Because retore roles run as workload in simulation,
they do not know when DB is destroyed by the backup and restore test workload.
So if DB is destroyed earlier than restore master unlocks DB, which is rare,
restore master should abort the unlocking DB step.
atomicOp has an amplified performance overhead to the cluster,
for example, an ADD operation can be small, but SS has to load
the value to do the operation and the value can be large.
1) Do not keep restore role data (e.g., masterData) in restore worker;
2) Change function parameter list by only passing in the needed variables in role data;
3) Remove unneccessary files vector from masterData;
4) Change typos in comments and some functions name.
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) Remove global map to buffer the parsed mutations on loader.
Use local map instead to increase parallelism.
2) Use std::map<LoadingParam, Future<Void>> to hold the actor
that parse a backup file and to de-duplicate requests.
3) Remove unused code.
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.