6 instances and counting are listed on https://grafana-labs.wikimedia.org/dashboard/db/top-instances?orgId=1 as 100 % user CPU, seemingly for tools.jem processes (maybe jembot):
top - 16:34:23 up 95 days, 19:50, 1 user, load average: 4.01, 4.11, 4.12 %Cpu(s): 36.2 us, 0.4 sy, 0.0 ni, 63.3 id, 0.1 wa, 0.0 hi, 0.0 si, 0.0 st PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 14532 tools.j+ 20 0 373064 19424 8820 R 100.0 0.2 34036:27 php-cgi 14533 tools.j+ 20 0 371348 12708 3940 R 98.8 0.2 34034:45 php-cgi 14536 tools.j+ 20 0 371508 18384 9148 R 98.8 0.2 34034:48 php-cgi 14535 tools.j+ 20 0 372328 14824 6092 R 92.7 0.2 34035:35 php-cgi
Are those tasks doing something useful or are they just stuck?