The storage driver requires two list functions to be implemented, list and infoList. But the former is a subset of the latter so implementing both in every driver is wasteful. The reason both exist is that in Posix it is cheaper to get a list of names than it is to stat files to get size, time, etc. In S3 these operations are equivalent.
Introduce storageInfoLevelType to determine the amount of information required by the caller. That way Posix can work efficiently and all drivers can return only the data required which saves some bandwidth. The storageList() and storageInfoList() functions remain in the storage interface since they are useful -- the only change is simplifying the drivers with no external impact.
Note that since list() accepted an expression infoList() must now do so. Checking the expression is optional for the driver but can be used to limit results or save IO costs.
Similarly, exists() and pathExists() are just specialized forms of info() so adapt them to call info() instead.
This is really a socket option so the new name is clearer.
Since common/io/socket/tcp will contains a mix of options it makes sense to rename it to socket and cascade name changes as needed.
Prior to 2.25 the individual TCP keep-alive options were not being configured due to a missing header. In 2.25 they were being configured incorrectly due to a disconnect between the timeout specified in ms and what was expected by the TCP options, i.e. seconds.
Instead make the TCP keep-alive options directly configurable, with correct units and better testing. Keep-alive is enabled by default (though it can be defaulted to the system setting instead) and the rest of the options are not set by default. This is in line with what PostgreSQL does, though PostgreSQL does not allow keep-alive to be defaulted.
Also move configuration of TCP options before connect() as PostgreSQL does.
This functionality was embedded into TlsClient but that was starting to get unwieldy.
Add SocketClient to contain all socket-related client functionality.
The primary purpose of this test (currently) is to measure the performance of storageRemoteInfoList(), which is critical for building a manifest when the PostgreSQL host is remote.
The starting baseline of 1 million files is perhaps a bit aggressive but it seems very likely to blow up if there are performance regressions.
Add functions to select a current backup by label and to retrieve a backup dependency list for any given backup.
Update the expire code to utilize the new functions and to expire backup sets from newest dependency to oldest.
The manifest is excellent for validation but including the entire manifest is too noisy and some values are architecture/algorithm dependent.
Output a redacted version that contains the most important information which can be improved on over time.
These days it is better to include the module in define.yaml when we need to poke at the internal implementation.
This doesn't quite work for the log test harness, so for now some variables will need to remain extern'd in debug builds.
Enhance dry-run support added in 2fa69af8 by forbidding writes in the storage layer and adding prefixes to log messages.
The former will protect against mistakes in dry-run implementations and the latter will make it clear when a command was executed in dry-run mode.
Update expire unit tests with the new log prefix.
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.
These commands are generally useful but more importantly they allow removing LibC by providing the Perl integration tests an alternate way to work with repository storage.
All the commands are currently internal only and should not be used on production repositories.
This command only makes sense for the repository storage since other storage (e.g. pg and spool) must be located on a local Posix filesystem and can be listed using standard unix commands. Since the repo storage can be located lots of places having a common way to list it makes sense.
Prefix with repo- to make the scope of this command clear.
Update documentation to reflect this change.
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.
The postgres/pageChecksum module was designed as an interface to the C structs for the Perl code. The new C code can do this directly so no need for an interface.
Move the remaining test for pgPageChecksum() into the postgres/interface test module.
This function made validation faster in Perl because fewer calls (and buffer transformations) were required when all checksums were valid.
In C calling pageChecksumTest() directly is just as efficient so there is no longer a need for pageChecksumBufferTest().
This was a minor optimization used in protocol layer compression. Even though it was slightly faster, it omitted the crc-32 that is generated during normal compression which could lead to corrupt data after a bad network transmission. This would be caught on restore by our checksum but it seems better to catch an issue like this early.
The raw option also made the function signature different than future compression formats which may not support raw, or require different code to support raw.
In general, it doesn't seem worth the extra testing to support a format that has minimal benefit and is seldom used, since protocol compression is only enabled when the transmitted data is uncompressed.
"gz" was used as the extension but "gzip" was generally used for function and type naming.
With a new compression format on the way, it makes sense to standardize on a single abbreviation to represent a compression format in the code. Since the extension is standard and we must use it, also use the extension for all naming.
Auto-selection is performed only when --set is not specified. If a backup set for the given target time cannot not be found, the latest (default) backup set will be used.
Currently a limited number of date formats are recognized and timezone names are not allowed, only timezone offsets.
These are similar to what mktime() and strptime() do but they ignore the local system timezone which saves having to munge the TZ env variable to do time conversions.
Remove embedded Perl from the distributed binary. This includes code, configure, Makefile, and packages. The distributed binary is now pure C.
Remove storagePathEnforceSet() from the C Storage object which allowed Perl to write outside of the storage base directory. Update mock/all and real/all integration tests to use storageLocal() where they were violating this rule.
Remove "c" option that allowed the remote to tell if it was being called from C or Perl.
Code to convert options to JSON for passing to Perl (perl/config.c) has been moved to LibC since it is still required for Perl integration tests.
Update build and installation instructions in the user guide.
Remove all Perl unit tests.
