pm2 running at 100% CPU - how to debug

Last couple of weeks, I am struggling with pm2 100% CPU usage which hangs my node server.

I tried reading logs but I didn't find any issue there.

My node version: 6.9.1
PM2 is : 2.4.4.
OS: Ubuntu 14.04
On an average my cpu usage is : ~5

Manually I am restarting all apps - pm2 restart all.

pm2.log: fluid_admin@instance-2:~$ tail -15 .pm2/pm2.log

2017-04-12 09:55:30: Starting execution sequence in -fork mode- for app name:fluid-prod id:0
2017-04-12 09:55:30: App name:fluid-prod id:0 online
2017-04-14 13:53:21: Stopping app:fluid-prod id:0
2017-04-14 13:53:21: Stopping app:nedbserver id:1
2017-04-14 13:53:21: App [nedbserver] with id [1] and pid [32557], exited with code [0] via signal [SIGINT]
2017-04-14 13:53:21: pid=32574 msg=failed to kill - retrying in 100ms
2017-04-14 13:53:21: pid=32557 msg=process killed
2017-04-14 13:53:21: Starting execution sequence in -fork mode- for app name:nedbserver id:1
2017-04-14 13:53:21: App [fluid-prod] with id [0] and pid [32574], exited with code [0] via signal [SIGINT]
2017-04-14 13:53:21: App name:nedbserver id:1 online
2017-04-14 13:53:21: pid=32574 msg=process killed
2017-04-14 13:53:21: Starting execution sequence in -fork mode- for app name:fluid-prod id:0
2017-04-14 13:53:21: App name:fluid-prod id:0 online

App is running on GAE, OS is : Ubuntu 14.04.

My CPU usage when PM2 is high

I have moved from forever to pm2 6 months back. till recent time, it was working file but now I am frequently having this issue.

I don't know deal this problem. Can some one help me how to debug this issue.

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