glusterfs.git/xlators/features/changelog/src, branch v3.12dev

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

features/changelog: fix a bug in changelog_rpc_server_destroy

2017-01-30T20:18:18+00:00

the programe unregister loop never get moved forward, it's a dead loop.
to resolve it, add progs++ in the loop.

Change-Id: Ib25ded10b3ce808e2fb57b13d767833f24cf01a7
BUG: 1369393
Signed-off-by: Ryan Ding 
Reviewed-on: https://review.gluster.org/15292
Smoke: Gluster Build System 
Reviewed-by: Prashanth Pai 
Tested-by: Kotresh HR 
Reviewed-by: Kotresh HR 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Jeff Darcy

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

features/changelog: Fix htime xattr during brick crash

2017-01-19T09:39:42+00:00

The htime file contains the path of all the changelogs
that is rolloved over till now. It also maintains xattr
which tracks the latest changelog file rolloved over
and the number of changelogs. The path and and xattr
update happens in two different system calls. If the
brick is crashed between them, the xattr value becomes
stale and can lead to the failure of gf_history_changelog.
To identify this, the total number of changelogs is being
calculated based on htime file size and the record
length. The above value is used in case of mismatch.

Change-Id: Ia1c3efcfda7b74227805bb2eb933c9bd4305000b
BUG: 1413967
Signed-off-by: Kotresh HR 
Reviewed-on: http://review.gluster.org/16420
NetBSD-regression: NetBSD Build System 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Aravinda VK

build: out-of-tree builds generates files in the wrong directory

2016-09-18T16:34:37+00:00

And minor cleanup of a few of the Makefile.am files while we're
at it.

Rewrite the make rules to do what xdrgen does. Now we can get rid
of xdrgen.

Note 1. netbsd6's sed doesn't do -i. Why are we still running
smoke tests on netbsd6 and not netbsd7? We barely support netbsd7
as it is.

Note 2. Why is/was libgfxdr.so (.../rpc/xdr/src/...) linked with
libglusterfs? A cut-and-paste mistake? It has no references to
symbols in libglusterfs.

Note3. "/#ifndef\|#define\|#endif/" (note the '\'s) is a _basic_
regex that matches the same lines as the _extended_ regex
"/#(ifndef|define|endif)/". To match the extended regex sed needs to
be run with -r on Linux; with -E on *BSD. However NetBSD's and
FreeBSD's sed helpfully also provide -r for compatibility. Using a
basic regex avoids having to use a kludge in order to run sed with
the correct option on OS X.

Note 4. Not copying the bit of xdrgen that inserts copyright/license
boilerplate. AFAIK it's silly to pretend that machine generated
files like these can be copyrighted or need license boilerplate.
The XDR source files have their own copyright and license; and
their copyrights are bound to be more up to date than old
boilerplate inserted by a script. From what I've seen of other
Open Source projects -- e.g. gcc and its C parser files generated
by yacc and lex -- IIRC they don't bother to add copyright/license
boilerplate to their generated files.

It appears that it's a long-standing feature of make (SysV, BSD,
gnu) for out-of-tree builds to helpfully pretend that the source
files it can find in the VPATH "exist" as if they are in the $cwd.
rpcgen doesn't work well in this situation and generates files
with "bad" #include directives.

E.g. if you `rpcgen ../../../../$srcdir/rpc/xdr/src/glusterfs3-xdr.x`,
you get an #include directive in the generated .c file like this:

  ...
  #include "../../../../$srcdir/rpc/xdr/src/glusterfs3-xdr.h"
  ...

which (obviously) results in compile errors on out-of-tree build
because the (generated) header file doesn't exist at that location.
Compared to `rpcgen ./glusterfs3-xdr.x` where you get:

  ...
  #include "glusterfs3-xdr.h"
  ...

Which is what we need. We have to resort to some Stupid Make Tricks
like the addition of various .PHONY targets to work around the VPATH
"help".

Warning: When doing an in-tree build, -I$(top_builddir)/rpc/xdr/...
looks exactly like -I$(top_srcdir)/rpc/xdr/...  Don't be fooled though.
And don't delete the -I$(top_builddir)/rpc/xdr/... bits

Change-Id: Iba6ab96b2d0a17c5a7e9f92233993b318858b62e
BUG: 1330604
Signed-off-by: Kaleb S KEITHLEY 
Reviewed-on: http://review.gluster.org/14085
Tested-by: Niels de Vos 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Niels de Vos

features/changelog: fix a segment fault in changelog_cleanup_dispatchers

2016-09-02T10:24:41+00:00

the arg 'count' in changelog_cleanup_dispatchers means the thread count
to cleanup, so the cleanup loop should start with count-1, not count.
change the invoke place also.

Change-Id: Ia00853a2e0c5e01e145f60048b1f0ac05f2440ab
BUG: 1369397
Signed-off-by: Ryan Ding 
Reviewed-on: http://review.gluster.org/15293
Smoke: Gluster Build System 
Reviewed-by: Kotresh HR 
Tested-by: Kotresh HR 
Reviewed-by: Milind Changire 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

core: fix unused variable warnings/errors

2016-08-29T16:21:56+00:00

http://review.gluster.org/14085 fixes a/the "leak" - via the
generated rpc/xdr headers - of pragmas that mask these warnings.

