| 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. |
