I have a TSM 6.4 installation backing up to a Protectier VTL containing 3500+ cartridges of 50Gb (capacity reported by the VTL per cartridge is 51200MB)
But TSM marks tapes as 100% full at occupancy levels varying between 30 to 50GB. Estimated tape size in TSM is also set to 51200MB and so are the estimated sizes of scratch tapes in TSM.
I don't know if it is actually related but we where coming from a configuration where the tape sizes where set to 300 Gb but due to the long reclamation processes we decided to replace all cartridges with 50Gb as recommended by IBM (they recommend 50Gb to 100Gb cartridges in a VTL) and removing the 300Gb cartridges as they became free. However during this process the VTL has been temporarily overcommitted to be able to easily automate this process and the actual cartridge size was hereby temporarily reduced to 30Gb/cartridge by VTL, but now that all old 300Gb tapes are all removed the capacity/cartridge is now correctly at 51200MB/cartridge according to the VTL..
I have been moving tape data within the library for all tapes marked as full with an estimated size < 40GB to be moved to new scratch tapes hoping they would then fill up to 50Gb.. And by the end of the day the actual amount of tapes marked as full with an estimated capacity of less than 40Gb is almost zero and I get a lot of extra scratch tapes.. However, the next day (after nightly backups where taken) there are always 300+ cartridges again marked as full with only an estimated capacity between 30 and 40Gb... Leaving me with a lot of 'wasted' space unavailable for TSM until these tapes' data are again moved within the library to scratch tapes.
What makes TSM marking those tapes a full before they reach an occupancy of 50Gb, the actual capacity of the cartriges? Is the VTL incorrectly reporting the tapes as full to TSM? Or does TSM 'remember' that it could only place about 30 to 40 gb on those tapes previous time, and now also marks them full, despite the fact that it reports 50Gb estimated capacity when they are in scratch state..
I have currently no idea how to find answers to those questions, and how to make TSM fill all tapes up to their full capacity..
We are not using colocating, TSM dedup or compression. Dedup is handled by the VTL and the library type for this VTL in TSM is set as VTL.
Does anybody know what is happening here ?
But TSM marks tapes as 100% full at occupancy levels varying between 30 to 50GB. Estimated tape size in TSM is also set to 51200MB and so are the estimated sizes of scratch tapes in TSM.
I don't know if it is actually related but we where coming from a configuration where the tape sizes where set to 300 Gb but due to the long reclamation processes we decided to replace all cartridges with 50Gb as recommended by IBM (they recommend 50Gb to 100Gb cartridges in a VTL) and removing the 300Gb cartridges as they became free. However during this process the VTL has been temporarily overcommitted to be able to easily automate this process and the actual cartridge size was hereby temporarily reduced to 30Gb/cartridge by VTL, but now that all old 300Gb tapes are all removed the capacity/cartridge is now correctly at 51200MB/cartridge according to the VTL..
I have been moving tape data within the library for all tapes marked as full with an estimated size < 40GB to be moved to new scratch tapes hoping they would then fill up to 50Gb.. And by the end of the day the actual amount of tapes marked as full with an estimated capacity of less than 40Gb is almost zero and I get a lot of extra scratch tapes.. However, the next day (after nightly backups where taken) there are always 300+ cartridges again marked as full with only an estimated capacity between 30 and 40Gb... Leaving me with a lot of 'wasted' space unavailable for TSM until these tapes' data are again moved within the library to scratch tapes.
What makes TSM marking those tapes a full before they reach an occupancy of 50Gb, the actual capacity of the cartriges? Is the VTL incorrectly reporting the tapes as full to TSM? Or does TSM 'remember' that it could only place about 30 to 40 gb on those tapes previous time, and now also marks them full, despite the fact that it reports 50Gb estimated capacity when they are in scratch state..
I have currently no idea how to find answers to those questions, and how to make TSM fill all tapes up to their full capacity..
We are not using colocating, TSM dedup or compression. Dedup is handled by the VTL and the library type for this VTL in TSM is set as VTL.
Does anybody know what is happening here ?