File I/O Operatons

[BDMcGrew]

Hello all...

While doing a mig stg from disk to tape, and watching the logs, I'm seeing where TSM (7.1.5/Linux) is opening and closing two separate disk volumes on average at once a second. A snip from the log file is attached and while watching it scroll, it happens so fast you can't read it. Just trying to migrate a storage pool to tape so I can upgrade a disk.

Are there any tunables that I can adjust to allow TSM to have multiple disk volumes open for a migration at the same time???

See below..

ANR0515I Process 11 closed volume /tsm/volX/00000496.BFS.
ANR8340I FILE volume /tsm/volX/000004A3.BFS mounted.
ANR0512I Process 11 opened input volume /tsm/volX/000004A3.BFS.
ANR0515I Process 11 closed volume /tsm/volX/000004A3.BFS.
ANR8340I FILE volume /tsm/volX/00000496.BFS mounted.
ANR0512I Process 11 opened input volume /tsm/volX/00000496.BFS.
ANR0515I Process 11 closed volume /tsm/volX/00000496.BFS.
ANR8340I FILE volume /tsm/volX/000004A3.BFS mounted.
ANR0512I Process 11 opened input volume /tsm/volX/000004A3.BFS.
ANR0515I Process 11 closed volume /tsm/volX/000004A3.BFS.

 

[DazRaz]

Is this causing an issue? I would have thought it was best for it to have open as few volumes as possible as these volumes are not available to other processes or sessions while the migration has them open.

I believe you are best to ignore it.

 

[BDMcGrew]

Got it, thanks! The only "problem" that it might be causing is it's happening so fast I have to believe it's underrunning the library and shoeshining the tapes. Other than that concern, there is no real problem.

 

[moon-buddy]

Got it, thanks! The only "problem" that it might be causing is it's happening so fast I have to believe it's underrunning the library and shoeshining the tapes. Other than that concern, there is no real problem.

I don't understanding what you mean by "shoe shining the tapes" as the snippet says xxx.BFS which means these are file volumes on disk and not on physical tape. Thus, shoe shining is NOT happening.

 

[BDMcGrew]

In the original post, I said I'm migrating a storage pool from disk to tape so I can place a hard drive.

While reading the volumes from disk and while writing to tape, TSM is flip flopping back and forth between the same to disk volumes opening and closing them on average of once per second (my guess is the data is fragmented). Because of having to switch volumes so frequently (once a second) I'm concerned about keeping the buffer pools for the tape library full.

 

[moon-buddy]

In the original post, I said I'm migrating a storage pool from disk to tape so I can place a hard drive.

While reading the volumes from disk and while writing to tape, TSM is flip flopping back and forth between the same to disk volumes opening and closing them on average of once per second (my guess is the data is fragmented). Because of having to switch volumes so frequently (once a second) I'm concerned about keeping the buffer pools for the tape library full.

Disk is a lot faster and can address the buffer needs of the tape drive. Like what DazRaz said, this can be ignored.