Home > Workload Solutions > SQL Server > Best Practices > AMD-Based SQL Server Best Practices on Dell PowerEdge R740 and PowerMax 2000 > Linux Best Practices > Performance Best Practices > Red Hat Enterprise Linux: Last Accessed Time (atime)
In this best practice the Linux OS was updated, not to record the access time on files.
Category | Operating System |
Product | Red Hat Enterprise Linux 8.3 |
Type of best practice | Performance Optimization |
Day and value | Day 3, Fine Tuning |
Overview
The Linux operating system tracks the last time a file was accessed, a timestamp referred to as atime. For example, when the Linux operating system reads data from a data file the access time is updated. Databases frequently access data files and updating the access time with each access represents an overhead on the operating system and storage system possibly impacting performance.
It is possible to specify no-access-time (noatime), meaning the Linux operating system will not update the access time for files. The goal of this best practice was to reduce associated overhead and increase efficiency by setting the operating system to noatime.
The results of this best practice showed no performance improvements.
Recommendation
Changing the operating system not to track last accessed time on database files showed no performance improvements for the following:
The last accessed time recommendation has been a long-standing best practice that might have more value in the past. Still this best practice might have a greater impact on other database systems than our OLTP tests. For this reason, we recommend the read-ahead best practice as a Day 3, Fine Tuning consideration.
Implementation Steps
To update the noatime mount option, navigate to /etc/fstab file. Within the file, update the entry for each device accessed by the SQL Server application.
An example of this on the backup, data1 and data2 devices is shown below:
References