Hello HangaS,

Have you been able to make any progress with locating a root cause and/or a bottleneck?

Did you try to isolate the problem by taking some systematic approach, e.g. checking SCSI bus termination, trying another tape drive, verifying your SuperLoader performance on a different system, etc.?

Frankly speaking it reminds me a tape drive shoe shining effect usually caused by insufficient data amount provided by the IO pipe. If you don't stream data to the drive it stops and before writing again it needs to reposition the tape. However this should not take "many many" seconds... unless you stop streaming data for "many" seconds.

Piotr