Buffer Settings for Duplication to LTO 5 Tape
Created: 31 Jan 2014 • Updated: 04 Feb 2014 | 13 comments
This issue has been solved. See solution.
We're using a Netbackup 5230 Appliance connected via 8Gb fibre to an HP MSL 8096 LTO 5 tape library with 4 drives. I've read many posts recommending leaving the buffer size as default:
SIZE_DATA_BUFFERS : 262144 (Default)
SIZE_DATA_BUFFERS_DISK : 262144 (Default)
SIZE_DATA_BUFFERS_FT : 262144 (Default)
This is how they are currently set, and when monitoring backups to disk, I see the following in the log:
01/29/2014 19:49:09 - Info bptm (pid=3752) using 262144 data buffer size
01/29/2014 19:49:09 - Info bptm (pid=3752) using 30 data buffers
Which is expected, however, when duplicating to tape, the logs indicate the following:
01/31/2014 17:00:15 - Info bptm (pid=30607) using 65536 data buffer size
01/31/2014 17:00:15 - Info bptm (pid=30607) using 30 data buffers
Can someone clarify why it would be set this way and is this as expected?