Does anyone know more about "TAR nice priority"?

One of my customers is using tarring for his GWDR files. Unfortunately tarring takes a long time for one of his post offices - almost 96 hours. Unfortunately no backup jobs will run for this post office in the meantime.

So I am checking which possibilities I have to solve this issue. I.e. there is one setting called TAR Command Linux nice Priority.

However there is no documentation for this. So I opened a case - but support has to ask development; support did not even know that this setting exists.

Therefore my question - who has experience with this setting or who knows how to use?

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