This wait is to make sure that backup workers are already saving mutations so
that no mutations are missed. The idea is that the CLI sets a "backupStartedKey"
in the database and waits for allWorkerStarted() key of the backup to be set.
Backup workers monitor the changes to the "backupStartedKey" and start logging
mutations. Additionally, backup worker for Tag(-2,0) monitors all other workers
have started (checking their saved progress version is larger than the backup's
start version), and then sets the allWorkerStarted() key for the backup.
If there are unfinished ranges in the old epochs, the new master will recruit
backup workers responsible for finishing these ranges. These workers remains in
the cluster until the next epoch, when it will remove itself.
- Make sure the disabled data distribution won't be accidentally enabled by the 'maintenance' command
- Make sure the status json reflects the status of DD accordingly
- Make sure the CLI can play with the new DD states correctly, i.e. print out warns when necessary
- Use pre-existing 'healthZone' key and write a special value to it in order to disable DD for all storage server failures
- Use a new system key 'rebalanceDDIgnored' key to disable/enable DD for all rebalance reasons(MountainChopper and ValleyFiller)
Kicked off two 200K correctness and showed no related errors.
1) Should recruit only configured number of roles;
2) Should never register a restore master interface as a restore worker (loader or applier) interface.
fdbcli has a new command 'consistencycheck' to disable/re-enable consistency check.
cluster_healthy metric in status becomes false if consistencycheck is disabled.
RestoreMaster may not receive all acks. for the last command, i.e., finishRestore,
because RestoreLoaders and RestoreAppliers exit immediately after sending the ack.
If the ack is lost, it will not be resent.
This commit also removes some unneeded code.
This commit passes 50k random tests without errors.
1) Use the runRYWTransaction for simple DB access
2) Replace some printf with TraceEvent
3) Remove printf not used in debugging
4) Avoid wait inside the condition in loop-choose-when for
the core routine of restore worker, loader and applier.
5) Rename Restore.actor.cpp to RestoreWorker.actor.cpp since
the file only has functionalities related to restore worker.
Passed correctness test
Add a NotifiedVersion into an applier data which represents
the smallest version the applier is at.
When a loader sends mutation vector to appliers, it sends
the request that contains prevVersion and commitVersion.
This commits also put actor into an actorCollector for
loop-choose-when situation.
The current code uses one restore interface to handle the work
for all restore roles, i.e., master, loader and applier.
This makes it harder to review or maintain or scale.
This commit split the restore into multiple roles by mimicing FDB
transaction system:
1) It uses a RestoreWorker as the process to host restore roles;
This commit assumes one restore role per RestoreWorker; but
it should be easy to extend to support multiple roles per RestoreWorker;
2) It creates 3 restore roles:
RestoreMaster: Coordinate the restore process and send commands to the other two roles;
RestoreLoader: Parse backup files to mutations and send mutations to appliers;
RestoreApplier: Sort received mutations and apply them to DB in order.
Compilable version. To be tested in correctness.
Add .h and .cpp files for RestoreLoader and RestoreApplier roles.
We will split the code for each restore role into a separate file.
This commit also fixes the bug in including RestoreCommon.actor.h, and
remove the unused code.