System file cache (LargeSystemCache)
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Recommendation
Leave disabledLeave it disabled, as in the default client configuration.
Enabling it is only relevant for a temporary file server with a slow HDD: the cache claims a large share of memory and can evict applications.
- Scope
- System file cache
- FPS and memory
- FPS is not affected
What changes
Section titled “What changes”LargeSystemCache is a memory manager parameter. In the default client state, the system file cache grows as free memory is available, but does not claim it aggressively. When enabled, the cache claims a much larger share of RAM and can evict application memory: the game will have less available memory.
According to the visible BoosterX description, the effect is more noticeable on an HDD — repeated reads and copying of large files speed up; on an SSD the difference is small or absent.
Exceptions and differences
Section titled “Exceptions and differences”Why the checkbox is under “Legacy”: the policy is a server one — historically intended for file servers, not client Windows. According to the visible BoosterX description, starting with Windows 10 the parameter is obsolete: the file system already balances the cache dynamically, and enabling it can “eat” tens of gigabytes of RAM without a tangible gain. There is only one scenario of benefit: the PC temporarily works as a file server with a slow HDD.
How to verify the result
Section titled “How to verify the result”- Open Task Manager (Ctrl + Shift + Esc) → “Performance” → “Memory” and note the “Cached data”.
- Enable the setting, reboot, work with files and repeat the check: the cache should grow more noticeably, and free memory should decrease.
- If free memory has dropped without benefit for your scenarios, return it to the disabled state.
How to change and revert
Section titled “How to change and revert”In BoosterX, open “Optimization” → “Legacy” → “LargeSystemCache” (the item in the application list is named by the key without translation) and switch the toggle to “Disabled”: BoosterX will apply the enabling of the server cache policy. To revert, switch the toggle to “Enabled”: BoosterX will delete the value and return the default client state. Click “Apply” at the bottom of the page. If “Instant apply” is enabled, a separate click is not required. Reboot and check the “Cached data”.
Confirmation
Section titled “Confirmation”- Memory Manager research — why free RAM and cache should not be considered lost memory.
- Microsoft: Cache Manager — the architecture of the system cache.
Last check: 2026-09-20.