Slow server for the next 8 hours or so...
GeorgeM, the machine that holds the data that you download, decided that it was time to verify that the RAID array is in good shape. That will slow down disk access until the verify procedure is complete. The main effect is slowing down the rate at which work can be created. It's likely that we'll run out of work in the next hour or so. Things should recover automatically when it's done.

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