OpenCloudOS-Kernel/Documentation/ABI/testing/sysfs-driver-xen-blkback

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What: /sys/module/xen_blkback/parameters/max_buffer_pages
Date: March 2013
KernelVersion: 3.11
Contact: Roger Pau Monné <roger.pau@citrix.com>
Description:
Maximum number of free pages to keep in each block
backend buffer.
What: /sys/module/xen_blkback/parameters/max_persistent_grants
Date: March 2013
KernelVersion: 3.11
Contact: Roger Pau Monné <roger.pau@citrix.com>
Description:
Maximum number of grants to map persistently in
blkback. If the frontend tries to use more than
max_persistent_grants, the LRU kicks in and starts
removing 5% of max_persistent_grants every 100ms.
What: /sys/module/xen_blkback/parameters/persistent_grant_unused_seconds
Date: August 2018
KernelVersion: 4.19
Contact: Roger Pau Monné <roger.pau@citrix.com>
Description:
How long a persistent grant is allowed to remain
allocated without being in use. The time is in
seconds, 0 means indefinitely long.
The default is 60 seconds.
What: /sys/module/xen_blkback/parameters/buffer_squeeze_duration_ms
Date: December 2019
KernelVersion: 5.6
Contact: SeongJae Park <sjpark@amazon.de>
Description:
When memory pressure is reported to blkback this option
controls the duration in milliseconds that blkback will not
cache any page not backed by a grant mapping.
The default is 10ms.
What: /sys/module/xen_blkback/parameters/feature_persistent
Date: September 2020
KernelVersion: 5.10
Contact: SeongJae Park <sjpark@amazon.de>
Description:
Whether to enable the persistent grants feature or not. Note
that this option only takes effect on newly created backends.
The default is Y (enable).