macOS daemon dasd hid 46GB memory leak from standard monitors, halting automation for a day

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A developer's automated social media posting system went silent for 24 hours on August 9, 2026, despite standard memory monitoring showing no anomalies. The culprit was dasd, a macOS background scheduling daemon, which had accumulated 46GB of compressed memory while displaying only 264MB of RSS — the metric most tools sort by. Because macOS compresses idle memory into RAM without reflecting it in RSS, the bloat remained invisible to conventional top commands and drove swap usage to 37GB, causing Playwright browser contexts to time out. The hidden leak was only revealed by adding the compressed-memory column via top's -stats option. A guard script set to run every 10 minutes was then deployed to detect and reclaim the leak automatically, restoring swap to 4.1GB overnight without manual intervention.

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