glusterfs.git/tests/bugs, branch v3.4.0beta1

glusterd: big lock - a coarse-grained locking to prevent races

2013-04-17T12:48:50+00:00

There are primarily three lists that are part of glusterd process,
that are concurrently accessed. Namely, priv->volumes, priv->peers
and volinfo->bricks_list.

Big-lock approach
-----------------
WHAT IS IT?
Big lock is a coarse-grained lock which protects all three
lists, mentioned above, from racy access.

HOW DOES IT WORK?
At any given point in time, glusterd's thread(s) are in execution
_iff_ there is a preceding, inbound network event. Of course, the
sigwaiter thread and timer thread are exceptions.
A network event is an external trigger to glusterd, via the epoll
thread, in the form of POLLIN and POLLERR.
As long as we take the big-lock at all such entry points and yield
it when we are done, we are guaranteed that all the network events,
accessing the global lists, are serialised.

This amounts to holding the big lock at
- all the handlers of all the actors in glusterd. (POLLIN)
- all the cbks in glusterd. (POLLIN)
- rpc_notify (DISCONNECT event), if we access/modify
  one of the three lists. (POLLERR)

In the case of synctask'ized volume operations, we must remember that,
if we held the big lock for the entire duration of the handler,
we may block other non-synctask rpc actors from executing.
For eg, volume-start would block in PMAP SIGNIN, if done incorrectly.
To prevent this, we need to yield the big lock, when we yield the
synctask, and reacquire on waking up of the synctask.

BUG: 948686
Change-Id: I429832f1fed67bcac0813403d58346558a403ce9
Signed-off-by: Krishnan Parthasarathi 
Reviewed-on: http://review.gluster.org/4835
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

tests: fix dependency on sleep in bug-874498.t

2013-04-17T11:36:27+00:00

With the introduction of http://review.gluster.org/4784, there are
delays which breaks bug-874498.t which wrongly depends on healing
to finish within 2 seconds.

Fix this by using 'EXPECT_WITHIN 60' instead of sleep 2.

BUG: 874498
Change-Id: I7131699908e63b024d2dd71395b3e94c15fe925c
Original-author: Anand Avati 
Signed-off-by: Krishnan Parthasarathi 
Reviewed-on: http://review.gluster.org/4832
Reviewed-by: Vijay Bellur 
Tested-by: Gluster Build System

tests: fix further issues with bug-874498.t

2013-04-17T08:53:43+00:00

The failure of bug-874498.t seems to be a "bug" in glustershd.
The situation seems to be when both subvolumes of a replica are
"local" to glustershd, and in such cases glustershd is sensitive
to the order in which the subvols come up.

The core of the issue itself is that, without the patch (#4784),
self-heal daemon completes the processing of index and no entries
are left inside the xattrop index after a few seconds of volume
start force. However with the patch, the stale "backing file"
(against which index performs link()) is left. The likely reason
is that an "INDEX" based crawl is not happening against the subvol
when this patch is applied.

Before #4784 patch, the order in which subvols came up was :

[2013-04-09 22:55:35.117679] I [client-handshake.c:1456:client_setvolume_cbk] 0-patchy-client-0: Connected to 10.3.129.13:49156, attached to remote volume '/d/backends/brick1'.
...
[2013-04-09 22:55:35.118399] I [client-handshake.c:1456:client_setvolume_cbk] 0-patchy-client-1: Connected to 10.3.129.13:49157, attached to remote volume '/d/backends/brick2'.

However, with the patch, the order is reversed:

[2013-04-09 22:53:34.945370] I [client-handshake.c:1456:client_setvolume_cbk] 0-patchy-client-1: Connected to 10.3.129.13:49153, attached to remote volume '/d/backends/brick2'.
...
[2013-04-09 22:53:34.950966] I [client-handshake.c:1456:client_setvolume_cbk] 0-patchy-client-0: Connected to 10.3.129.13:49152, attached to remote volume '/d/backends/brick1'.

The index in brick2 has the list of files/gfid to heal. It appears
to be the case that when brick1 is the first subvol to be detected
as coming up, somehow an INDEX based crawl is clearing all the
index entries in brick2, but if brick2 comes up as the first subvol,
then the backing file is left stale.

Also, doing a "gluster volume heal full" seems to leave out stale
backing files too. As the crawl is performed on the namespace and
the backing file is never encountered there to get cleared out.

So the interim (possibly permanent) fix is to have the script issue
a regular self-heal command (and not a "full" one).

The failure of the script itself is non-critical. The data files are
all healed, and it is just the backing file which is left behind. The
stale backing file too gets cleared in the next index based healing,
either triggered manually or after 10mins.

