glusterfs.git/xlators/protocol, branch v4.0dev

program/GF-DUMP: Shield ping processing from traffic to Glusterfs

2017-07-18T10:45:29+00:00

Program

Since poller thread bears the brunt of execution till the request is
handed over to io-threads, poller thread experiencies lock
contention(s) in the control flow till io-threads, which slows it
down. This delay invariably affects reading ping requests from network
and responding to them, resulting in increased ping latencies, which
sometimes results in a ping-timer-expiry on client leading to
disconnect of transport. So, this patch aims to free up poller thread
from executing code of Glusterfs Program. We do this by making

* Glusterfs Program registering itself asking rpcsvc to execute its
  actors in its own threads.
* GF-DUMP Program registering itself asking rpcsvc to _NOT_ execute
  its actors in its own threads. Otherwise program's ownthreads become
  bottleneck in processing ping traffic. This means that poller thread
  reads a ping packet, invokes its actor and hands the response msg to
  transport queue.

Change-Id: I526268c10bdd5ef93f322a4f95385137550a6a49
Signed-off-by: Raghavendra G 
BUG: 1421938
Reviewed-on: https://review.gluster.org/17105
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Smoke: Gluster Build System 
Reviewed-by: Amar Tumballi 
Reviewed-by: Jeff Darcy

mgtm/core : use sha hash function for volfile check

2017-07-10T05:07:11+00:00

We are storing the entire volfile and using this to check
volfile change. With brick multiplexing there will be lot
of graphs per process which will increase the memory foot
print of the process. So instead of storing the entire
graph we could use sha256 and we can compare the hash to
see whether volfile change happened or not.

Also with Brick multiplexing, the direct comparison of vol
file is not correct. There are two problems.

Problem 1:

We are currently storing one single graph (the last
updated volfile) whereas, what we need is the entire
graph with all atttached bricks.

If we fix this issue, we have second problem

Problem 2:
With multiplexing we have a graph that contains multiple
bricks. But what we are checking as part of the reconfigure
is, comparing the entire graph with one single graph,
which will always fail.

Solution:
We create list in glusterfs_ctx_t that stores sha256 hash
of individual brick graphs. When a graph changes happens
we compare the stored hash and the current hash. If the
hash matches, then no need for reconfigure. Otherwise we
first do the reconfigure and then update the hash.

For now, gfapi has not changed this way. Meaning when gfapi
volfile fetch or reconfigure happens, we still store the
entire graph and compare, each memory.

This is fine, because libgfapi will not load brick graphs.
But changing the libgfapi will make the code similar in
both glusterfsd-mgmt and api. Also it helps to reduce some
memory.

Change-Id: I9df917a771a52b95622ab8f63af34ec390163a77
BUG: 1467986
Signed-off-by: Mohammed Rafi KC 
Reviewed-on: https://review.gluster.org/17709
Smoke: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri 
CentOS-regression: Gluster Build System 
Reviewed-by: Atin Mukherjee 
Reviewed-by: Amar Tumballi

groups: don't allocate auxiliary gid list on stack

2017-07-06T18:26:08+00:00

When glusterfs wants to retrieve the list of auxiliary gids
of a user, it typically allocates a sufficiently big gid_t
array on stack and calls getgrouplist(3) with it. However,
"sufficiently big" means to be of maximum supported gid list
size, which in GlusterFS is GF_MAX_AUX_GROUPS = 64k.
That means a 64k * sizeof(gid_t) = 256k allocation, which is
big enough to overflow the stack in certain cases.

A further observation is that stack allocation of the gid list
brings no gain, as in all cases the content of the gid list
eventually gets copied over to a heap allocated buffer.

So we add a convenience wrapper of getgrouplist to libglusterfs
called gf_getgrouplist which calls getgrouplist with a sufficiently
big heap allocated buffer (it takes care of the allocation too).
We are porting all the getgrouplist invocations to gf_getgrouplist
and thus eliminate the huge stack allocation.

BUG: 1464327
Change-Id: Icea76d0d74dcf2f87d26cb299acc771ca3b32d2b
Signed-off-by: Csaba Henk 
Reviewed-on: https://review.gluster.org/17706
Smoke: Gluster Build System 
Reviewed-by: Niels de Vos 
Reviewed-by: Amar Tumballi 
CentOS-regression: Gluster Build System

Link against missed libraries to resolve symbols

2017-07-03T10:58:14+00:00

When external programs perform a dlopen("..so", RTLD_LAZY|RTLD_LOCAL)
on some shared objects like xlators, it can fail with dlerror set to
error string "undefined symbol ".

This was observed for the following shared objects: fuse.so, quota.so,
quotad.so, server.so, libgfrpc.so and socket.so

P.S: This was found while running a go program which fetches the list
of xlator options (volume_option_t) from xlator's shared object.

