fix(gateway): set NumberOfFiles limits in macOS launchd plist (#36899) - #36939
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fix(gateway): set NumberOfFiles limits in macOS launchd plist (#36899)#36939luyao618 wants to merge 1 commit into
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…search#36899) The generated LaunchAgent plist did not include SoftResourceLimits or HardResourceLimits entries. Under launchd, gateway processes inherit a default RLIMIT_NOFILE soft limit (typically 256), which the long-running gateway exhausts over time. This surfaces as: OSError: [Errno 24] Too many open files: '/Users/<user>/.hermes/sessions/.sessions_<random>.tmp' during atomic writes of sessions.json (and other paths). Add SoftResourceLimits and HardResourceLimits dicts with NumberOfFiles=65536 to generate_launchd_plist() so newly installed LaunchAgents get a sane fd budget out of the box. Existing gateway installs will pick up the new limits on the next 'hermes gateway install' (plist-current check will detect drift and rewrite). Adds a regression test that asserts both keys + the NumberOfFiles integer are present in the emitted plist.
alt-glitch
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type/bug
This was referenced Jun 7, 2026
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Summary
Fixes #36899.
On macOS, gateway installs as a launchd LaunchAgent inherit a default
RLIMIT_NOFILEsoft limit (typically 256). Long-running gateway processes eventually exhaust that budget and crash during atomic writes ofsessions.jsonwith:The generated plist in
hermes_cli/gateway.py::generate_launchd_plist()previously did not set any resource limits, so launchd's default applied.Fix
Embed
SoftResourceLimitsandHardResourceLimitsdicts withNumberOfFiles=65536in the emitted plist. This matches the verified manual workaround in the issue and is well below macOS's hard ceiling, so it lifts the soft limit without requiring any user intervention. The existinglaunchd_plist_is_current()drift check will rewrite stale plists on the nexthermes gateway install --system.Verification
python -m pytest tests/hermes_cli/test_gateway_service.py -k launchd_plist— passes.test_launchd_plist_sets_nofiles_resource_limitsparses the generated plist and asserts both keys +NumberOfFilesintegers are present (verified at 65536 viaplistlib.loads).NumberOfFilesis a documented launchd key (seeman launchd.plist), no regressions.Scope
hermes_cli/gateway.py—generate_launchd_plist()(XML insertion only)tests/hermes_cli/test_gateway_service.py— one focused regression test