Since the move to the new real time OS based on CentOS7, Linux 4.9.80 and Rtai 5.1, we observe jumps of 2 to 7µs in the TolmProcessor elapsed time, approximatively every 5 minutes. Looking at the logs, there is a match between these jumps and a disconnection from the ganglia server.

```
rtpc7 (SIB2_Tpro)

Jan 22 00:02:43 rtpc7.virgo.infn.it sshd[20579]: Connection closed by 90.147.138.128 port 57010 [preauth]
Jan 22 00:07:43 rtpc7.virgo.infn.it sshd[20598]: Connection closed by 90.147.138.128 port 59364 [preauth]
Jan 22 00:12:43 rtpc7.virgo.infn.it sshd[20628]: Connection closed by 90.147.138.128 port 33470 [preauth]
Jan 22 00:17:43 rtpc7.virgo.infn.it sshd[20647]: Connection closed by 90.147.138.128 port 35826 [preauth]
Jan 22 00:22:43 rtpc7.virgo.infn.it sshd[20677]: Connection closed by 90.147.138.128 port 38168 [preauth]
Jan 22 00:27:43 rtpc7.virgo.infn.it sshd[20696]: Connection closed by 90.147.138.128 port 40516 [preauth]
Jan 22 00:32:43 rtpc7.virgo.infn.it sshd[20725]: Connection closed by 90.147.138.128 port 42888 [preauth]

rtpc6 (SPRB_Tpro)

Jan 22 00:02:03 rtpc6.virgo.infn.it sshd[29051]: Connection closed by 90.147.138.128 port 59064 [preauth]
Jan 22 00:07:03 rtpc6.virgo.infn.it sshd[29070]: Connection closed by 90.147.138.128 port 33188 [preauth]
Jan 22 00:12:03 rtpc6.virgo.infn.it sshd[29099]: Connection closed by 90.147.138.128 port 35552 [preauth]
Jan 22 00:17:03 rtpc6.virgo.infn.it sshd[29119]: Connection closed by 90.147.138.128 port 37908 [preauth]
Jan 22 00:22:03 rtpc6.virgo.infn.it sshd[29148]: Connection closed by 90.147.138.128 port 40252 [preauth]
Jan 22 00:27:03 rtpc6.virgo.infn.it sshd[29167]: Connection closed by 90.147.138.128 port 42604 [preauth]
```

There is probably some disk/network activities initiated by the the ganglia process that impacts the interrupt real time latency. To be investigated.