Commvault is showing 75 TB of data to be written to tape. We have set the tape copy to be “combine source data streams” to 3 (so it will use 3 tapes) and multiplexing is set to 5.
Additionally: We have the “Data Path configuration” set to use alternate Data paths when ‘resources are busy”, and (in the policy) checked “enable stream randomization...” and “distribute data evenly among multiple streams...”
Started the job, it chose to only write to 2 tapes, and also chose an alternate media agent to use (not sure why, the default media agent has 2 available tape drives and does not appear to be busy).
Looking at the job, it only used 7 readers BUT there is a single stream/entry for ‘media not copied”… it does not seem to have determined it needed to use 3 streams.. yet it has a single stream “waiting” … and its not writing “10 readers” (only 7)… so the reader counts/multiplexing seems to not be honored ( as there is a single stream waiting in ‘media not copied”.
why didn’t it break up the streams/multiplex so it would write to all the available tapes (3)? why is 1 stream configured to hang out and wait?
Also: the stream ‘waiting” is in “stream 2”. the tapes that are writing *does* have 5 readers for stream 2 so it might make sense for this waiting stream… BUT the other stream/tape only has 2 readers… why didn’t the streams all get assigned evenly so they could all write? It seems the system would have evenly allocated the streams/readers.
Best answer by Mike StrueningView original