Problem: When trying to convert a plain distribute volume to replica-3 or arbiter type it is failing with ENOTCONN error as the lookup on the root will fail as there is no quorum. Fix: Allow lookup on root if it is coming from the ADD_REPLICA_MOUNT which is used while adding bricks to a volume. It will try to set the pending xattrs for the newly added bricks to allow the heal to happen in the right direction and avoid data loss scenarios. Note: This fix will solve the problem of type conversion only in the case where the volume was mounted at least once. The conversion of non mounted volumes will still fail since the dht selfheal tries to set the directory layout will fail as they do that with the PID GF_CLIENT_PID_NO_ROOT_SQUASH set in the frame->root. Change-Id: Ic511939981dad118cc946754341318b164954b3b fixes: bz#1655854 Signed-off-by: karthik-us <ksubrahm@redhat.com>
2 domain locking + xattrop for write-txn failures: -------------------------------------------------- - A post-op wound on TA takes AFR_TA_DOM_NOTIFY range lock and AFR_TA_DOM_MODIFY full lock, does xattrop on TA and releases AFR_TA_DOM_MODIFY lock and stores in-memory which brick is bad. - All further write txn failures are handled based on this in-memory value without querying the TA. - When shd heals the files, it does so by requesting full lock on AFR_TA_DOM_NOTIFY domain. Client uses this as a cue (via upcall), releases AFR_TA_DOM_NOTIFY range lock and invalidates its in-memory notion of which brick is bad. The next write txn failure is wound on TA to again update the in-memory state. - Any incomplete write txns before the AFR_TA_DOM_NOTIFY upcall release request is got is completed before the lock is released. - Any write txns got after the release request are maintained in a ta_waitq. - After the release is complete, the ta_waitq elements are spliced to a separate queue which is then processed one by one. - For fops that come in parallel when the in-memory bad brick is still unknown, only one is wound to TA on wire. The other ones are maintained in a ta_onwireq which is then processed after we get the response from TA. Change-Id: I32c7b61a61776663601ab0040e2f0767eca1fd64 updates: bz#1579788 Signed-off-by: Ravishankar N <ravishankar@redhat.com> Signed-off-by: Ashish Pandey <aspandey@redhat.com>
Change-Id: I6f5d8140a06f3c1b2d196849299f8d483028d33b
...that can be used by client and self-heal daemon, namely: afr_ta_post_op_lock() afr_ta_post_op_unlock() Note: These are not yet consumed. They will be used in the write txn changes patch which will introduce 2 domain locking. updates: bz#1579788 Change-Id: I636d50f8fde00736665060e8f9ee4510d5f38795 Signed-off-by: Ravishankar N <ravishankar@redhat.com>
1. Create thin arbiter index file during mount. 2. Set pending marker in thin arbiter id file in case of failure. Change-Id: I269eb8d069f0323f1fc616175e5e5eb7b91d5f82 updates: #352 Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Updates: #363 This new value (3) will try to wind read requests to the child of AFR having the least amount of pending requests in its queue. Change-Id: If6bda2aac9bf7aec3fc39622f78659313c4b6508 Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Problem: 1) Afr's eager-lock only works for data transactions. 2) When there are conflicting writes, write with conflicting region initiates unlock of eager-lock leading to extra pre-ops and post-ops on the file. When eager-lock goes off, it leads to extra fsyncs for random-write workload in afr. Solution (that is modeled after EC): In EC, when there is a conflicting write, it waits for the current write to complete before it winds the conflicted write. This leads to better utilization of network and disk, because we will not be doing extra xattrops and FSYNCs and inodelk/unlock. Moved fd based counters to inode based counters. I tried to model the solution based on EC's locking, but it is not similar to AFR because we had to keep backward compatibility. Lifecycle of lock: ================== First transaction is added to inode->owners list and an inodelk will be sent on the wire. All the next transactions will be put in inode->waiters list until the first transaction completes inodelk and [f]xattrop completely. Once [f]xattrop also completes, all the requests in the inode->waiters list are checked if it conflict with any of the existing locks which are in inode->owners list and if not are added to inode->owners list and resumed with doing transaction. When these transactions complete fop phase they will be moved to inode->post_op list and resume the transactions that were paused because of conflicts. Post-op and unlock will not be issued on the wire until that is the last transaction on that inode. Last transaction when it has to perform post-op can choose to sleep for deyed-post-op-secs value. During that time if any other transaction comes, it will wake up the sleeping transaction and takes over the ownership of the lock and the cycle continues. If the dealyed-post-op-secs expire, then the timer thread will wakeup the sleeping transaction and it will set lock->release to true and starts doing post-op and then unlock. During this time if any other transactions come, they will be put in inode->frozen list. Once the previous unlock comes it will move the frozen list to waiters list and moves the first element from this waiters-list to owners-list and attempts the lock and the cycle continues. This is the general idea. There is logic at the time of dealying and at the time of new transaction or in flush fop to wakeup existing sleeping transactions or choosing whether to delay a transaction etc, which is subjected to change based on future enhancements etc. Fixes: #418 BUG: 1549606 Change-Id: I88b570bbcf332a27c82d2767dfa82472f60055dc Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Removed 1) afr-v1 self-heal locks related code which is not used anymore 2) transaction has some data types that are not needed, so removed them 3) Never used lock tracing available in afr as gluster's network tracing does the job. So removed that as well. 4) Changelog is always enabled and afr is always used with locks, so __changelog_enabled, afr_lock_server_count etc functions can be deleted. 5) transaction.fop/done/resume always call the same functions, so no need to have these variables. BUG: 1549606 Change-Id: I370c146fec2892d40e674d232a5d7256e003c7f1 Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
We are not seeing much improvement with this change. So removing the feature so that it doesn't need to be maintained anymore. Fixes: #414 Change-Id: Ic7969b151544daf2547bd262a9fa03f575626411 Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Problem: If quorum is not met in fop cbk, arbiter sends an ENOTCONN error to the upper xlators. In a VM workload with sharding enabled, this was leading to the VM pausing when replace-brick was performed as described in the BZ. Fix: Move the fop cbk arbitration logic to afr_handle_quorum() because in normal replica volumes, that is the function that has the quorum and errno checks in the fop cbk path before doing a post-op. Thanks to Pranith for suggesting this approach. Change-Id: Ie6315db30c5e36326b71b90a01da824109e86796 BUG: 1449610 Signed-off-by: Ravishankar N <ravishankar@redhat.com> Reviewed-on: https://review.gluster.org/17235 Smoke: Gluster Build System <jenkins@build.gluster.org> Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> CentOS-regression: Gluster Build System <jenkins@build.gluster.org>