BUG: 874498
Change-Id: I601e9adec46bb7f8ba0b1ba09d53b83bf317ab6a
Original-author: Anand Avati
Signed-off-by: Krishnan Parthasarathi
Reviewed-on: http://review.gluster.org/4831
Tested-by: Gluster Build System
Reviewed-by: Vijay Bellur

glusterd: allow multiple instances of glusterd on one machine

2013-04-16T11:48:58+00:00

This is needed to support automated testing of cluster-communication
features such as probing and quorum.  In order to use this, you need to
do the following preparatory steps.

* Copy /var/lib/glusterd to another directory for each virtual host

* Ensure that each virtual host has a different UUID in its glusterd.info

Now you can start each copy of glusterd with the following xlator-options.

* management.transport.socket.bind-address=$ip_address

* management.working-directory=$unique_working_directory

You can use 127.x.y.z addresses for binding without needing to assign
them to interfaces explicitly.  Note that you must use addresses, not
names, because of some stuff in the socket code that's not worth fixing
just for this usage, but after that you can use names in /etc/hosts
instead.

At this point you can issue CLI commands to a specific glusterd using
the --remote-host option.  So far probe, volume create/start/stop,
mount, and basic I/O all seem to work as expected with multiple
instances.

Change-Id: I1beabb44cff8763d2774bc208b2ffcda27c1a550
BUG: 913555
Original-author: Jeff Darcy 
Signed-off-by: Krishnan Parthasarathi 
Reviewed-on: http://review.gluster.org/4838
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cluster/afr: Preserve mtime in self-heal

2013-04-12T07:22:01+00:00

Problem:
Data self-heal may choose sink iatt to set mtimes.
This happens because after syncing of data is done
self-heal does one more xattrops/fstat to determine
sources sinks to set the inode-ctx. Since this is done
after data syncing and erase of xattrs, old source and
old sink are now sources, but the mtimes of them differ.
Old code just takes the first source from the list and
update mtimes, which could be sink before the self-heal
started.

Fix:
Set mtime from 'sources before syncing'.

Change-Id: Id769e1b99aa4f041eaee775f64cbf2c57b799723
BUG: 918437
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/4658
Reviewed-by: Jeff Darcy 
Tested-by: Gluster Build System 
Reviewed-on: http://review.gluster.org/4663

cluster/distribute: Ignore non-participating subvols for layout checks

2013-04-11T17:41:01+00:00

Backporting fix http://review.gluster.org/#/c/4668/

When subvols-per-directory is < available subvols, then there are layouts
which are not populated. This leads to incorrect identification of holes or
overlaps. We need to ignore layouts, which have err == 0, and start == stop.
In the current scenario (start == stop == 0).

Additionally, in layout-merge, treat missing xattrs as err = 0. In case of
missing layouts, anomalies will reset them.

For any other valid subvoles, err != 0 in case of layouts being zeroed out.

Also reverted back dht_selfheal_dir_xattr, which does layout calculation only
on subvols which have errors.

BUG: 921408
Change-Id: I75a8edcb92af5b53b3253c9addd7a812e9242836
Signed-off-by: shishir gowda 
Reviewed-on: http://review.gluster.org/4800
Reviewed-by: Amar Tumballi 
Reviewed-by: Jeff Darcy 
Tested-by: Gluster Build System

cluster/distribute: Fix layout overlaps due to spread-count in selfheal path

2013-03-09T15:36:34+00:00

We needed to zero out the layout range, before we re-calculate the range.
When spread-count is issued, we would end up with stale ranges in the layout.

Replaced dht_selfheal_dir_xattr with dht_fix_dir_xattr, which correctly resets
the un-used (after re-cal) layouts.

Change-Id: I1a900d15df07335f59356bd23182ccec34381ab2
BUG: 884455
Signed-off-by: shishir gowda 
Reviewed-on: http://review.gluster.org/4648
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

performance/write-behind: Add test case for fd being marked bad after write failures.

2013-03-07T06:37:22+00:00

BUG: 765473
Change-Id: Ia5d9fecc7f84ee4d51f8037e2dd1ed03f0394bd9
Signed-off-by: Raghavendra G 
Reviewed-on: http://review.gluster.org/4632
Reviewed-by: Jeff Darcy 
Tested-by: Gluster Build System

testcase for the open-behind xlator when open fails

2013-03-07T05:31:46+00:00

Test if the fops which are put into a stub and are waiting for
the open to complete should be unwound with the error if open
call itself fails.

Change-Id: I8c363d98303a7df1a0ca9ea6ef207c7123fdd388
BUG: 846240
Original-author: Raghavendra Bhat 
Signed-off-by: Raghavendra Bhat 
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4634
Tested-by: Gluster Build System

tests: move common funtion definitions to include.rc

2013-03-07T05:13:08+00:00

BUG: 765473
Change-Id: Id0d194374d34cfec8ee601090f7fe38b1856ac22
Signed-off-by: Raghavendra G 
Reviewed-on: http://review.gluster.org/4631
Tested-by: Gluster Build System 
Reviewed-by: Jeff Darcy