Unexpected Windows bloat is due to bug, not by design

Lurking in the release notes for this month's Patch Tuesday preview is a fix for a world of storage pain being experienced by some unlucky Windows 11 users. At the end of June, Microsoft said: "This update improves disk space usage for the CapabilityAccessManager.db-wal file" to KB5095093, the preview for July's patch Tuesday. The fix addresses a problem in which the CapabilityAccessManager.db-wal file can keep growing, potentially consuming gigabytes of disk space instead of the expected megabytes. Spotted by WindowsLatest, the problem file is a temporary Write-Ahead Log rather than an actual database. The file is used by Windows' Capability Access Manager functionality, which tracks app capabilities and privacy-related access. It usually hovers around a few megabytes. However, there are reports of the file growing far beyond that, with examples hitting 500 GB for an unfortunate subset of users. The result is that storage on the volume mysteriously fills up, and it is difficult for users to work out what is happening because Windows tucks the file away as a system file. This means that seeing unusual file-size behavior is difficult unless a user is happy to wade in with third-party tools or poke around on the command line. Otherwise, the file is grouped with the other System files for which Microsoft said, "These system files help Windows run properly. Your PC won't work without them." Or with them, if you're affected by the file growth bug. For affected users, the fix is to install the preview or wait until patch Tuesday (assuming there is enough disk space to install it). Write Ahead Log files are used to temporarily store transactions before they are written to the main database file. In SQLite, they represent a useful performance gain and are transparent to most users. Yes, they might grow, but the potential ballooning of the file used by Windows' Capability Access Manager is not normal behavior. Then again, the ballooning (or bloating) of Windows has long been observed by users (to the point where one enterprising engineer demonstrated how low Notepad could go). As such, affected users might not have immediately noticed the storage consumption, or put it down to Windows just doing its thing. (R)