glusterfs-snapshot.git/xlators/features/marker/src, branch development

glusterfs: zerofill support

2013-11-11T05:25:49+00:00

Add support for a new ZEROFILL fop. Zerofill writes zeroes to a file in
the specified range. This fop will be useful when a whole file needs to
be initialized with zero (could be useful for zero filled VM disk image
provisioning or  during scrubbing of VM disk images).

Client/application can issue this FOP for zeroing out. Gluster server
will zero out required range of bytes ie server offloaded zeroing. In
the absence of this fop,  client/application has to repetitively issue
write (zero) fop to the server, which is very inefficient method because
of the overheads involved in RPC calls  and acknowledgements.

WRITESAME is a  SCSI T10 command that takes a block of data as input and
writes the same data to other blocks and this write is handled
completely within the storage and hence is known as offload . Linux ,now
has support for SCSI WRITESAME command which is exposed to the user in
the form of BLKZEROOUT ioctl.  BD Xlator can exploit BLKZEROOUT ioctl to
implement this fop. Thus zeroing out operations can be completely
offloaded to the storage device , making it highly efficient.

The fop takes two arguments offset and size. It zeroes out 'size' number
of bytes in an opened file starting from 'offset' position.

This patch adds zerofill support to the following areas:
	- libglusterfs
	- io-stats
	- performance/md-cache,open-behind
	- quota
	- cluster/afr,dht,stripe
	- rpc/xdr
	- protocol/client,server
	- io-threads
	- marker
	- storage/posix
	- libgfapi

Client applications can exloit this fop by using glfs_zerofill introduced in
libgfapi.FUSE support to this fop has not been added as there is no system call
for this fop.

Changes from previous version 3:
* Removed redundant memory failure log messages

Changes from previous version 2:
* Rebased and fixed build error

Changes from previous version 1:
* Rebased for latest master

TODO :
     * Add zerofill support to trace xlator
     * Expose zerofill capability as part of gluster volume info

Here is a performance comparison of server offloaded zeofill vs zeroing
out using repeated writes.

[root@llmvm02 remote]# time ./offloaded aakash-test log 20

real	3m34.155s
user	0m0.018s
sys	0m0.040s
[root@llmvm02 remote]# time ./manually aakash-test log 20

real	4m23.043s
user	0m2.197s
sys	0m14.457s
[root@llmvm02 remote]# time ./offloaded aakash-test log 25;

real	4m28.363s
user	0m0.021s
sys	0m0.025s
[root@llmvm02 remote]# time ./manually aakash-test log 25

real	5m34.278s
user	0m2.957s
sys	0m18.808s

The argument log is a file which we want to set for logging purpose and
the third argument is size in GB .

As we can see there is a performance improvement of around 20% with this
fop.

Change-Id: I081159f5f7edde0ddb78169fb4c21c776ec91a18
BUG: 1028673
Signed-off-by: Aakash Lal Das 
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/5327
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

features/marker: force xtime updates (configurable) for client-pid = -1

2013-09-05T03:43:03+00:00

This is required by Geo-Replication that does auxillary mount
with client-pid as -1 (which has special treatment at specific
places in GlusterFS), to trigger xtime updates on the intermediate
master in a cascading setup.

Marker too had a check to "not" mark updates for geo-replication's
auxillary mounts. With the new geo-replication design, xtimes are
not set by the master on the slave for all entities. Due to this
cascading setups were broken.

This patch introduces "geo-replication.ignore-pid-check" option
as a "override" for the client-pid check for gsyncd's client-pid.
When this options is enabled, marker start "marking" even if the
updates are from the special client.

Geo-Replication on the detection of itself being an intermediate
master, enables this option.

Change-Id: I9f7140edd12fef5480595ee0f93f35b94cdb8345
BUG: 996371
Signed-off-by: Venky Shankar 
Reviewed-on: http://review.gluster.org/5591
Tested-by: Gluster Build System 
Reviewed-by: Avra Sengupta 
Tested-by: Avra Sengupta 
Reviewed-by: Anand Avati

features/marker: pass xdata in marker_unlink()

2013-07-24T17:41:30+00:00

Change-Id: Ia310af96b25f29351f3adc4bbc97aea271df7673
BUG: 987747
Signed-off-by: Venky Shankar 
Reviewed-on: http://review.gluster.org/5379
Reviewed-by: Amar Tumballi 
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

glusterfs: discard (hole punch) support

2013-06-13T21:37:43+00:00

Add support for the DISCARD file operation. Discard punches a hole
in a file in the provided range. Block de-allocation is implemented
via fallocate() (as requested via fuse and passed on to the brick
fs) but a separate fop is created within gluster to emphasize the
fact that discard changes file data (the discarded region is
replaced with zeroes) and must invalidate caches where appropriate.

