| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Backport of http://review.gluster.org/10770
Backport of http://review.gluster.org/10806
Backport of http://review.gluster.org/10787
Backport of http://review.gluster.org/10868
Backport of http://review.gluster.com/10852
- When a blocking lock is requested, lock request is succeeded even when
ec->fragment number of locks are acquired successfully in non-blocking locking
phase. This will lead to fop succeeding only on the bricks where the locks are
acquired, leading to the necessity of self-heals. To prevent these un-necessary
self-heals, if the remaining locks fail with EAGAIN in non-blocking lock phase
try blocking locking phase instead.
- Handle lookup failures while op in progress
- cluster/ec: Correctly cleanup delayed locks
When a delayed lock is pending, a graph switch doesn't correctly
terminate it. This means that the update of version and size xattrs
is lost, causing EIO errors. This patch handles GF_EVENT_PARENT_DOWN
event to correctly finish pending udpdates before completing the
graph switch.
- Fix use after free crash
ec_heal creates ec_fop_data but doesn't run ec_manager. ec_fop_data_allocate
adds this fop to ec->pending_fops, because ec_manager is not run on this heal
fop it is never removed from ec->pending_fops. When it is accessed after free
it leads to crash. It is better to not to add HEAL fops to ec->pending_fops
because we don't want graph switch to hang the mount because of a BIG
file/directory heal.
- Forced unlock when lock contention is detected
EC uses an eager lock mechanism to optimize multiple read/write
requests on the same entry or inode. This increases performance
but can have adverse results when other clients try to access the
same entry/inode. To solve this, this patch adds a functionality
to detect when this happens and force an earlier release to not
block other clients.
The method consists on requesting GF_GLUSTERFS_INODELK_COUNT and
GF_GLUSTERFS_ENTRYLK_COUNT for all fops that take a lock. When this
count is greater than one, the lock is marked to be released. All
fops already waiting for this lock will be executed normally before
releasing the lock, but new requests that also require it will be
blocked and restarted after the lock has been released and reacquired
again.
Another problem was that some operations did correctly lock the
parent of an entry when needed, but got the size and version xattrs
from the entry instead of the parent.
This patch solves this problem by binding all queries of size and
version to each lock and replacing all entrylk calls by inodelk ones
to remove concurrent updates on directory metadata. This also allows
rename to correctly update source and destination directories.
BUG: 1225279
Change-Id: I02a6084b138dd38e018a462347cd9ce38610c7ef
Reviewed-on: http://review.gluster.org/10926
Tested-by: NetBSD Build System
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Problem: Doing an 'ls' of a directory that has been modified while one
of the bricks was down, sometimes returns the old directory
contents.
Cause: Directories are not marked when they are modified as files are.
The ec xlator balances requests amongst available and healthy
bricks. Since there is no way to detect that a directory is
out of date in one of the bricks, it is used from time to time
to return the directory contents.
Solution: Basically the solution consists in use versioning information
also for directories, however some additional changes have
been necessary.
Changes:
* Use directory versioning:
This required to lock full directory instead of a single entry for
all requests that add or remove entries from it. This is needed to
allow atomic version update. This affects the following fops:
create, mkdir, mknod, link, symlink, rename, unlink, rmdir
Another side effect is that opendir requires to do a previous
lookup to get versioning information and discard out of date
bricks for subsequent readdir(p) calls.
* Restrict directory self-heal:
Till now, when one discrepancy was found in lookup, a self-heal
was automatically started. This caused the versioning information
of a bad directory to be healed instantly, making the original
problem to reapear again.
To solve this, when a missing directory is detected in one or more
bricks on lookup or opendir fops, only a partial self-heal is
performed on it. A partial self-heal basically creates the
directory but does not restore any additional information.
This avoids that an 'ls' could repair the directory and cause the
problem to happen again. With this change, output of 'ls' is
always consistent. However, since the directory has been created
in the brick, this allows any other operation on it (create new
files, for example) to succeed on all bricks and not add additional
work to the self-heal process.
To force a self-heal of a directory, any other operation must be
done on it. For example a getxattr.
With these changes, the correct healing procedure that would avoid
inconsistent directory browsing consists on a post-order traversal
of directoriesi being healed. This way, the directory contents will
be healed before healing the directory itslef.
* Additional changes to fix self-heal errors
- Don't use fop->fd to decide between fd/loc.
open, opendir and create have an fd, but the correct data is in
loc.
- Fix incorrect management of bad bricks per inode/fd.
- Fix incorrect selection of fop's target bricks when there are bad
bricks involved.
- Improved ec_loc_parent() to always return a parent loc as
complete as possible.
Change-Id: Iaf3df174d7857da57d4a87b4a8740a7048b366ad
BUG: 1149726
Signed-off-by: Xavier Hernandez <xhernandez@datalab.es>
Reviewed-on: http://review.gluster.org/8916
Reviewed-by: Dan Lambright <dlambrig@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
|
