---
title:  General Region Data Management
---

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For all regions, you have options to control memory use, back up your data to disk, and discard stale data from your cache.

-   **[Persistence and Overflow](../developing/storing_data_on_disk/chapter_overview.html)**

    You can persist data on disk for backup purposes and overflow it to disk to free up memory without completely removing the data from your cache.

-   **[Eviction](../developing/eviction/chapter_overview.html)**

    Use eviction to control data region size. Eviction actions are triggered by space-based thresholds.

-   **[Expiration](../developing/expiration/chapter_overview.html)**

    Use expiration to keep data current and to reduce region size by removing stale entries. Expiration actions are triggered by time-based thresholds.

-   **[Keeping the Cache in Sync with Outside Data Sources](../developing/outside_data_sources/sync_outside_data.html)**

    Keep your distributed cache in sync with an outside data source by programming and installing application plug-ins for your region.