instead of putting all XIOS processes together…

Thank you Sebastien for replying.
Yes, I have used XIOS in detached mode. I have tried your suggestions; however, the problem was a bad behaviour of XIOS when writing multiple files. I was able to fix it by rewriting the file_def-oce.xml file asking only a single output file.

Many thanks,
Francesco

Apparently you did solve the problem. A small remark related to this post for people attempting to write high frequency outputs and seing weird results: your output period must be a multiple of your model time step…

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