However 14085 won't pass the smoke test until all the warnings are
fixed.

Change-Id: I3d8a7a3de35058aa97eab59d3f59208396298b03
BUG: 1369124
Signed-off-by: Kaleb S. KEITHLEY 
Reviewed-on: http://review.gluster.org/15246
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Kotresh HR

changelog/rpc: Fix rpc_clnt_t mem leaks

2016-07-22T15:12:52+00:00

PROBLEM:
   1. Freeing up rpc_clnt object might lead to crashes. Well,
      it was not a necessity to free rpc-clnt object till now
      because all the existing use cases needs to reconnect
      back on disconnects. Hence timer code was not taking
      ref on rpc-clnt object.

      Glusterd had some use-cases that led to crash due to
      ping-timer and they fixed only those code paths that
      involve ping-timer.

      Now, since changelog has an use-case where rpc-clnt
      need to be freed up, we need to fix timer code to take
      refs

   2. In changelog, because of issue 1, only mydata was being
      freed which is incorrect. And there are races where
      rpc-clnt object would access the freed mydata which
      would lead to crashes.

      Since changelog xlator resides on brick side and is long
      living process, if multiple libgfchangelog consumers
      register to changelog and disconnect/reconnect mulitple
      times, it would result in leak of 'rpc-clnt' object
      for every connect/disconnect.

SOLUTION:
   1. Handle ref/unref of 'rpc_clnt' structure in timer
      functions properly.
   2. In changelog, unref 'rpc_clnt' in RPC_CLNT_DISCONNECT
      after disabling timers and free mydata on RPC_CLNT_DESTROY.

RPC SETUP IN CHANGELOG:
   1. changelog xlator initiates rpc server say 'changelog_rpc_server'
   2. libgfchangelog initiates one rpc server say 'libgfchangelog_rpc_server'
   3. libgfchangelog initiates rpc client and connects to 'changelog_rpc_server'
   4. In return changelog_rpc_server initiates a rpc client and connects back
      to 'libgfchangelog_rpc_server'

REF/UNREF HANDLING IN TIMER FUNCTIONS:
Let's say rpc clnt refcount = 1
   1. Take the ref before reigstering callback to timer queue
           >>>>  rpc_clnt_ref (say ref count becomes = 2)
   2. Register a callback to timer say 'callback1'
   3. If register fails:
           >>>> rpc_clnt_unref (ref count = 1)
   4. On timer expiration, 'callback1' gets called. So unref rpc clnt at the end
      in 'callback1'. This is corresponding to ref taken in step 1
           >>>> rpc_clnt_unref (ref count = 1)
   5. The cycle from step-1 to step-4 continues....until timer cancel event happens
   6. timer cancel of say 'callback1'
           If timer cancel fails:
                 Do nothing, Step-4 would have unrefd
           If timer cancel succeeds:
                 >>>> rpc_clnt_unref (ref count = 1)

Change-Id: I91389bc511b8b1a17824941970ee8d2c29a74a09
BUG: 1316178
Signed-off-by: Kotresh HR 
Reviewed-on: http://review.gluster.org/13658
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra G

core: use readdir(3) with glibc, and associated cleanup

2016-07-18T11:59:42+00:00

Starting with glibc-2.23 (i.e. what's in Fedora 25), readdir_r(3)
is marked as deprecated. Specifically the function decl in 
has the deprecated attribute, and now warnings are thrown during the
compile on Fedora 25 builds.

The readdir(_r)(3) man page (on Fedora 25 at least) and World+Dog say
that glibc's readdir(3) is, and always has been, MT-SAFE as long as
only one thread is accessing the directory object returned by opendir().
World+Dog also says there is a potential buffer overflow in readdir_r().
World+Dog suggests that it is preferable to simply use readdir(). There's
an implication that eventually readdir_r(3) will be removed from glibc.
POSIX has, apparently deprecated it in the standard, or even removed it
entirely.

Over and above that, our source near the various uses of readdir(_r)(3)
has a few unsafe uses of strcpy()+strcat().

(AFAIK nobody has looked at the readdir(3) implemenation in *BSD to see
if the same is true on those platforms, and we can't be sure of MacOS
even though we know it's based on *BSD.)

Change-Id: I5481f18ba1eebe7ee177895eecc9a80a71b60568
BUG: 1356998
Signed-off-by: Kaleb S. KEITHLEY 
Reviewed-on: http://review.gluster.org/14838
Smoke: Gluster Build System 
Reviewed-by: Niels de Vos 
CentOS-regression: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Kotresh HR 
Reviewed-by: Jeff Darcy

features/changelog: Change barrier notification mechanism

2016-05-31T18:59:58+00:00

The barrier notification mechanism was fd based and 'select'
was being used. 'select' breaks when number of fds opened
by brick process exceeds 1024. To avoid this and also
the maintainance of pipe between notify and 'changelog_rollover',
the pipe has been replaced with pthread condition signal
and timed wait mechanism.

Change-Id: I530ea90d9a06953f8b23b4e12d122872ee1925de
BUG: 1334314
Signed-off-by: Kotresh HR 
Reviewed-on: http://review.gluster.org/14272
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Aravinda VK 
CentOS-regression: Gluster Build System 
Reviewed-by: Raghavendra Bhat 
Reviewed-by: Jeff Darcy