On 07/28/2017 02:34 PM, Waiman Long wrote: > v2->v3: > - Add a faster pruning rate when the free pool is closed to depletion. > - As suggested by James Bottomley, add an artificial delay waiting > loop before killing a negative dentry and properly clear the > DCACHE_KILL_NEGATIVE flag if killing doesn't happen. > - Add a new patch to track number of negative dentries that are > forcifully killed. > > v1->v2: > - Move the new nr_negative field to the end of dentry_stat_t structure > as suggested by Matthew Wilcox. > - With the help of Miklos Szeredi, fix incorrect locking order in > dentry_kill() by using lock_parent() instead of locking the parent's > d_lock directly. > - Correctly account for positive to negative dentry transitions. > - Automatic pruning of negative dentries will now ignore the reference > bit in negative dentries but not the regular shrinking. > > A rogue application can potentially create a large number of negative > dentries in the system consuming most of the memory available. This > can impact performance of other applications running on the system. > > This patchset introduces changes to the dcache subsystem to limit > the number of negative dentries allowed to be created thus limiting > the amount of memory that can be consumed by negative dentries. > > Patch 1 tracks the number of negative dentries used and disallow > the creation of more when the limit is reached. > > Patch 2 enables /proc/sys/fs/dentry-state to report the number of > negative dentries in the system. > > Patch 3 enables automatic pruning of negative dentries when it is > close to the limit so that we won't end up killing recently used > negative dentries. > > Patch 4 prevents racing between negative dentry pruning and umount > operation. > > Patch 5 shows the number of forced negative dentry killings in > /proc/sys/fs/dentry-state. End users can then tune the neg_dentry_pc= > kernel boot parameter if they want to reduce forced negative dentry > killings. > > Waiman Long (5): > fs/dcache: Limit numbers of negative dentries > fs/dcache: Report negative dentry number in dentry-state > fs/dcache: Enable automatic pruning of negative dentries > fs/dcache: Protect negative dentry pruning from racing with umount > fs/dcache: Track count of negative dentries forcibly killed > > Documentation/admin-guide/kernel-parameters.txt | 7 + > fs/dcache.c | 451 ++++++++++++++++++++++-- > include/linux/dcache.h | 8 +- > include/linux/list_lru.h | 1 + > mm/list_lru.c | 4 +- > 5 files changed, 435 insertions(+), 36 deletions(-) > I haven't received any comment on this v3 patch for over 2 weeks. Is there anything I can do to make it more ready to be merged? Thanks, Longman -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
