path: root/xlators/storage/posix/src
diff options
authorVenkatesh Somyajulu <>2014-07-25 17:21:04 +0530
committerVijay Bellur <>2014-07-31 22:46:34 -0700
commit966997992bdbd5fffc632bf705678e287ed50bf7 (patch)
tree47ca125dd73129a2ead6646bacbaf61942170904 /xlators/storage/posix/src
parent9de6d8b555a5202cbf80753f41efa03032edb02b (diff)
cluster/dht: Modified logic of linkto file deletion on non-hashed
Currently whenever dht_lookup_everywhere gets called, if in dht_lookup_everywhere_cbk, a linkto file is found on non-hashed subvolume, file is unlinked. But there are cases when this file is under migration. Under such condition, we should avoid deletion of file. When some other rebalance process changes the layout of parent such that dst_file (w.r.t. migration) falls on non-hashed node, then may be lookup could have found it as linkto file but just before unlink, file is under migration or already migrated In such cased unlink can be avoided. Race: ------- If we have two bricks (brick-1 and brick-2) with initial file "a" under BaseDir which is hashed as well as cached on (brick-1). Assume "a" hashing gives 44. Brick-1 Brick-2 Initial Setup: BaseDir/a BaseDir [1-50] [51-100] Now add new-brick Brick-3. 1. Rebalance-1 on node Node-1 (Brick-1 node) will reset the BaseDir Layout. 2. After that it will perform a) Create linkto file on new-hashed (brick-2) b) Perform file migration. 1.Rebalance-1 Fixes the base-layout: Brick-1 Brick-2 Brick-3 --------- ---------- ------------ BaseDir/a BaseDir BaseDir [1-33] [34-66] [67-100] 2. Only a) is BaseDir/a BaseDir/a(linkto) BaseDir performed Create linktofile Now rebalance 2 on node-2 jumped in and it will perform step 1 and 2-a. After (rebal-2, step-1), it changes the layout of the BaseDir. BaseDir/a BaseDir/a(link) BaseDir [67-100] [1-33] [34-66] For (rebale-2, step-2), It will perform lookup at Brick-3 as w.r.t new layout 44 falls for brick-3. But lookup will fail. So dht_lookup_everywhere gets called. NOTE: On brick-2 by rebalance-1, a linkto file was created. Currently that linkto files gets deleted by rebalance-2 lookup as it is considered as stale linkto file. But with patch if rebalance is already in progress or rebalance is over, linkto file will not be unlinked. If rebalance is in progress fd will be open and if rebalance is over then linkto file wont be set. Change-Id: I3fee0d28de3c76197325536a9e30099d2413f079 BUG: 1116150 Signed-off-by: Venkatesh Somyajulu <> Reviewed-on: Tested-by: Gluster Build System <> Reviewed-by: Raghavendra G <> Reviewed-by: Shyamsundar Ranganathan <> Reviewed-by: Vijay Bellur <>
Diffstat (limited to 'xlators/storage/posix/src')
1 files changed, 2 insertions, 2 deletions
diff --git a/xlators/storage/posix/src/posix.c b/xlators/storage/posix/src/posix.c
index 16188a2..5decac2 100644
--- a/xlators/storage/posix/src/posix.c
+++ b/xlators/storage/posix/src/posix.c
@@ -1399,7 +1399,7 @@ posix_unlink (call_frame_t *frame, xlator_t *this,
priv = this->private;
- op_ret = dict_get_int32 (xdata, "dont-unlink-for-open-fd",
+ op_ret = dict_get_int32 (xdata, DHT_SKIP_OPEN_FD_UNLINK,
if (!op_ret && check_open_fd) {
@@ -1420,7 +1420,7 @@ posix_unlink (call_frame_t *frame, xlator_t *this,
- op_ret = dict_get_int32 (xdata, "unlink-only-if-dht-linkto-file",
+ op_ret = dict_get_int32 (xdata, DHT_SKIP_NON_LINKTO_UNLINK,
if (!op_ret && unlink_if_linkto) {