| What: /sys/class/bdi/<bdi>/ |
| Date: January 2008 |
| Contact: Peter Zijlstra <a.p.zijlstra@chello.nl> |
| Description: |
| |
| Provide a place in sysfs for the backing_dev_info object. |
| This allows us to see and set the various BDI specific variables. |
| |
| The <bdi> identifier can be either of the following: |
| |
| MAJOR:MINOR |
| |
| Device number for block devices, or value of st_dev on |
| non-block filesystems which provide their own BDI, such as NFS |
| and FUSE. |
| |
| default |
| |
| The default backing dev, used for non-block device backed |
| filesystems which do not provide their own BDI. |
| |
| Files under /sys/class/bdi/<bdi>/ |
| --------------------------------- |
| |
| read_ahead_kb (read-write) |
| |
| Size of the read-ahead window in kilobytes |
| |
| reclaimable_kb (read-only) |
| |
| Reclaimable (dirty or unstable) memory destined for writeback |
| to this device |
| |
| writeback_kb (read-only) |
| |
| Memory currently under writeback to this device |
| |
| dirty_kb (read-only) |
| |
| Global threshold for reclaimable + writeback memory |
| |
| bdi_dirty_kb (read-only) |
| |
| Current threshold on this BDI for reclaimable + writeback |
| memory |
| |
| min_ratio (read-write) |
| |
| Minimal percentage of global dirty threshold allocated to this |
| bdi. If the value written to this file would make the the sum |
| of all min_ratio values exceed 100, then EINVAL is returned. |
| The default is zero |