When a large number of backup jobs that target the same disk-based storage device are
scheduled to start at the same time or within a small window of time, the following issues occur:
• The target device is underused with respect to the number of streams.
• Some jobs remain in the “Waiting for media” state even if the device can run parallel jobs.
• The completion time for small jobs increases by a few seconds or minutes.
These issues occur because the Media Manager uses a “quiesce time” setting to prevent assigning too many simultaneous jobs to a disk-based backup device. By default, the quiesce time is set to 10 seconds. Thus, after a job is assigned to a disk-based storage device, the Media Manager waits for 10 seconds before assigning the next job to the same device. You can change the default setting for quiesce time in the mediamgr.cfg file.
To change quiesce time for disk-based storage devices
1) Open the mediamgr.cfg file in a text editor. You can find this file in <NetVault Backup home>\config on Windows and <NetVault Backup home>/config on Linux.
2) Change the value for the following entry:
[Media Requests:RAS quiesce time]
Type=Range
Range=0,1000
Value=10
The default value is 10. To start the jobs at the same time, set the value to 0 (Value=0).
3) Save the file.
Note the following:
• This setting applies to all disk-based storage devices (DR Series Systems, EMC Data
Domain Systems, and NetVault SmartDisk devices).
• For shared NetVault SmartDisk devices, this value cannot be set to 0.
• On NetVault Backup 10.0.1.38 and previous versions, the quiesce time can only be set to
0 or 10. If you specify any other value, NetVault Backup uses the default value (that is, 10 seconds).
