glusterfs.git/xlators/cluster/ec/src/ec-helpers.c, branch v3.10.4

cluster/ec: Don't trigger data/metadata heal on Lookups

2017-02-27T15:34:08+00:00

Problem-1
If Lookup which doesn't take any locks observes version mismatch it can't be
trusted. If we launch a heal based on this information it will lead to
self-heals which will affect I/O performance in the cases where Lookup is
wrong. Considering self-heal-daemon and operations on the inode from client
which take locks can still trigger heal we can choose to not attempt a heal on
Lookup.

Problem-2:
Fixed spurious failure of
tests/bitrot/bug-1373520.t
For the issues above, what was happening was that ec_heal_inspect()
is preventing 'name' heal to happen

Problem-3:
tests/basic/ec/ec-background-heals.t
To be honest I don't know what the problem was, while fixing
the 2 problems above, I made some changes to ec_heal_inspect() and
ec_need_heal() after which when I tried to recreate the spurious
failure it just didn't happen even after a long time.

 >BUG: 1414287
 >Signed-off-by: Pranith Kumar K 
 >Change-Id: Ife2535e1d0b267712973673f6d474e288f3c6834
 >Reviewed-on: https://review.gluster.org/16468
 >Smoke: Gluster Build System 
 >NetBSD-regression: NetBSD Build System 
 >Reviewed-by: Xavier Hernandez 
 >CentOS-regression: Gluster Build System 
 >Reviewed-by: Ashish Pandey 

BUG: 1419824
Change-Id: I340b48cd416b07890bf3a5427562f5e3f88a481f
Signed-off-by: Pranith Kumar K 
Reviewed-on: https://review.gluster.org/16765
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Xavier Hernandez 
Smoke: Gluster Build System

cluster/ec: Fix lk-owner set race in ec_unlock

2016-12-13T15:24:51+00:00

Problem:
Rename does two locks. There is a case where when it tries to unlock it sends
xattrop of the directory with new version, callback of these two xattrops can
be picked up by two separate epoll threads. Both of them will try to set the
lk-owner for unlock in parallel on the same frame so one of these unlocks will
fail because the lk-owner doesn't match.

Fix:
Specify the lk-owner which will be set on inodelk frame which will not be over
written by any other thread/operation.

BUG: 1402710
Change-Id: I666ffc931440dc5253d72df666efe0ef1d73f99a
Signed-off-by: Pranith Kumar K 
Reviewed-on: http://review.gluster.org/16074
Reviewed-by: Xavier Hernandez 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System

cluster/ec: Add support for hardware acceleration

2016-09-08T17:08:25+00:00

This patch implements functionalities for fast encoding/decoding
using hardware support. Currently optimized x86_64, SSE and AVX is
added.

Additionally this patch implements a caching mecanism for inverse
matrices to reduce computation time, as well as a new method for
computing the inverse that takes quadratic time instead of cubic.

Finally some unnecessary memory copies have been eliminated to
further increase performance.

Change-Id: I26c75f26fb4201bd22b51335448ea4357235065a
BUG: 1289922
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/12837
Tested-by: Pranith Kumar Karampuri 
Smoke: Gluster Build System 
NetBSD-regression: NetBSD Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri

cluster/afr: Prevent split-brain when bricks are brought off and on in cyclic order

2016-08-22T09:38:36+00:00

When the bricks are brought offline and then online in cyclic
order while writes are in progress on a file, thanks to inode
refresh in write txns, AFR will mostly fail the write attempt
when the only good copy is offline. However, there is still a
remote possibility that the file will run into split-brain if
the brick that has the lone good copy goes offline *after* the
inode refresh but *before* the write txn completes (I call it
in-flight split-brain in the patch for ease of reference),
requiring intervention from admin to resolve the split-brain
before the IO can resume normally on the file. To get around this,
the patch does the following things:
i) retains the dirty xattrs on the file
ii) avoids marking the last of the good copies as bad (or accused)
    in case it is the one to go down during the course of a write.
iii) fails that particular write with the appropriate errno.

This way, we still have one good copy left despite the split-brain situation
which when it is back online, will be chosen as source to do the heal.

Change-Id: I9ca634b026ac830b172bac076437cc3bf1ae7d8a
BUG: 1363721
Signed-off-by: Krutika Dhananjay 
Reviewed-on: http://review.gluster.org/15080
Tested-by: Pranith Kumar Karampuri 
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Ravishankar N 
Reviewed-by: Oleksandr Natalenko 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Pranith Kumar Karampuri

cluster/ec: Fix invalid config check for directories

2016-03-01T07:56:41+00:00

The trusted.ec.config xattr is not defined for directories. However
sometimes it could be requested because the inode type of a directory
can temporarily be IA_INVAL.

