Wiping the cache partition is a common troubleshooting step for fixing performance issues or software bugs on Android devices. It clears out temporary system files and caches created by apps and the operating system. However, a cache wipe does not delete personal data like photos, videos, music, documents, text messages, call logs, contacts, apps, or system settings. The cache partition stores transient data that can be recreated, while important user information is stored in separate internal storage partitions that are unaffected by a cache wipe.
What is the cache partition?
Every Android device has a cache partition that stores temporary app data and system files that help speed up everyday performance. The cache acts as a buffer zone, keeping frequently accessed data readily available rather than having to load it from the main storage every single time. For example, thumbnails of photos, music artwork, pieces of apps that run in the background, browser cookies/history, GPS locations, and other types of system and app metadata will reside in the cache after initial access.
Caching this transient data makes processes quicker, however it can build up over time and lead to sluggish performance if not cleared periodically. The cache partition typically ranges from 150MB to over 1GB in size depending on how much temporary data is generated. Wiping this partition simply erases the contents to free up space and remove potentially corrupted files that could be slowing things down.
What gets deleted when wiping the cache partition?
A cache wipe essentially resets the cache back to an empty state. Here are some examples of data stored in the cache partition that will get deleted:
- App cache files and data
- Browser history, cookies, caches
- Dalvik cache compiled code
- Residual app files/data
- Temporary system files
- Cached media files like thumbnails and artwork
- Location and GPS data
- Log files
As you can see, the cache stores transient helper data that allows apps and system processes to function smoothly, but is not critical user content. Your apps, contacts, messages, photos, videos, music, downloads, and other key user data is stored in the separate internal storage partition. A cache wipe will not affect these items.
What does not get deleted during a cache wipe?
Here are some examples of user data that is stored outside of the cache partition and will remain intact after wiping the cache:
- Text messages
- Call logs
- Apps and settings
- Downloaded files
- Camera photos/videos
- App data
- WiFi passwords
- Home screen layout
- System settings
In essence, a cache partition wipe clears out the “junk” files while leaving your meaningful data untouched. The only consequence is that accessing certain data or apps may take slightly longer right after a wipe since the cache needs to rebuild itself.
When should you wipe the cache partition?
Here are some common instances when wiping the cache partition is recommended:
- You’re experiencing random application crashes, freezes, or buggy performance
- Your device feels very sluggish overall
- Apps are slower to launch and respond
- You start having issues after a major OS update
- You want to sell or give away your device and want to do a factory reset without fully erasing data
- Troubleshooting steps recommend a cache wipe
Since the cache buildup happens gradually, periodic cache wipes every few months can also help nip performance issues in the bud.
How to wipe the cache partition
Wiping the cache partition is simple and can be done right from your device:
- Power off your device completely
- Press and hold the Power button to turn it back on
- When the boot logo appears, press and hold the Volume Down button
- Select “Wipe cache partition” using the Volume keys
- Press Power button to select
- Allow your device to reboot
That’s all there is to it! The process should only take a minute or two. Some devices may have slightly different steps to enter recovery mode and access the wipe cache option.
Before and after cache wipe comparisons
To understand exactly what changes and what stays the same from a cache wipe, here are some before and after comparisons of common device data:
|Data Type||Before Wipe||After Wipe|
|Contacts list||Remains intact||No change, all contacts still available|
|Text messages||All messages available||Messages unaffected, none deleted|
|Call logs||Call history intact||Call logs remain unchanged|
|Photos/videos||All images/vids accessible||No photos or videos erased|
|Downloaded files||Downloads folder populated||No loss of downloaded content|
|Music files||Entire music library available||Music collection remains intact|
|WiFi passwords||All WiFi networks saved||No WiFi data removed|
|Apps||All apps installed||No apps deleted|
|App data||App data preserved||No app data wiped|
|System settings||All settings configured||Settings untouched|
As you can see, a cache wipe selectively removes temporary cached files while leaving all permanent user data intact.
App and system performance changes
While user data is not affected, app and system performance will be different after wiping the cache partition until it builds back up. Here are some examples:
- Apps may launch a bit slower at first
- Maps and GPS may need to re-cache location data
- Browser will need to re-index sites and re-download assets
- Rebooting may take longer
- Media thumbnails will need to be regenerated
- Some data like settings and logins may need re-caching
So expect some temporary slowdowns right after wiping. This is normal as the cache partition clears out and begins storing data again during usage. Within a day or two performance should be back to normal.
Wiping the cache partition can bring new life to a sluggish Android device by clearing out system clutter. It deletes temporary cached files while retaining all permanent user data and apps. Contacts, messages, call logs, photos, videos, music, downloads, and app data all persist unchanged. The only downside is slower performance temporarily until frequently used data is cached again. Overall, wiping cache is a safe and easy way to troubleshoot various Android issues with no permanent data loss.