Does LockDown Browser Have a Memory Leak on Mac? (2026 Investigation)

Last updated 2026-05-02 · LDBypass Editorial

Measured memory growth (LDBypass benchmark)

From a 3-hour mock exam reproduction, LDB resident memory sampled at 30-second intervals:

Pattern: ~5-15% growth across all configurations.

Is this a leak?

"Memory leak" in the strict programming sense means memory allocated but never freed. From the public observable behavior:

• Growth is bounded - peaks plateau after ~2 hours.
• Growth correlates with Monitor recording duration - longer exams + recording = more growth.
• Memory drops back to baseline ~2-3 minutes after submit + LDB exit.
• No process restart needed to reclaim memory after exam.

This pattern is consistent with a buffer that grows during recording but releases on exam end - not a leak. Monitor encodes video in chunks; the encode buffer + retransmit-on-failure queue hold ~50-200 MB during active recording.

Why this matters on 8 GB Macs

The 5-15% growth at 8 GB combined with macOS's already-tight memory budget is what tips 8 GB Macs into swap or OOM during long exams. From RAM usage page: 8 GB Air OOM-killed in 2/3 reproductions at the 73-minute mark.

For 16 GB+ Macs, the growth is invisible - there's plenty of headroom.

How to verify on your own Mac

1. Open Activity Monitor before launching LDB.
2. Search for "LockDown Browser" in Activity Monitor (LDB will appear once launched).
3. Note the "Memory" column value at launch.
4. Run your practice exam.
5. Check Memory column at 30-min intervals.
6. Note the value at submit.
7. After LDB exits, confirm Memory drops back to baseline (LDB process ends entirely, so this is moot - comparing to a fresh LDB launch).

If you suspect a real leak (not Monitor buffer)

Symptoms of an actual leak vs. expected buffer growth:

• Buffer growth (expected): linear with recording time; plateaus; releases on exam end.
• Real leak (bug): growth doesn't plateau; continues at compounded rate; survives exam end.

If you observe the second pattern reproducibly, save Activity Monitor screenshots at 30-min intervals + the most recent diagnostic report from ~/Library/Logs/DiagnosticReports/, and report to Respondus support.

Reproducing on your hardware

To compare against our measurements:

1. Charge to 100%, plug out.
2. Quit every app except Activity Monitor.
3. Run a 90-min mock exam from your university's practice exam.
4. Sample LDB Memory column at exam start, 30 min in, 60 min in, exam end.
5. Compare to our values for your specific Mac configuration.

If your numbers are wildly different, your environment has a confounding factor (AV, cloud sync, lots of background processes) that we eliminated.

Mitigations during long exams

1. Plug in for any exam > 90 min. macOS's memory management is more aggressive on AC power; less swap pressure.
2. Quit other apps aggressively before launch. Other apps' resident memory directly competes with LDB's buffer.
3. For 8 GB Macs: see the comprehensive mitigations in RAM usage page. Honestly, borrow a 16 GB Mac if possible.