BUG: 1193929
Change-Id: I7b958409cf11fb67c2be32a3f85a96fb1260236b
Signed-off-by: Prashanth Pai 
Reviewed-on: https://review.gluster.org/17659
Smoke: Gluster Build System 
Reviewed-by: Amar Tumballi 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Jeff Darcy

multiple: fix struct/typedef inconsistencies

2017-06-30T10:31:02+00:00

The most common pattern, both in our code and elsewhere, is this:

   struct _xyz {
      ...
   };
   typedef struct _xyz xyz_t;

These exceptions - especially call_frame/call_stack - have been slowing
down code navigation for years.  By converging on a single pattern,
navigating from xyz_t in code to the actual definition of struct _xyz
(i.e. without having to visit the typedef first) might even be
automatable.

Change-Id: I0e5dd1f51f98e000173c62ef4ddc5b21d9ec44ed
Signed-off-by: Jeff Darcy 
Reviewed-on: https://review.gluster.org/17650
Smoke: Gluster Build System 
Tested-by: Jeff Darcy 
CentOS-regression: Gluster Build System 
Reviewed-by: Amar Tumballi 
Reviewed-by: Niels de Vos

protocol/server: make listen backlog value as configurable

2017-06-08T15:32:30+00:00

problem:

When we call listen from protocol/server, we are giving a
hard coded valie of 10 if it is not manually given.
With multiplexing, especially when glusterd restarts all
clients may try to connect to the server at a time.
Which will result in overflowing the queue, and kernel
will complain about the errors.

Solution:

This patch will introduce a volume set command to make backlog
value as a configurable. This patch also changes the default
values for backlog from 10 to 128. This changes is only applicable
for sockets listening from protocol.

Example:

gluster volume set  transport.listen-backlog 1024

Note: 1 Brick has to be restarted to get this value in effect
      2 This changes won't be reflected in glusterd, or other
        xlators which calls listen. If you need, you have to
        add this option to the volfile.

Change-Id: I0c5a2bbf28b5db612f9979e7560e05dd82b41477
BUG: 1456405
Signed-off-by: Mohammed Rafi KC 
Reviewed-on: https://review.gluster.org/17411
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G 
Reviewed-by: Raghavendra Talur 
Reviewed-by: Atin Mukherjee 
Reviewed-by: Niels de Vos 
Reviewed-by: Jeff Darcy

dht: for many operation directory/file path is (null) in brick log

2017-06-05T03:27:07+00:00

There are few operations on mount point which results to 
(null) error for path on brick log. This should be corrected with
correct path. 

Change-Id: I5acf2ead5196594c76a2e526aafbfc128ece433e
BUG: 1456361
Signed-off-by: ankitraj 
Reviewed-on: https://review.gluster.org/17407
Smoke: Gluster Build System 
Tested-by: ankitraj
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G

glusterfs: Not able to mount running volume after enable brick mux and stopped any volume

2017-05-31T20:43:53+00:00

Problem: After enabled brick mux if any volume has down and then try ot run mount
         with running volume , mount command is hung.

Solution: After enable brick mux server has shared one data structure server_conf
          for all associated subvolumes.After down any subvolume in some
          ungraceful manner (remove brick directory) posix xlator sends
          GF_EVENT_CHILD_DOWN event to parent xlatros and server notify
          updates the child_up to false in server_conf.When client is trying
          to communicate with server through mount it checks conf->child_up
          and it is FALSE so it throws message "translator are not yet ready".
          From this patch updated structure server_conf to save child_up status
          for xlator wise. Another improtant correction from this patch is
          cleanup threads from server side xlators after stop the volume.

BUG: 1453977
Change-Id: Ic54da3f01881b7c9429ce92cc569236eb1d43e0d
Signed-off-by: Mohit Agrawal 
Reviewed-on: https://review.gluster.org/17356
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Raghavendra Talur 
CentOS-regression: Gluster Build System 
Reviewed-by: Jeff Darcy

glusterfsd: process attach and detach request inside lock

2017-05-26T12:11:28+00:00

With brick multiplexing, there is a high possibility that attach and
detach requests might be parallely processed and to avoid a concurrent
update to the same graph list, a mutex lock is required.

Credits : Rafi (rkavunga@redhat.com) for the RCA of this issue

Change-Id: Ic8e6d1708655c8a143c5a3690968dfa572a32a9c
BUG: 1454865
Signed-off-by: Atin Mukherjee 
Reviewed-on: https://review.gluster.org/17374
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Jeff Darcy

libglusterfs: fix race condition in client_ctx_set

2017-05-12T04:47:44+00:00

	follow procedures:
	1.thread1 client_ctx_get return NULL
	2.thread 2 client_ctx_set ctx1 ok
	3.thread1 client_ctx_set ctx2 ok

	thread1 use ctx1, thread2 use ctx2 and ctx1 will leak

Change-Id: I990b02905edd1b3179323ada56888f852d20f538
BUG: 1449232
Signed-off-by: Zhou Zhengping 
Reviewed-on: https://review.gluster.org/17219
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G 
Smoke: Gluster Build System 
Reviewed-by: Jeff Darcy