The backup container can figure out if partitioned logs are used by looking at
mutation logs, thus consolidating the API to a single describeBackup() as
before.
Partitioned logs can have strict subset version ranges, which was not properly
handled -- we used to assume overlapping only happens for the same begin
version.
If a log file's progress is not saved, a new log file will be generated
with the same begin version. Then we can have a file that contains a subset
of contents in another log file. During restore, we should filter out files
that their contents are subset of other files.
For partitioned logs, computing continuous log end version from min logs begin
version. Old backup test keeps using describeBackup() to be correctness clean.
Rename partitioned log file so that the last number is block size.
In parallel restore, use new getPartitionedRestoreSet() to get a set containing
partitioned mutation logs. The loader uses a new parser to extract mutations
from partitioned logs.
TODO: fix unable to restore 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
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.
In fdb 6.0.15, backup container is changed on how to organize the backup data.
The backup made by fdb >6.0.15 has to be restored with fdb > 6.0.15.
Merge with master so that the fast restore uses fdb > 6.0.15
The global variables for a process in real mode are separate across processes in real mode, BUT
they are NOT separate in simulation mode.
The workers in different processes can still access the global variables,
which makes one worker overwrite another work's global variable value.
To solve this problem, which happens in other FDB code as well,
we allocate the global variable in a heap and pass the pointers across functions,
as what DataDistribution.actor does.
The other approach is to create two code path: one for real mode and the other for simulator,
as the g_simulator does to create the process context for each simulated process
FDB Formatster