glusterfs.git/xlators/cluster/dht/src/nufa.c, branch v4.0dev1

dht: At places needed use STACK_WIND_COOKIE

2017-01-09T18:37:02+00:00

Issue:
frame has a void * cookie pointer.
In case of STACK_WIND_COOKIE frame->cookie is assigned
to what is sent by the caller.
In case of STACK_WIND frame->cookie is assigned to point
point to the frame itself.

For ease of coding, at many places, the cookie in the cbk
is used to get the pointer to the next xl. This is
inconsistent when STACK_WIND_TAIL comes into picture.

Eg: dht_setxattr () {
    for (i = 0 ; i < conf->subvolume_cnt ; i++) {
       STACK_WIND (..dht_checking_pathinfo_cbk,
                   conf->subvolumes[i] ..);
    }

    dht_checking_pathinfo_cbk (...void *cookie...) {
        prev = cookie;
        ...
        for (i = 0; i < conf->subvolume_cnt; i++) {
            if (conf->subvolumes[i] == prev->this) {
                 ...
            }
        }
    }

    Consider the below graph:
    dht (parent)
    readdir-ahead  => Doesn't define setxattr and uses STACK_WIND_TAIL
    protocol-client

    With this graph, when dht_checking_pathinfo_cbk is called,
    cookie will have frame pointing to protocol-client.
    i.e. prev->this will be protocol-client. But dht was expecting
    it to be readdir-ahead as it has stored in conf->subvolumes[i]

Solution:
    Hence, as a thumb rule, if cbk is using cookie, then we explicitly
    call STACK_WIND_COOKIE.

Change-Id: I83aea1e24c809c5a91a0db7283e908e125471bd4
BUG: 1401812
Signed-off-by: Poornima G 
Reviewed-on: http://review.gluster.org/16039
Reviewed-by: Raghavendra G 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

dht: Adding log messages to the new logging framework

2015-06-24T05:15:10+00:00

Change-Id: Ib3bb61c5223f409c23c68100f3fe884918d2dc3f
BUG: 1194640
Signed-off-by: arao 
Reviewed-on: http://review.gluster.org/10021
Reviewed-by: N Balachandran 
Reviewed-by: Joseph Fernandes
Tested-by: Joseph Fernandes
Reviewed-by: Dan Lambright 
Reviewed-by: Raghavendra G 
Tested-by: Raghavendra G

build: do not #include "config.h" in each file

2015-05-29T12:43:17+00:00

Instead of including config.h in each file, and have the additional
config.h included from the compiler commandline (-include option).

When a .c file tests for a certain #define, and config.h was not
included, incorrect assumtions were made. With this change, it can not
happen again.

BUG: 1222319
Change-Id: I4f9097b8740b81ecfe8b218d52ca50361f74cb64
Signed-off-by: Niels de Vos 
Reviewed-on: http://review.gluster.org/10808
Tested-by: Gluster Build System 
Tested-by: NetBSD Build System
Reviewed-by: Kaleb KEITHLEY 
Reviewed-by: Pranith Kumar Karampuri

cluster/dht: Add tier translator.

2015-03-21T16:50:29+00:00

The tier translator shares most of DHT's code. It differs in how
subvolumes are chosen for I/Os, and how file migration (cache promotion
and demotion) is managed. That different functionality is split to either
DHT or tier logic according to the "tier_methods" structure.

A cache promotion and demotion thread is created in a manner
similar to the rebalance daemon. The thread operates a timing
wheel which periodically checks for promotion and demotion candidates
(files). Candidates are queued and then migrated. Candidates must exist on
the same node as the daemon and meet other critera per caching policies.

This patch has two authors (Dan Lambright and Joseph Fernandes). Dan
did the DHT changes and Joe wrote the cache policies. The fix depends on
DHT readidr changes and the database library which have been submitted
separately.  Header files in libglusterfs/src/gfdb should be reviewed in
patch 9683.

For more background and design see the feature page [1].

[1]
http://www.gluster.org/community/documentation/index.php/Features/data-classification

Change-Id: Icc26c517ccecf5c42aef039f5b9c6f7afe83e46c
BUG: 1194753
Signed-off-by: Dan Lambright 
Reviewed-on: http://review.gluster.org/9724
Reviewed-by: Vijay Bellur 
Tested-by: Vijay Bellur

Cluster/DHT: New logging framework

2014-06-16T13:25:51+00:00

Moved all relevant DHT gf_log calls to the new logging
framework.

Change-Id: I3af3cfe0416e332774a6c4ff6a091d006c400af2
BUG: 1075611
Signed-off-by: Nithya Balachandran 
Reviewed-on: http://review.gluster.org/7929
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

cluster/dht: Allow non-local clients to function with nufa volumes.

2013-07-29T13:27:47+00:00

nufa fails to init if a local brick is not found as of today.
With this patch, if a local brick is not found, nufa switches
over to dht mode of operations.

Change-Id: I50ac1af37621b1e776c8c00a772b8e3dfb3691df
BUG: 980838
Signed-off-by: Vijay Bellur 
Reviewed-on: http://review.gluster.org/5414
Reviewed-by: Jeff Darcy 
Tested-by: Gluster Build System

cluster/dht: Ignore subvols with error in min-free-disk/inodes

2013-07-10T08:56:38+00:00

Currently when selecting a alternative subvolume when hashed
subvol has exceeded min-free-disk/inodes, we do not check if
layouts have errors (including decommissioning). This leads
to data being written to those subvolumes, and in case of
decommissioning, will lead to data loss.

Change-Id: Ie0c6cf4a29d7c53d8a6d8a8c1bd595cf58a0012a
BUG: 982919
Signed-off-by: shishir gowda 
Reviewed-on: http://review.gluster.org/5299
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

nufa: allow subvols with fanout > 1

2013-07-04T14:30:00+00:00

Previously, nufa wouldn't work on volume topologies such as
distribute-replicate or distribute-stripe.

Change-Id: Ia89ed4412a00601022c1fc94f046056ce4820fe8
BUG: 980838
Signed-off-by: Krishnan Parthasarathi 
Reviewed-on: http://review.gluster.org/5262
Tested-by: Gluster Build System 
Reviewed-by: Vijay Bellur

dht: make nufa/switch call dht's init/fini

2013-04-03T22:16:24+00:00

These functions keep changing as new functionality is added, so copying
and pasting the code is not a good solution.  This way ensures that all
fields get initialized properly no matter how much new stuff we throw in.

Change-Id: I9e9b043d2d305d31e80cf5689465555b70312756
BUG: 924488
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4710
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati

dht: make DHT xattr names configurable

2013-03-21T22:04:31+00:00

This is necessary to support "DHT over DHT" configurations, so that the
upper and lower instances of DHT don't step all over each other.  Why
would we even consider such a thing?  Because it gives us the ability to
do data tiering and rack-aware placement, either by themselves or as
complements to other functionality such as erasure codes or
deduplication which save space but cost performance.  By setting up the
top-level DHT to place data into one of several lower-level DHT pools
based on policy instead of pure elastic hashing, we get better
performance for 90% of accesses and better storage efficiency for 90% of
data, all for relatively low effort.

Change-Id: I72e65c29edfc80babf39f7a2a00090f4588c4070
BUG: 924265
Signed-off-by: Jeff Darcy 
Reviewed-on: http://review.gluster.org/4694
Tested-by: Gluster Build System 
Reviewed-by: Anand Avati