The Graceful Apache restart is attempted by the server because of log file rotation on the server and it caused the server performance. To resolve the “log file rotation” server load issue enable the Piped Log feature from the WHM.Login in to the WHM as a root user and follow the following steps.
1. Login to WHM
2. Click /Service Configuration/
3. Click /Apache Configuration/
4. Click /Piped Log Configuration/
5. Check the box labeled /Enable piped Apache logs/
6. Click the Save button
For further explanation about “Piped Log feature” refer the following URL