ONTAP 9 Manuals ( CA08871-402 )

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Enable and disable aggressive read-ahead mode

Beginning with ONTAP 9.14.1, you can enable and disable aggressive read-ahead mode on volumes in FabricPools that provide support for media and entertainment, such as movie streaming workloads. Aggressive read-ahead mode is available in ONTAP 9.14.1 on all on-premises platforms that support FabricPool. The feature is disabled by default.

About this task

The aggressive-readahead-mode command has two options:

  • none: read-ahead is disabled.

  • file_prefetch: the system reads the entire file into memory ahead of the client application.

Before you begin
  • You should be a cluster or SVM administrator.

  • You must be at the advanced privilege level.

Enable aggressive read-ahead mode during volume creation

Steps
  1. Set the privilege level to advanced:

    set -privilege advanced
  2. Create a volume and enable aggressive read-ahead mode:

    volume create -volume <volume name>  -aggressive-readahead-mode <none|file_prefetch>

    The following example creates a volume named vol1 with aggressive read-ahead enabled with the file_prefetch option:

    volume create -volume vol1 -aggressive-readahead-mode file_prefetch

Disable aggressive read-ahead mode

Steps
  1. Set the privilege level to advanced:

    set -privilege advanced
  2. Disable aggressive read-ahead mode:

    volume modify -volume <volume name>  -aggressive-readahead-mode none

    The following example modifies a volume named vol1 to disable aggressive read-ahead mode:

    volume modify -volume vol1 -aggressive-readahead-mode none

View aggressive read-ahead mode on a volume

Steps
  1. Set the privilege level to advanced:

    set -privilege advanced
  2. View the aggressive read-ahead mode:

    volume show -fields aggressive-readahead-mode
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