In this best practice we implemented the Network Time Protocol (NTP). Implementing NTP enables multiple computer systems to synchronize time which can be critical for applications and their recovery.

Overview

The Network Time Protocol (NTP) is used to synchronize clocks between computer systems. NTP enabled servers have a common time reference enabling activities like analysis, audits, and performance tuning. This is not a performance best practice as the goal is to have all our database servers synchronized from the same NTP server. 

Recommendation

We did not expect significant performance changes upon implementing NTP. The performance metrics below showed no change when NTP was running on the database servers: 

• New Orders per Minute (NOPM) 
• Transactions per Minute (TPM) 
• PowerMax IOPS
• Server CPU utilization
• DB File Sequential Read 
• Log File Parallel Write 

Implementation Steps

In RHEL8, the NTP protocol is implemented by the chrony daemon through the chrony package

Use the following steps to configure the daemon:

1. Install the chrony patckage if it is not installed: #yum  install chrony
2. Edit /etc/chrony.conf file by adding k.
3. To start chronyd:  # systemctl start chronyd
4. To stop chronyd:  # systemctl stop chronyd
5. To ensure chrondy starts automatically at system start, # systemctl enable  chronyd
6. To check if chrony is synchronized :$chronyc tracking
7. To check chrony source: #chronyc sources
8. To check chrony source statistics:  #chronyc sourcestats

Additional Resources

Red Hat Product Documentation: Configuring basic system settings