BUG: 963678
Change-Id: I34633a0bfff2187afeab4292a15f3cc9adf261af
Signed-off-by: Brian Foster 
Reviewed-on: http://review.gluster.org/5090
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

gluster: add fallocate fop support

2013-06-13T21:37:21+00:00

Implement support for the fallocate file operation. fallocate
allocates blocks for a particular inode such that future writes
to the associated region of the file are guaranteed not to fail
with ENOSPC.

This patch adds fallocate support to the following areas:

	- libglusterfs
	- mount/fuse
	- io-stats
	- performance/md-cache,open-behind
	- quota
	- cluster/afr,dht,stripe
	- rpc/xdr
	- protocol/client,server
	- io-threads
	- marker
	- storage/posix
	- libgfapi

BUG: 949242
Change-Id: Ice8e61351f9d6115c5df68768bc844abbf0ce8bd
Signed-off-by: Brian Foster 
Reviewed-on: http://review.gluster.org/4969
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

features/marker: log error when unlinking timestamp file

2013-03-21T11:21:45+00:00

... so it's easy to figure out errno caused it. As of now
it's only due to ENOSPC. Logging is done in the error handling
routine, so any further changes that require unlinking of the
timestamp file due to some error condition(s) are logged.

Change-Id: Ia59338e2e32b2adbbd1d56aa260018270f1abae9
BUG: 853911
Signed-off-by: Venky Shankar 
Reviewed-on: http://review.gluster.org/4649
Reviewed-by: Csaba Henk 
Reviewed-by: Amar Tumballi 
Reviewed-by: Vijay Bellur 
Tested-by: Gluster Build System

Use proper libtool option -avoid-version instead of bogus -avoidversion

2013-02-07T23:12:56+00:00

Change-Id: I1c9541058c7d07786539a3266ca125a6a15287d8
BUG: 859835
Signed-off-by: Anand Avati 
Original-author: Kacper Kowalik (Xarthisius) 
Signed-off-by: Kacper Kowalik (Xarthisius) 
Reviewed-on: http://review.gluster.org/3967
Tested-by: Gluster Build System

build: split CPPFLAGS from CFLAGS

2012-10-03T19:26:45+00:00

Automake provides a separate variable for preprocessor flags
(*_CPPFLAGS). They are already uses in a few places, so make it
consistent and use it everywhere. Note that cflags obtained from
pkg-config often are cppflags, which is why LIBXML2_CFLAGS moves with
into AM_CPPFLAGS, for example.

Change-Id: I15feed1d18b2ca497371271c4b5876d5ec6289dd
BUG: 862082
Original-author: Jan Engelhardt 
Signed-off-by: Jan Engelhardt 
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4029
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

build: remove useless explicit -fPIC -shared from

2012-10-03T19:24:59+00:00

 CFLAGS

libtool will automatically add "-fPIC" to the compiler command line as
needed, so there is no need to specify it separately.

"-shared" is normally a linker flag and has an odd effect when used with
libtool --mode=compile, namely that it inhibits production of static
objects. For that however, using AC_DISABLE_STATIC is a lot simpler.

Change-Id: Ic4cba0fad18ffd985cf07f8d6951a976ae59a48f
BUG: 862082
Original-author: Jan Engelhardt 
Signed-off-by: Jan Engelhardt 
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4027
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

build: remove -nostartfiles flag

2012-10-02T20:11:43+00:00

The "-nostartfiles" is a discouraged option and is documented to
potentially result in undesired behavior. Since I see no reason why it
should be in glusterfs, remove it.

Change-Id: I56f2b08874516ebad91447b2583ca2fb776bb7ab
BUG: 862082
Original-author: Jan Engelhardt 
Signed-off-by: Jan Engelhardt 
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4018
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati