glusterfs.git/xlators/cluster/afr/src/afr-dir-read.c, branch v3.7.0

cluster/afr: Make read child match check in afr optional

2015-03-18T09:29:22+00:00

Having this particular check which was introduced by
commit c78998c39f0857ea7aacba360632c148afc54a55 causes a drop in
performance in readdirp. So the behavior is made configurable with this
patch.

Change-Id: I2858fc18b3539df7aa6d3f489e0d5cfaeb8a9b3c
BUG: 1202669
Signed-off-by: Krutika Dhananjay 
Reviewed-on: http://review.gluster.org/9917
Tested-by: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Pranith Kumar Karampuri

cluster/afr: When parent and entry read subvols are different, set entry->inode to NULL

2015-02-02T20:07:08+00:00

That way a lookup would be forced on the entry, and its attributes will
always be selected from its read subvol.

Change-Id: Iaba25e2cd5f83e983fc8b1a1f48da3850808e6b8
BUG: 1179169
Signed-off-by: Krutika Dhananjay 
Reviewed-on: http://review.gluster.org/9477
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

afr: stop encoding subvolume id in readdir d_off

2014-12-26T14:21:44+00:00

The purpose of encoding d_off in AFR is to indicate the
selected subvolume for the first readdir, and continue all
further readdirs of the session on the same subvolume. This is
required because, unlike files, dir d_offs are specific to the
backend and cannot be re-used on another subvolume. The d_off
transformation encodes the subvolume id and prevents such
invalid use of d_offs on other servers.

However, this approach could be quite wasteful of precious d_off
bit-space. Unlike DHT, where server id can change from entry to
entry and thus encoding the server id in the transformed d_off
is necessary, we could take a slightly relaxed approach in AFR.
The approach is to save the subvolume where the last readdir
request was sent in the fd_ctx. This consumes constant space (i.e
no per-entry cache), and serves the purpose of avoiding d_off
"misuse" (i.e using d_off from one server on another).

The compromise here is NFS resuming readdir from a non-0 cookie
after an extended delay (either anonymous FD has been reclaimed,
or server has restarted). In such cases a subvolume is picked
freshly. To make this fresh picking more deterministic (i.e, to
pick the same subvolume whenever possible, even after reboots),
the function afr_hash_child (used by afr_read_subvol_select_by_policy)
is modified to skip all dynamic inputs (i.e PID) for the case
of directories.

Change-Id: I46ad95feaeb21fb811b7e8d772866a646330c9d8
BUG: 1163161
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/9332
Tested-by: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: Pranith Kumar Karampuri

cluster/afr: Fix dirent leak

2014-07-14T16:29:19+00:00

afr does itransform by taking the list of entries given by client xlator
to separate list but doesn't free that list.

Change-Id: Ibb4d38b4934b2bb924385c88f9d7942fad933cb9
BUG: 1117243
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/8261
Tested-by: Gluster Build System 
Reviewed-by: Krutika Dhananjay 
Reviewed-by: Ravishankar N

cluster/afr: refactor

2014-03-22T12:25:57+00:00

- Remove client side self-healing completely (opendir, openfd, lookup)
- Re-work readdir-failover to work reliably in case of NFS
- Remove unused/dead lock recovery code
- Consistently use xdata in both calls and callbacks in all FOPs
- Per-inode event generation, used to force inode ctx refresh
- Implement dirty flag support (in place of pending counts)
- Eliminate inode ctx structure, use read subvol bits + event_generation
- Implement inode ctx refreshing based on event generation
- Provide backward compatibility in transactions
- remove unused variables and functions
- make code more consistent in style and pattern
- regularize and clean up inode-write transaction code
- regularize and clean up dir-write transaction code
- regularize and clean up common FOPs
- reorganize transaction framework code
- skip setting xattrs in pending dict if nothing is pending
- re-write self-healing code using syncops
- re-write simpler self-heal-daemon

Change-Id: I1e4080c9796c8a2815c2dab4be3073f389d614a8
BUG: 1021686
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6010
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cluster/afr: skip directory inspection when entry self-heal is off

2013-08-11T18:13:02+00:00

When user has explicitly configured to disable entry self-heal in the
client, it is wrong to do the healing in opendir. So skip it. This
is especially useful to reduce opendir() times after graph switches.

Change-Id: Ic6eb9ff2334a5b8417f2f35410a366a536bad5df
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/5528
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cluster/afr: Unwind frame on error in readdir[p]

2013-08-09T04:05:06+00:00

Change-Id: I5701bf115e0aa1adb4fb52f5418534910a2268d4
BUG: 994959
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/5531
Reviewed-by: Vijay Bellur 
Tested-by: Gluster Build System

cluster/afr: Handle REPLICATE_TRASH_DIR from old bricks

2013-07-26T08:13:58+00:00

Change-Id: Ib99f79d3fa607c818dbc62006516480f598d8add
BUG: 886998
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4640
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cluster/afr: Remove strict-readdir implementation

2013-01-23T09:26:09+00:00

Leaving option frame-work un-changed for backward compatibility.

Change-Id: I40bce1ec360801307e67f09e53b0721f64efab37
BUG: 886998
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4309
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

cluster/afr: Provide option to disable readdir failover

2012-12-03T08:11:02+00:00

In a replica pair unlike files, directories may not have their
content in same order, so readdir for same (offset, size) may
not give same entries on both the sobvolumes of replica pair.
Switching over from one subvolume to another may not be a good
idea sometimes. It may lead to duplicate entries or fewer entries
or both. This patch provides a way to disable readdir-failover
so that applications like rebalance can retry if they want to.

Change-Id: I2b23eb224a2e84016a561362932613ac824c11a0
BUG: 859387
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4159
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur