glusterfs.git/xlators/protocol/client, branch v3.11.0

Halo Replication feature for AFR translator

2017-05-08T05:37:07+00:00

	Backport of https://review.gluster.org/16177
		    https://review.gluster.org/17174

Merged both these patches to make sure IPV6 changes don't make it to 3.11 at all.

Summary:
Halo Geo-replication is a feature which allows Gluster or NFS clients to write
locally to their region (as defined by a latency "halo" or threshold if you
like), and have their writes asynchronously propagate from their origin to the
rest of the cluster.  Clients can also write synchronously to the cluster
simply by specifying a halo-latency which is very large (e.g. 10seconds) which
will include all bricks.

In other words, it allows clients to decide at mount time if they desire
synchronous or asynchronous IO into a cluster and the cluster can support both
of these modes to any number of clients simultaneously.

There are a few new volume options due to this feature:
  halo-shd-latency:  The threshold below which self-heal daemons will
  consider children (bricks) connected.

  halo-nfsd-latency: The threshold below which NFS daemons will consider
  children (bricks) connected.

  halo-latency: The threshold below which all other clients will
  consider children (bricks) connected.

  halo-min-replicas: The minimum number of replicas which are to
  be enforced regardless of latency specified in the above 3 options.
  If the number of children falls below this threshold the next
  best (chosen by latency) shall be swapped in.

New FUSE mount options:
  halo-latency & halo-min-replicas: As descripted above.

This feature combined with multi-threaded SHD support (D1271745) results in
some pretty cool geo-replication possibilities.

Operational Notes:
- Global consistency is gaurenteed for synchronous clients, this is provided by
  the existing entry-locking mechanism.
- Asynchronous clients on the other hand and merely consistent to their region.
  Writes & deletes will be protected via entry-locks as usual preventing
  concurrent writes into files which are undergoing replication.  Read operations
  on the other hand should never block.
- Writes are allowed from _any_ region and propagated from the origin to all
  other regions.  The take away from this is care should be taken to ensure
  multiple writers do not write the same files resulting in a gfid split-brain
  which will require resolution via split-brain policies (majority, mtime &
  size).  Recommended method for preventing this is using the nfs-auth feature to
  define which region for each share has RW permissions, tiers not in the origin
  region should have RO perms.

TODO:
- Synchronous clients (including the SHD) should choose clients from their own
  region as preferred sources for reads.  Most of the plumbing is in place for
  this via the child_latency array.
- Better GFID split brain handling & better dent type split brain handling
  (i.e. create a trash can and move the offending files into it).
- Tagging in addition to latency as a means of defining which children you wish
  to synchronously write to

Test Plan:
- The usual suspects, clang, gcc w/ address sanitizer & valgrind
- Prove tests

Reviewers: jackl, dph, cjh, meyering

Reviewed By: meyering

Subscribers: ethanr

Differential Revision: https://phabricator.fb.com/D1272053

Tasks: 4117827

 >Change-Id: I694a9ab429722da538da171ec528406e77b5e6d1
 >BUG: 1428061
 >Signed-off-by: Kevin Vigor 
 >Reviewed-on: http://review.gluster.org/16099
 >Reviewed-on: https://review.gluster.org/16177
 >Tested-by: Pranith Kumar Karampuri 
 >Smoke: Gluster Build System 
 >NetBSD-regression: NetBSD Build System 
 >CentOS-regression: Gluster Build System 
 >Reviewed-by: Pranith Kumar Karampuri 

BUG: 1448416
Change-Id: I694a9ab429722da538da171ec528406e77b5e6d1
Signed-off-by: Pranith Kumar K 
Reviewed-on: https://review.gluster.org/17192
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Kaushal M

protocol-client: Initialize the list_head before using

2017-03-27T00:56:19+00:00

In client3_3_readdir(p)_cbk, in case of error conditions,
it is possible that the list_head is used before initializing.
Hence move the initialization before usage.

Change-Id: Ie58902d079fdc58416d17b5fa5f61375decb1c99
BUG: 1435943
Signed-off-by: Poornima G 
Reviewed-on: https://review.gluster.org/16948
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G

rpc/clnt: remove locks while notifying CONNECT/DISCONNECT

2017-03-01T14:35:48+00:00

Locking during notify was introduced as part of commit
aa22f24f5db7659387704998ae01520708869873 [1]. The fix was introduced
to fix out-of-order CONNECT/DISCONNECT events from rpc-clnt to parent
xlators [2]. However as part of handling DISCONNECT protocol/client
does unwind saved frames (with failure) waiting for responses. This
saved_frames_unwind can be a costly operation and hence ideally
shouldn't be included in the critical section of notifylock, as it
unnecessarily delays the reconnection to same brick. Also, its not a
good practise to pass control to other xlators holding a lock as it
can lead to deadlocks. So, this patch removes locking in rpc-clnt
while notifying parent xlators.

To fix [2], two changes are present in this patch:

* notify DISCONNECT before cleaning up rpc connection (same as commit
  a6b63e11b7758cf1bfcb6798, patch [3]).
* protocol/client uses rpc_clnt_cleanup_and_start, which cleans up rpc
  connection and does a start while handling a DISCONNECT event from
  rpc. Note that patch [3] was reverted as rpc_clnt_start called in
  quick_reconnect path of protocol/client didn't invoke connect on
  transport as the connection was not cleaned up _yet_ (as cleanup was
  moved post notification in rpc-clnt). This resulted in clients never
  attempting connect to bricks.

Note that one of the neater ways to fix [2] (without using locks) is
to introduce generation numbers to map CONNECT and DISCONNECTS across
epochs and ignore DISCONNECT events if they don't belong to current
epoch. However, this approach is a bit complex to implement and
requires time. So, current patch is a hacky stop-gap fix till we come
up with a more cleaner solution.

