PHP max exec timeout in [...]/dashboard/classes/Netmon.class.php if Dashboard left open for a too long

core 14.0.25.4
dashboard 14.0.6.2
framework 14.0.11

If you leave the Dashboard page up for hours at a time (Chrome Browser, not that it should matter), eventually the dreaded PHP max exec timeout happens in Dashboard's Netmon, completely locking up the GUI (including UCP). It takes pkill-ing all httpd processes and restarting the service to get the GUI back. Even with full apache debug, the only message generated indicating any issue is:

PHP Fatal error: Maximum execution time of 30 seconds exceeded in /var/www/html/admin/modules/dashboard/classes/Netmon.class.php on line 22, referer: http://###.###.###.##/admin/config.php?display=index

Otherwise, surrounding messages look clean:

[Mon May 06 00:39:26.339643 2019] [authz_core:debug] [pid 3037] mod_authz_core.c(809): [client ##.##.###.###:53120] AH01626: authorization result of Require all granted: granted
[Mon May 06 00:39:26.339650 2019] [authz_core:debug] [pid 3037] mod_authz_core.c(809): [client ##.##.###.###:53120] AH01626: authorization result of <RequireAny>: granted
[Mon May 06 00:39:26.339688 2019] [authz_core:debug] [pid 3037] mod_authz_core.c(809): [client ##.##.###.###:53120] AH01626: authorization result of Require all granted: granted
[Mon May 06 00:39:26.339695 2019] [authz_core:debug] [pid 3037] mod_authz_core.c(809): [client ##.##.###.###:53120] AH01626: authorization result of <RequireAny>: granted
[Mon May 06 00:40:26.808132 2019] [authz_core:debug] [pid 3034] mod_authz_core.c(809): [client ###.###.##.###:60215] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:40:26.808200 2019] [authz_core:debug] [pid 3034] mod_authz_core.c(809): [client ###.###.##.###:60215] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:42:38.807330 2019] [authz_core:debug] [pid 3035] mod_authz_core.c(809): [client ###.###.##.###:61124] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:42:38.807397 2019] [authz_core:debug] [pid 3035] mod_authz_core.c(809): [client ###.###.##.###:61124] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:44:49.808198 2019] [authz_core:debug] [pid 4385] mod_authz_core.c(809): [client ###.###.##.###:62197] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:44:49.808266 2019] [authz_core:debug] [pid 4385] mod_authz_core.c(809): [client ###.###.##.###:62197] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:47:04.807612 2019] [authz_core:debug] [pid 7512] mod_authz_core.c(809): [client ###.###.##.###:63369] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:47:04.807674 2019] [authz_core:debug] [pid 7512] mod_authz_core.c(809): [client ###.###.##.###:63369] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:48:07.475330 2019] [:error] [pid 3036] [client ###.###.##.###:61187] PHP Fatal error:  Maximum execution time of 30 seconds exceeded in /var/www/html/admin/modules/dashboard/classes/Netmon.class.php on line 22, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:48:08.525487 2019] [authz_core:debug] [pid 3036] mod_authz_core.c(809): [client ###.###.##.###:61187] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:48:08.525525 2019] [authz_core:debug] [pid 3036] mod_authz_core.c(809): [client ###.###.##.###:61187] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:49:16.809639 2019] [authz_core:debug] [pid 7515] mod_authz_core.c(809): [client ###.###.##.###:64194] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:49:16.809708 2019] [authz_core:debug] [pid 7515] mod_authz_core.c(809): [client ###.###.##.###:64194] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:51:48.809707 2019] [authz_core:debug] [pid 7517] mod_authz_core.c(809): [client ###.###.##.###:65378] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:51:48.809769 2019] [authz_core:debug] [pid 7517] mod_authz_core.c(809): [client ###.###.##.###:65378] AH01626: authorization result of <RequireAny>: granted, referer: http://###.###.###.##/admin/config.php?display=index
[Mon May 06 00:54:00.810726 2019] [authz_core:debug] [pid 7516] mod_authz_core.c(809): [client ###.###.##.###:50024] AH01626: authorization result of Require all granted: granted, referer: http://###.###.###.##/admin/config.php?display=index

I have ensured all modules are up to date as of this submission and have freshly rebooted the server. I have reliably "allowed it" to happen 3 times now over the course of about 12 hours...so it only takes about 4 hours of the Dashboard page sitting idle before it happens.