bc88866657
The goal of this function is to evict enough meta data buffers from the ARC in order to enforce the arc_meta_limit. Achieving this is slightly more complicated than it appears because it is common for data buffers to have holds on meta data buffers. In addition, dnode meta data buffers will be held by the dnodes in the block preventing them from being freed. This means we can't simply traverse the ARC and expect to always find enough unheld meta data buffer to release. Therefore, this function has been updated to make alternating passes over the ARC releasing data buffers and then newly unheld meta data buffers. This ensures forward progress is maintained and arc_meta_used will decrease. Normally this is sufficient, but if required the ARC will call the registered prune callbacks causing dentry and inodes to be dropped from the VFS cache. This will make dnode meta data buffers available for reclaim. The number of total restarts in limited by zfs_arc_meta_adjust_restarts to prevent spinning in the rare case where all meta data is pinned. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Pavel Snajdr <snajpa@snajpa.net> Issue #3160 |
||
---|---|---|
.. | ||
avl | ||
nvpair | ||
unicode | ||
zcommon | ||
zfs | ||
zpios | ||
.gitignore | ||
Makefile.in |