[1] http://review.gluster.org/15916
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1386626
[3] http://review.gluster.org/15681

Change-Id: I62daeee8bb1430004e28558f6eb133efd4ccf418
Signed-off-by: Raghavendra G 
BUG: 1427012
Reviewed-on: https://review.gluster.org/16784
Smoke: Gluster Build System 
Reviewed-by: Milind Changire 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

protocol/client: Add gfid in request for better tcpdumps

2017-02-28T04:28:07+00:00

It is difficult to match opendir/releasedir or
open/release calls without gfid associlation to find
fd-leaks on the bricks. So assigning gfid also in
the request which was already there in the on-wire
format.

BUG: 1425676
Change-Id: Iec908eeaa2f97295d45140a529b7f8fb834a1553
Signed-off-by: Pranith Kumar K 
Reviewed-on: https://review.gluster.org/16706
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G

libglusterfs, gfdb, glusterfs: Add missing breaks

2017-02-26T16:29:26+00:00

A few switches did not have breaks causing fall throughs. Most of them
have been fixed with fall through comments for those that are
intentional.

Change-Id: I84c85726b542f38504b50fefab5eba5dbcd27a07
BUG: 1424894
Signed-off-by: Nigel Babu 
Reviewed-on: https://review.gluster.org/16677
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Smoke: Gluster Build System 
Reviewed-by: Jeff Darcy 
Reviewed-by: Shyamsundar Ranganathan

protocol/client: Fix double free of client fdctx destroy

2017-02-13T11:29:23+00:00

This patch fixes the race between fd re-open code and fd release code,
both of which free the fd context due to a race in certain variable
checks as explained below:

1. client process (shd in the case of this BZ) sends an opendir to its
children (client xlators) which send the fop to the bricks to get a valid fd.

2. Client xlator loses connection to the brick. fdctx->remotefd is -1

3. Client re-establishes connection. After handshake, it reopens the dir
and sets fdctx->remotefd to a valid fd in client3_3_reopendir_cbk().

4. Meanwhile, shd sends a fd unref after it is done with the opendir.
This triggers a releasedir (since fd->refcount becomes 0).

5. client3_3_releasedir() sees that fdctx-->remotefd is a valid number
(i.e not -1), sets fdctx->released=1 and calls  client_fdctx_destroy()

6. As a continuation of step3, client_reopen_done() is called by
client3_3_reopendir_cbk(), which sees that fdctx->released==1 and
again calls client_fdctx_destroy().

Depending on when step-5 does GF_FREE(fdctx), we may crash at any place in
step-6 in client3_3_reopendir_cbk() when it tries to access
fdctx->{whatever}.

Change-Id: Ia50873d11763e084e41d2a1f4d53715438e5e947
BUG: 1418629
Signed-off-by: Ravishankar N 
Reviewed-on: https://review.gluster.org/16521
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Smoke: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri

core: run many bricks within one glusterfsd process

2017-01-31T00:13:58+00:00

This patch adds support for multiple brick translator stacks running
in a single brick server process.  This reduces our per-brick memory usage by
approximately 3x, and our appetite for TCP ports even more.  It also creates
potential to avoid process/thread thrashing, and to improve QoS by scheduling
more carefully across the bricks, but realizing that potential will require
further work.

Multiplexing is controlled by the "cluster.brick-multiplex" global option.  By
default it's off, and bricks are started in separate processes as before.  If
multiplexing is enabled, then *compatible* bricks (mostly those with the same
transport options) will be started in the same process.

Change-Id: I45059454e51d6f4cbb29a4953359c09a408695cb
BUG: 1385758
Signed-off-by: Jeff Darcy 
Reviewed-on: https://review.gluster.org/14763
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Vijay Bellur

gluster: Typos in logs and comments

2017-01-19T20:37:08+00:00

Replaced 'recieve' with 'receive'.

Change-Id: I4c1c9147db5437feb81e4c83ed074440aaa28e07
BUG: 1414645
Signed-off-by: N Balachandran 
Reviewed-on: http://review.gluster.org/16429
Smoke: Gluster Build System 
Reviewed-by: Manikandan Selvaganesh 
Tested-by: Manikandan Selvaganesh 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Jeff Darcy

glusterd: Add info on op-version for clients in vol status output

2017-01-12T18:20:59+00:00

Currently the `gluster volume status  clients` command
gives us the following information on clients:
1. Brick name
2. Client count for each brick
3. hostname:port for each client
4. Bytes read and written for each client

There is no information regarding op-version for each client. This
patch adds that to the output.

Change-Id: Ib2ece93ab00c234162bb92b7c67a7d86f3350a8d
BUG: 1409078
Signed-off-by: Samikshan Bairagya 
Reviewed-on: http://review.gluster.org/16303
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Atin Mukherjee

socket: socket disconnect should wait for poller thread exit

2016-12-22T04:49:19+00:00

When SSL is enabled or if "transport.socket.own-thread" option is set
then socket_poller is run as different thread. Currently during
disconnect or PARENT_DOWN scenario we don't wait for this thread
to terminate. PARENT_DOWN will disconnect the socket layer and
cleanup resources used by socket_poller.

Therefore before disconnect we should wait for poller thread to exit.

Change-Id: I71f984b47d260ffd979102f180a99a0bed29f0d6
BUG: 1404181
Signed-off-by: Rajesh Joseph 
Reviewed-on: http://review.gluster.org/16141
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Kaushal M 
Reviewed-by: Raghavendra Talur 
Reviewed-by: Raghavendra G