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If you are accessing a large file (1GiB+) from multiple nodes in parallel, please consider to activate striping of the file with the Lustre command lfs setstripe (specific to this file or for a whole directory, changes apply only for new files, so applying a new striping to an existing file requires a file copy) with a sensible stripe_count (recommendation: Emmy up to 32, Lise up to 288) and a stripe_size, which is a multiple of the RAID6 fullstripe size and matches the IO sizes of your job.
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