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,

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,

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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