High memory footprint after long uptime: heap breakdown & source code locations

[sususu98]

Summary

After long continuous uptime, Hidden Bar's memory footprint in Activity Monitor can grow to 600MB+. Diagnostic tools (footprint & heap) reveal that while active Resident Memory (RSS) remains small (~50MB), the process accumulates ~190k malloc nodes and ~500MB of swapped/compressed dirty pages.

Diagnostic Findings (footprint & heap)

• Total Malloc Nodes: ~193,000 nodes (MALLOC_SMALL count ~159,700)
• Top Allocated Types:
  • NSMutableDictionary / CFData: 6,000+ instances
  • __NSMallocBlock__: 3,200+ instances
  • CAContext._impl (QuartzCore layer contexts): 800+ instances

Corresponding Source Locations

1. StatusBarController.swift (lines 125-144) — setupHoverToExpandIfEnabled

   • High-frequency global mouse movement monitoring (NSEvent.addGlobalMonitorForEvents(matching: .mouseMoved)) accumulates NSMutableDictionary and CFData event wrapper instances over long runtimes.

2. StatusBarController.swift (lines 316-329) — startTimerToAutoHide

   • When deferring auto-collapse (e.g., when the mouse is in the menu bar), repeatedly invalidating and re-scheduling single-shot Timer instances creates new closure blocks, accumulating __NSMallocBlock__ and dispatch continuations.

3. Assets.swift (lines 13-26) & StatusBarController.swift (lines 270, 281)

   • Assets.expandImage / collapseImage are computed properties evaluating NSImage(named:) dynamically. Re-assigning button.image on expand/collapse actions repeatedly rebinds AppKit button layer contexts, accumulating CAContext._impl instances.

4. StatusBarController.swift (line 342) — getContextMenu

   • NotificationCenter.default.addObserver is invoked inside menu construction, which may add duplicate observers if the context menu is re-instantiated.

Hope this diagnostic breakdown helps!