LZ4 compresses data faster than gzip but at a lower ratio. This can be a good tradeoff in certain scenarios.
Note that setting compress-type=lz4 will make new backups and archive incompatible (unrestorable) with prior versions of pgBackRest.
This was the interface between Perl and C introduced in 36a5349b but since f0ef73db has only been used by the Perl integration tests. This is expensive code to maintain just for testing.
The main dependency was the interface to storage, no matter where it was located, e.g. S3. Replace this with the new-introduced repo commands (d3c83453) that allow access to repo storage via the command line.
The other dependency was on various cfgOption* functions and CFGOPT_ constants that were convenient but not necessary. Replace these with hard-coded strings in most places and create new constants for commonly used values.
Remove all auto-generated Perl code. This means that the error list will no longer be maintained automatically so copy used errors to Common::Exception.pm. This file will need to be maintained manually going forward but there is not likely to be much churn as the Perl integration tests are being retired.
Update test.pl and related code to remove LibC builds.
Ding, dong, LibC is dead.
Add compress-type option and deprecate compress option. Since the compress option is boolean it won't work with multiple compression types. Add logic to cfgLoadUpdateOption() to update compress-type if it is not set directly. The compress option should no longer be referenced outside the cfgLoadUpdateOption() function.
Add common/compress/helper module to contain interface functions that work with multiple compression types. Code outside this module should no longer call specific compression drivers, though it may be OK to reference a specific compression type using the new interface (e.g., saving backup history files in gz format).
Unit tests only test compression using the gz format because other formats may not be available in all builds. It is the job of integration tests to exercise all compression types.
Additional compression types will be added in future commits.
Previously the mock integration tests would be skipped for VMs other than the standard four used in CI. Now VMs outside the standard four will run the same tests as VM4 (currently U18).
Maintaining the storage layer/drivers in two languages is burdensome. Since the integration tests require the Perl storage layer/drivers we'll need them even after the core code is migrated to C. Create an interface layer so the Perl code can be removed and new storage drivers/features introduced without adding Perl equivalents.
The goal is to move the integration tests to C so this interface will eventually be removed. That being the case, the interface was designed for maximum compatibility to ease the transition. The result looks a bit hacky but we'll improve it as needed until it can be retired.
This new implementation should behave exactly like the old Perl code with the exception of updated log messages.
Remove as much of the Perl code as possible without breaking other commands.
The same test configurations are run on all four test VMs, which seems a real waste of resources.
Vary the tests per VM to increase coverage while reducing the total number of tests. Be sure to include each major feature (remote, s3, encryption) in each VM at least once.
If an error occurred while acquiring a lock on a remote server the error would be reported correctly, but the queue max detection code was not reached. The tests failed to detect this because they fixed the connection before queue max, allowing the ccde to be reached.
Move the queue max code before the lock so it will run even when remote connections are not working. This means that no attempt will be made to transfer WAL once queue max has been exceeded, but it makes it much more likely that the code will be reach without error.
Update tests to continue errors up to the point where queue max is exceeded.
Reported by Lardière Sébastien.
