[PATCH v5 00/10] speculative preallocation inode tracking

Brian Foster
2012-10-05T14:53:07Z

Hi all,

This is v3 of the speculative preallocation inode tracking patchset. This
functionality tracks inodes with post-EOF speculative preallocation for the
purpose of background and on-demand trimming.

Background scanning occurs on a longish interval (5 minutes by default) and in
a best-effort mode (i.e., inodes are skipped due to lock contention or dirty
cache). The intent is to clear up post-EOF blocks on inodes that might have
allocations hanging around due to open-write-close sequences (NFS).

On demand scanning is provided via a new ioctl and supports various parameters
such as scan mode, filtering by quota id and minimum file size. A pending use
case for on demand scanning is for accurate quota accounting via the gluster
scale out filesystem (i.e., to free up preallocated space when near a usage
limit).

Brian

v5:
- Rebased against the die-xfssyncd-die patchset.
- Renamed xfs_inodes_free_eofblocks() to xfs_icache_free_eofblocks().
- Migrated xfs_can_free_eofblocks() from static inline to xfs_inode.c.
- Fixed xfs_eofblocks version field and added version check to ioctl().
- Reworked quota filtering to use standard quota fields. Added patch 7 to
support.
- Split min. file size filtering into a separate patch.
- Reworked background scanning based on rebase. Created a new eofblocks
workqueue, renamed the tunable and based its value in seconds.

v4:
- Fix the broken need_iolock parameter to the xfs_free_eofblocks() call in
patch 5 (thanks to Ben M. for testing). This is a one line change. All
other patches equivalent to v3. This version survives an xfstests run (with
XFS_DEBUG enabled this time :P).

v3:
- Pushed dirty cache check up into patch 5 (minor clean up).
- Reworked xfs_can_free_eofblocks() in patch 3 as per Dave C.'s review.
- Rebased from linus' tree to the XFS tree.

v2:
- Remove unnecessary inode flag clear helper.
- Condense eofblocks set/clear tag functions.
- Move clear tag call into xfs_free_eofblocks().
- Modify AG walk infrastructure to support tag-based walk and utilize this
functionality for the eofblocks scan (as opposed to the previous code
duplicated from reclaim scanning).
- Improve ioctl functionality: new data structure fields/flags, validate quota
is enabled.
- Increase default background scanning interval to 5 minutes, add tunable.

Brian Foster (10):
xfs: add EOFBLOCKS inode tagging/untagging
xfs: support a tag-based inode_ag_iterator
xfs: create helper to check whether to free eofblocks on inode
xfs: make xfs_free_eofblocks() non-static, return EAGAIN on trylock
failure
xfs: create function to scan and clear EOFBLOCKS inodes
xfs: add XFS_IOC_FREE_EOFBLOCKS ioctl
xfs: make xfs_quota_type() non-static
xfs: add quota id filtering to eofblocks scan
xfs: add minimum file size filtering to eofblocks scan
xfs: add background scanning to clear eofblocks inodes

fs/xfs/xfs_ag.h | 1 +
fs/xfs/xfs_fs.h | 20 ++++
fs/xfs/xfs_globals.c | 1 +
fs/xfs/xfs_icache.c | 220 ++++++++++++++++++++++++++++++++++++++++++++--
fs/xfs/xfs_icache.h | 12 ++-
fs/xfs/xfs_inode.c | 37 ++++++++
fs/xfs/xfs_inode.h | 1 +
fs/xfs/xfs_ioctl.c | 24 +++++
fs/xfs/xfs_iomap.c | 8 ++
fs/xfs/xfs_iops.c | 4 +
fs/xfs/xfs_linux.h | 1 +
fs/xfs/xfs_mount.c | 2 +
fs/xfs/xfs_mount.h | 3 +
fs/xfs/xfs_qm_syscalls.c | 5 +-
fs/xfs/xfs_quota.h | 1 +
fs/xfs/xfs_quotaops.c | 2 +-
fs/xfs/xfs_super.c | 9 ++
fs/xfs/xfs_sysctl.c | 9 ++
fs/xfs/xfs_sysctl.h | 1 +
fs/xfs/xfs_trace.h | 6 ++
fs/xfs/xfs_vnodeops.c | 27 +++---
fs/xfs/xfs_vnodeops.h | 1 +
22 files changed, 368 insertions(+), 27 deletions(-)

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1.7.7.6