This issue is caused by Open-VM tools running on NSX Edge that can cause high memory usage due to memory leak
Eventually NSX Edge becomes unmanageable and reboots automatically as a part of auto-recovery.
Sometime Edge needs to be be manually rebooted to clear high memory usage if an automatic reboot doesn't occur.
Verify this issue by below: (Log snippets vary from NSX Edge to Edge/Version to Version)
1. Critical Alarms shown in UI (NSX Edge is out of memory. The Edge is rebooting in 3 seconds. Top 5 processes are: {#}.)
2. Check NSX Edge logs and verify memory usage warnings
2020-06-06T05:22:55+00:00 NSX Edge MsgMgr[1778]: [default]: [daemon.info] payload len:368 data:{"systemEvents":[{"moduleName":"vShield Edge Appliance","severity":"Critical","eventCode":"30149","message":"vShield Edge memory over used","timestamp":1591420975,"metaData":{"message":"Memory usage: 90.05%","details":" 1772 390456 987680 vmtoolsd 801 4156 200708 syslog-ng 7652 3716 67060 sync_path.pl 7406 2808 14144 sh 7382 2752 14140 runevery.sh "}}]
2020-06-06T05:26:18+00:00 NSX Edge kernel[]: [default]: [kern.warning] dcsms invoked oom-killer: gfp_mask=0x24201ca, order=0, oom_score_adj=0
2020-06-06T05:26:18+00:00 NSX Edge kernel[]: [default]: [kern.err] Out of memory: Kill process 1772 (vmtoolsd) score 817 or sacrifice child
2020-06-06T05:26:18+00:00 NSX Edge kernel[]: [default]: [kern.err] Killed process 1772 (vmtoolsd) total-vm:987756kB, anon-rss:384548kB, file-rss:244kB
2020-06-06T05:26:18+00:00 NSX Edge OOMChecker[1780]: [default]: [daemon.warning] OOM, top 5 memory used processes: 8347 54180 116972 VseEventProcess 801 3824 200708 syslog-ng 8349 2780 14144 sh 1780 2628 39876 VseOOMChecker.p 7652 2548 67060 sync_path.pl
2020-06-06T05:26:18+00:00 NSX Edge config[]: [default]: [daemon.info] INFO :: Utils :: ha: UpdateHaResourceFlags:
2020-06-06T05:26:18+00:00 NSX Edge MsgMgr[1778]: [default]: [daemon.info] Building event message
2020-06-06T05:26:18+00:00 NSX Edge MsgMgr[1778]: [default]: [daemon.info] correlation id:Event_502a1cba-7f73-2be8-49a6-5b96ce953aaf1591421178
2020-06-06T05:26:18+00:00 NSX Edge MsgMgr[1778]: [default]: [daemon.info] payload len:360 data:{"systemEvents":[{"severity":"Critical","message":"OOM happened, system rebooting in 3 seconds...","metaData":{"message":" 8347 54180 116972 VseEventProcess 801 3824 200708 syslog-ng 8349 2780 14144 sh 1780 2628 39876 VseOOMChecker.p 7652 2548 67060 sync_path.pl "},"timestamp":1591421178,"eventCode":30180,"moduleName":"vShield Edge Appliance"}]}
2020-06-06T05:26:21+00:00 NSX Edge shutdown[8425]: [default]: [user.notice] shutting down for system reboot
vsm.log
2020-06-06 13:28:18.992 XXX INFO SimpleAsyncTaskExecutor-1 EventServiceImpl:119 - - [nsxv@6876 comp="nsx-manager" subcomp="manager"] [SystemEvent] Time:'Sat Jun 06 13:27:21.000 xxx 2020', Severity:'Informational', Event Source:'edge-xxxxxxxx-xxxxxxxxx-xxxx-xxxxxxxxxxxx', Code:'30101', Event Message:'NSX Edge was booted', Module:'vShield Edge Appliance', Universal Object:'false
Edge System Process via TOP command
USER PID PPID %CPU %MEM VSZ RSS NI TTY STAT STIME TIME COMMAND
root 1175 1147 0.0 67.3 943376 335868 0 ? Sl 2018 07:05:47 /usr/local/bin/vmtoolsd --plugin-path=/usr/local/lib/open-vm-tools/plugins/vmsvc/