红帽全球峰会第 4 章 Trim options on an LVM-VDO volume
LVM-VDO volumes offer two trim options. discard, which performs online block discard to automatically free unused blocks (use mount -o discard for immediate effect), and fstrim, which does periodic discards that require the admin to schedule and monitor the process.
注意
It is currently recommended to use fstrim application to discard unused blocks rather than the discard mount option because the performance impact of this option can be quite severe. For this reason, nodiscard is the default.
4.1. Enabling discard mount option on an LVM-VDO volume
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You can enable the discard option on your LVM-VDO volume.
Prerequisites
- An LVM-VDO volume exists on your system.
Procedure
Enable the
discardoption on your volume:# mount -o discard /dev/<vg_name>/<vdo_name> <mount_point>
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