Setting the sysctl parameter aio-max-nr value to 1048576

The Linux kernel provides the Asynchronous non-blocking I/O (AIO) feature that allows a process to initiate multiple I/O operations simultaneously without having to wait for any of them to complete. This helps boost performance for applications that are able to overlap processing and I/O.

The performance can be tuned using the /proc/sys/fs/aio-max-nr virtual file in the proc file system. The aio-max-nr parameter determines the maximum number of allowable concurrent requests.

Another parameter, /proc/sys/fs/aio-nr, provides the current system-wide number of asynchronous requests.

Veritas recommends that you set the aio-max-nr value to 1048576. This helps HyperScale to perform optimally, in an environment that involves heavy I/O workloads.

Perform the following steps on all HyperScale compute and data nodes:

  1. To set the aio-max-nr value, add the following line to the /etc/sysctl.conf file:

    fs.aio-max-nr = 1048576

  2. To activate the new setting, run the following command:

    # sysctl -p /etc/sysctl.conf