Determine whether RMF should monitor zFS file system activity by default
Description
The Monitor III data gatherer can be used to monitor zFS file system activity; this function is enabled or disabled through the options ZFS and NOZFS, which are set in ERBRMF04. Before z/OS V2R1, the default setting was ZFS. In z/OS V2R1, the default changed to NOZFS. Starting in z/OS V2R2, RMF introduces new Monitor III zFS sysplex reports that gather zFS performance data through new zFS APIs. As a result, the default Monitor III gatherer option is changed to ZFS.
Table 1 provides more details about this migration action. Use this information to plan your changes to the system.
| Element or feature: | RMF |
|---|---|
| When change was introduced: | z/OS V2R2. |
| Applies to migration from: | z/OS V2R1. |
| Timing: | After the first IPL of z/OS V2R2. |
| Is the migration action required? | Yes, if you do not want to collect data about zFS file system activity. |
| Target system hardware requirements: | None. |
| Target system software requirements: | None. |
| Other system (coexistence or fallback) requirements: | None. |
| Restrictions: | None. |
| System impacts: | None. |
| Related IBM® Health Checker for z/OS® check: | None. |
Steps to take
Follow these steps:
- Determine whether you want RMF to monitor zFS file system activity.
- If you want to always monitor zFS file system activity, no action is required.
- If you do not always want to monitor zFS file system activity,
then you can either:
- Specify the NOZFS option in the ERBRMFxx parmlib member, so it will always be in effect for all of your Monitor III data gatherer sessions.
- Use the MODIFY RMF,MODIFY III,NOZFS command during a running session.
Reference information
For more information about the NOZFS option, see z/OS RMF User's Guide.