glusterfs.git/xlators/protocol/client/src, branch v3.5.0

mgmt/glusterd: Improve the description in volume set help output

2014-01-29T06:33:30+00:00

Change-Id: I785648970f53033a69922c23110b5eea9e47feb3
BUG: 1046030
Signed-off-by: Varun Shastry 
Reviewed-on: http://review.gluster.org/6573
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur 
Reviewed-on: http://review.gluster.org/6837

protocol: pass the size of the data in the WRITE on-wire FOP

2014-01-24T09:24:50+00:00

Capturing GlusterFS traffic with tcpdump and displaying it in Wireshark
shows that the size of all WRITEs are 0 bytes. It seems that the
attribute is not used, and the size is calculated an other way.

Even if the size attribute is not used (yet), it should be set correctly
to prevent confusing while debugging network traffic with Wireshark or
other tools.

Note that the on-wire format is not being changed with this patch. The
size is already part of the structure that is exchanged between the
client and server.

Change-Id: I4a1729a8e154a6fed4f8baa10ef3009d4df040cf
Master-Change-Id: I9d67fe17bf203672116dea4948328e2af4004677
Master-Reviewed-on: http://review.gluster.org/6766
BUG: 1057264
Signed-off-by: Niels de Vos 
Reviewed-on: http://review.gluster.org/6768
Tested-by: Gluster Build System 
Reviewed-by: Vikhyat Umrao

protocol/client: handle network disconnect/reconnect properly

2013-12-03T19:35:32+00:00

if client/server state versions match, we still need to notify
parent xlators of reconnection (CHILD_UP) because they were
notified of CHILD_DOWN at the time of disconnection.

Change-Id: I36c4bde6d8c3db9cb0c48eeb10663b56897c932e
BUG: 1037267
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6398
Tested-by: Gluster Build System 
Reviewed-by: Krishnan Parthasarathi

core: fix errno for non-existent GFID

2013-11-26T18:29:23+00:00

When clients refer to a GFID which does not exist, the errno to
be returned in ESTALE (and not ENOENT). Even though ENOENT might
look "proper" most of the time, as the application eventually expects
ENOENT even if a parent directory does not exist, not returning
ESTALE results in resolvers (FUSE and GFAPI) to not retry resolution
in uncached mode. This can result in spurious ENOENTs during
concurrent path modification operations.

Change-Id: I7a06ea6d6a191739f2e9c6e333a1969615e05936
BUG: 1032894
Signed-off-by: Anand Avati 
Reviewed-on: http://review.gluster.org/6318
Tested-by: Gluster Build System 
Reviewed-by: Amar Tumballi 
Reviewed-by: Brian Foster 
Reviewed-by: Vijay Bellur

Fixes for ZF reported by coverity

2013-11-19T17:57:37+00:00

BUG: 1028673
Change-Id: I7c75738cca22c81c5629d579ef5bea24000e622e
Signed-off-by: M. Mohan Kumar 
Reviewed-on: http://review.gluster.org/6291
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

zerofill: Change the type of len argument of glfs_zerofill() to off_t

2013-11-15T07:29:48+00:00

glfs_zerofill() can be potentially called to zero-out entire file and
hence allow for bigger value of length parameter.

Change-Id: I75f1d11af298915049a3f3a7cb3890a2d72fca63
BUG: 1028673
Signed-off-by: Bharata B Rao 
Reviewed-on: http://review.gluster.org/6266
Tested-by: Gluster Build System 
Reviewed-by: M. Mohan Kumar 
Tested-by: M. Mohan Kumar 
Reviewed-by: Anand Avati

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

libglusterfs: Add monotonic clocking counter for timer thread

2013-10-15T07:14:57+00:00

gettimeofday() returns the current wall clock time and timezone.
Using these functions in order to measure the passage of time
(how long an operation took) therefore seems like a no-brainer.

This time suffer's from some limitations:

a. They have a low resolution: “High-performance” timing by
definition, requires clock resolutions into the microseconds
or better.

b. They can jump forwards and backwards in time: Computer
clocks all tick at slightly different rates, which causes
the time to drift. Most systems have NTP enabled which
periodically adjusts the system clock to keep them in sync
with “actual” time. The adjustment can cause the clock to
suddenly jump forward (artificially inflating your timing
numbers) or jump backwards (causing your timing calculations
to go negative or hugely positive). In such cases timer
thread could go into an infinite loop.

From 'man gettimeofday':
----------
..
..
The time returned by gettimeofday() is affected by discontinuous
jumps in the system time (e.g., if the system administrator manually
changes the system time).  If you need a monotonically increasing
clock, see clock_gettime(2).
..
..
----------

Rationale:

For calculating interval timing for Timer thread, all that’s
needed should be clock as a simple counter that increments
at a stable rate.

This is necessary to avoid the jumps which are caused by using
"wall time", this counter must be monotonic that can never
“tick” backwards, ever.

Change-Id: I701d31e71a85a73d21a6c5cd15583e7a5a645eeb
BUG: 1017993
Signed-off-by: Harshavardhana 
Reviewed-on: http://review.gluster.org/6070
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

protocol/rpc: move latest added procedures to the end of the array

2013-06-17T16:34:56+00:00

While looking at the newly introduced procedures FALLOCATE and DISCARD,
it seems that these were added with already existing procedure numbers.
This makes the protocol incompatible with existing roll-outs.

It is very confusing when new procedures are added somewhere in the
middle of the array. This will cause the number of existing procedures
to change. It is much preferred to add new procedures at the end of the
array. This changes not only corrects the enum that generates the
procedure numbers, but also the ordering in the client and server
fops-array for clarity.

Correcting this greatly simplifies adding support for these new
procedures in Wireshark and will prevent confusion to the people reading
network traces (with or without Wireshark).

Change-Id: Ib9e7978531d016c7230d756b855cb94cb0793b0f
BUG: 974976
Signed-off-by: Niels de Vos 
Reviewed-on: http://review.gluster.org/5215
Tested-by: Gluster Build System 
Reviewed-by: Brian Foster 
Reviewed-by: Anand Avati

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