Recovery Scenario: Overestimated Compression Ratio - IBM Storwize V7000 Unified Problem Determination Manual

3. Right-click an unmanaged MDisk and select Add to Pool.
4. On the Add to Pool dialog, select the pool and click Add to Pool.
5. Verify that the MDisk was added to the selected pool by expanding the pool

Recovery scenario: Overestimated compression ratio

If you overestimate a compression ratio when planning compressed file systems,
you can run out of capacity and potentially lose access to file system data if the
compressed file system goes offline.
To correct this problem, you can either increase capacity to the underlying block
storage pool or decrease the size of the file systems before the file system goes
offline.
Increasing capacity of a storage pool
The simplest method for adding more capacity to the storage pool is to allocate
additional storage to the pool. There are three ways to add additional storage to
the storage pool. The first method assumes that MDisks have been created from
external or internal storage but have not yet been allocated to a storage pool. The
second method configures available disk arrays on internal storage into MDisks
which are then allocated to the storage pool. With the last method, capacity is
provisioned from externally attached storage and is added to the storage pool.
Add any available MDisks: If an MDisk has already been created but not assigned
to a pool, complete these steps:
1. In the management GUI, select Pools > MDisk by Pools.
2. Select Not in pool to display all the available MDisks that are not currently
3. Right-click the MDisks that you want to add to the storage pool and select Add
4. On the Add to Pool dialog, select the pool and click Add to Pool.
5. Verify that the MDisk was added to the selected pool by expanding the pool
Add any available drives: If MDisks have not been configured from available
internal drives, you can provision the available drives into existing storage pools
by completing these steps:
1. In the management GUI, select Pools > Internal Storage.
2. Select Configure Storage.
3. On the Configure Internal Storage dialog, select Select a different
4. Click Finish.
and ensuring that the added MDisk is displayed.
allocated to a storage pool.
to Pool.
and ensuring that the added MDisk is displayed.
configuration and complete the following steps:
a. In the Drive Class field, select the drive class that is available based on the
installed storage on the system.
b. In the Preset field, select the RAID configuration for the storage you are
configuring.
c. Select Optimize for capacity to configure all available capacity.
d. Verify the configuration and click Next.
e. Click Expand an existing pool and select the storage pool that is used for
compression.
Chapter 8. Troubleshooting compressed file systems
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