Requesting such xattr using the xattrop fop when it doesn't exist,
returns a config value full of 0's, which is invalid and caused some
fops to fail.

This patch filters out this case by ignoring config xattr == 0.

Change-Id: Ied51c35b313ea8c3eeae27812f9bae61d3808e92
BUG: 1293223
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/13446
Smoke: Gluster Build System 
CentOS-regression: Gluster Build System 
Reviewed-by: Ashish Pandey 
NetBSD-regression: NetBSD Build System 
Reviewed-by: Jeff Darcy

cluster/ec: Fix tracking of good bricks

2015-08-06T17:12:22+00:00

The bitmask of good and bad bricks was kept in the context of the
corresponding inode or fd. This was problematic when an external
process (another client or the self-heal process) did heal the
bricks but no one changed the bitmaks of other clients.

This patch removes the bitmask stored in the context and calculates
which bricks are healthy after locking them and doing the initial
xattrop. After that, it's updated using the result of each fop.

Change-Id: I225e31cd219a12af4ca58871d8a4bb6f742b223c
BUG: 1236065
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/11844
Tested-by: NetBSD Build System 
Tested-by: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri

cluster/ec: Minimize usage of EIO error

2015-07-28T11:12:17+00:00

Change-Id: I82e245615419c2006a2d1b5e94ff0908d2f5e891
BUG: 1245276
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/11741
Tested-by: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri 
Tested-by: NetBSD Build System

dict: dict_set_bin() should never free the pointer on error

2015-07-24T15:09:08+00:00

dict_set_bin() is handling the pointer that it passed inconsistently.
Depending on the errors that can occur, the pointer passed to the dict
can be free'd, but there is no guarantee.

It is cleaner to have the caller free the pointer that allocated it and
dict_set_bin() returned an error. When dict_set_bin() returned success,
the given pointer will be free'd when dict_unref() calls data_destroy().

Many callers of dict_set_bin() already take care of free'ing the pointer
on error. The ones that did not, are corrected with this change too.

Change-Id: I39a4f7ebc0cae6d403baba99307d7ce408f25966
BUG: 1242280
Signed-off-by: Niels de Vos 
Reviewed-on: http://review.gluster.org/11638
Tested-by: Gluster Build System 
Reviewed-by: jiffin tony Thottan 
Reviewed-by: Raghavendra G 
Tested-by: NetBSD Build System

ec: Porting messages to new logging framework

2015-06-26T15:51:59+00:00

Change-Id: Ia05ae750a245a37d48978e5f37b52f4fb0507a8c
BUG: 1194640
Signed-off-by: Nandaja Varma 
Reviewed-on: http://review.gluster.org/10465
Tested-by: NetBSD Build System 
Reviewed-by: Xavier Hernandez

cluster/ec: Forced unlock when lock contention is detected

2015-05-27T10:25:47+00:00

EC uses an eager lock mechanism to optimize multiple read/write
requests on the same entry or inode. This increases performance
but can have adverse results when other clients try to access the
same entry/inode.

To solve this, this patch adds a functionality to detect when this
happens and force an earlier release to not block other clients.

The method consists on requesting GF_GLUSTERFS_INODELK_COUNT and
GF_GLUSTERFS_ENTRYLK_COUNT for all fops that take a lock. When this
count is greater than one, the lock is marked to be released. All
fops already waiting for this lock will be executed normally before
releasing the lock, but new requests that also require it will be
blocked and restarted after the lock has been released and reacquired
again.

Another problem was that some operations did correctly lock the
parent of an entry when needed, but got the size and version xattrs
from the entry instead of the parent.

This patch solves this problem by binding all queries of size and
version to each lock and replacing all entrylk calls by inodelk ones
to remove concurrent updates on directory metadata.  This also allows
rename to correctly update source and destination directories.

Change-Id: I2df0b22bc6f407d49f3cbf0733b0720015bacfbd
BUG: 1165041
Signed-off-by: Xavier Hernandez 
Reviewed-on: http://review.gluster.org/10852
Tested-by: NetBSD Build System
Tested-by: Gluster Build System 
Reviewed-by: Pranith Kumar Karampuri