diff options
author | Pranith Kumar K <pranithk@gluster.com> | 2012-04-14 14:33:53 +0530 |
---|---|---|
committer | Anand Avati <avati@redhat.com> | 2012-05-18 20:30:30 -0700 |
commit | fa90243e20eeef91eda5a5bb249bed05066852e3 (patch) | |
tree | 7add1693e67dc25e69b8c1f8ed6d6e096c84461f /xlators/cluster/afr/src/afr-transaction.h | |
parent | 24c1cbf4f7afd54a506a8265de9d22ce2b2e670f (diff) |
cluster/afr: Enforce order in pre/post op
The xattrop order in pre/post op on all the subvols
is client-0, client-1... client-n where n is (replica-count - 1).
This order can lead to invalid split-brains if the brick
dies in the middle of xattrops.
Example: transaction completed pre-op, so on all the subvolumes
xattrs have '1' changelog. Now post-op is sent to both the subvols.
On subvol-0 change-log of client-0 is decremented to 0, before
decrementing change-log of client-1 to 0 the brick dies.
This change-log status on subvol-0 gives the meaning that a
change is done on subvol-0 successfully but on subvol-1 it failed.
Which is not what happened.
Changes done when the subvol-0 was down will lead to pending
change-log on subvol-1 for subvol-0. Which is correct.
When the subvol-0 is brought back up, the change-log will be in
split-brain state even when it is not a legitimate split-brain.
If the brick dies in the middle of xattrops it should remain fool.
Pre-op should perform xattrop of the local change-log first and
post-op should perform xattrop of the local change-log last.
In case of optimistic changelogs txn_changelog should be done
last on local if it succeeds, first if it fails.
Change-Id: Ib6eeb20cdc49b0b1fd2f454f25a9c8e08388c6e7
BUG: 765194
Signed-off-by: Pranith Kumar K <pranithk@gluster.com>
Reviewed-on: http://review.gluster.com/3226
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>
Diffstat (limited to 'xlators/cluster/afr/src/afr-transaction.h')
-rw-r--r-- | xlators/cluster/afr/src/afr-transaction.h | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/xlators/cluster/afr/src/afr-transaction.h b/xlators/cluster/afr/src/afr-transaction.h index 965ee6737..d19d16fb3 100644 --- a/xlators/cluster/afr/src/afr-transaction.h +++ b/xlators/cluster/afr/src/afr-transaction.h @@ -11,6 +11,11 @@ #ifndef __TRANSACTION_H__ #define __TRANSACTION_H__ +typedef enum { + LOCAL_FIRST = 1, + LOCAL_LAST = 2 +} afr_xattrop_type_t; + void afr_transaction_fop_failed (call_frame_t *frame, xlator_t *this, int child_index); @@ -24,5 +29,6 @@ afr_transaction (call_frame_t *frame, xlator_t *this, afr_transaction_type type) afr_fd_ctx_t * afr_fd_ctx_get (fd_t *fd, xlator_t *this); int -afr_set_pending_dict (afr_private_t *priv, dict_t *xattr, int32_t **pending); +afr_set_pending_dict (afr_private_t *priv, dict_t *xattr, int32_t **pending, + int child, afr_xattrop_type_t op); #endif /* __TRANSACTION_H__ */ |