Remove obsolete Perl code. In particular this included all the Perl protocol code which required modifications to the Perl storage, manifest, and db objects that are still required for integration testing but only run locally. Any remaining Perl code is required for testing, documentation, or code generation.
Rename perlReq to binReq in define.yaml to indicate that the binary is required for a test. This had been the actual meaning for quite some time but the key was never renamed.
For the most part this is a direct migration of the Perl code into C except as noted below.
A backup can now be initiated from a linked directory. The link will not be stored in the manifest or recreated on restore. If a link or directory does not already exist in the restore location then a directory will be created.
The logic for creating backup labels has been improved and it should no longer be possible to get a backup label earlier than the latest backup even with timezone changes or clock skew. This has never been an issue in the field that we know of, but we found it in testing.
For online backups all times are fetched from the PostgreSQL primary host (before only copy start was). This doesn't affect backup integrity but it does prevent clock skew between hosts affecting backup duration reporting.
Archive copy now works as expected when the archive and backup have different compression settings, i.e. when one is compressed and the other is not. This was a long-standing bug in the Perl code.
Resume will now work even if hardlink settings have been changed.
Reviewed by Cynthia Shang.
Previously we were using int64_t to debug time_t but this may not be right depending on how the compiler represents time_t, e.g. it could be a float.
Since a mismatch would have caused a compiler error we are not worried that this has actually happened, and anyway the worst case is that the debug log would be wonky.
The primary benefit, aside from correctness, is that it makes choosing a parameter debug type for time_t obvious.
Note that building the manifest on each host has been temporarily removed.
This feature will likely be brought back as a non-default option (after the manifest code has been fully migrated to C) since it can be fairly expensive.
Three major changes were required to get this working:
1) Provide the path to pgbackrest in the build directory when running outside a container. Tests in a container will continue to install and run against /usr/bin/pgbackrest.
1) Set a per-test lock path so tests don't conflict on the default /tmp/pgbackrest path. Also set a per-test log-path while we are at it.
2) Use localhost instead of a custom host for TLS test connections. Tests in containers will continue to update /etc/hosts and use the custom host.
Add infrastructure and update harnessCfgLoad*() to get the correct exe and paths loaded for testing.
Since new tests are required to verify that running outside a container works, also rework the tests in Travis CI to provide coverage within a reasonable amount of time. Mainly, break up to doc tests by VM and run an abbreviated unit test suite on co6 and co7.
Recovery settings are now written into postgresql.auto.conf instead of recovery.conf. Existing recovery_target* settings will be commented out to help avoid conflicts.
A comment is added before recovery settings to identify them as written by pgBackRest since it is unclear how, in general, old settings will be removed.
recovery.signal and standby.signal are automatically created based on the recovery settings.
bsearch() is far more efficient than an iterative approach except in the most trivial cases.
For now insert will reset the sort order to none and the list will need to be resorted before bsearch() can be used. This is necessary because item pointers are not stable after a sort, i.e. they can move around. Until lists are stable it's not a good idea to surprise the caller by mixing up their pointers on insert.
For the most part this is a direct migration of the Perl code into C.
There is one important behavioral change with regard to how file permissions are handled. The Perl code tried to set ownership as it was in the manifest even when running as an unprivileged user. This usually just led to errors and frustration.
The C code works like this:
If a restore is run as a non-root user (the typical scenario) then all files restored will belong to the user/group executing pgBackRest. If existing files are not owned by the executing user/group then an error will result if the ownership cannot be updated to the executing user/group. In that case the file ownership will need to be updated by a privileged user before the restore can be retried.
If a restore is run as the root user then pgBackRest will attempt to recreate the ownership recorded in the manifest when the backup was made. Only user/group names are stored in the manifest so the same names must exist on the restore host for this to work. If the user/group name cannot be found locally then the user/group of the PostgreSQL data directory will be used and finally root if the data directory user/group cannot be mapped to a name.
Reviewed by Cynthia Shang.
The backup manifest stores a complete list of all files, links, and paths in a backup along with metadata such as checksums, sizes,
timestamps, etc. A list of databases is also included for selective restore.
The purpose of the manifest is to allow the restore command to confidently reconstruct the PostgreSQL data directory and ensure that
nothing is missing or corrupt. It is also useful for reporting, e.g. size of backup, backup time, etc.
For now, migrate enough functionality to implement the restore command.
Reviewed by Cynthia Shang.
The control and catalog versions were stored a variety of places in the optimistic hope that they would be useful. In fact they never were.
We can't remove them from the backup.info and backup.manifest files due to backwards compatibility concerns, but we can at least avoid loading and storing them in C structures.
Add functions to the PostgreSQL interface which will return the control and catalog versions for any supported version of PostgreSQL to allow backwards compatibility for backup.info and backup.manifest. These functions will be useful in other ways, e.g. generating the tablespace identifier in PostgreSQL >= 9.0.
Info files required three copies in memory to be loaded (the original string, an ini representation, and the final info object). Not only was this memory inefficient but the Ini object does sequential scans when searching for keys making large files very slow to load.
This has not been an issue since archive.info and backup.info are very small, but it becomes a big deal when loading manifests with hundreds of thousands of files.
Instead of holding copies of the data in memory, use a callback to deliver the ini data directly to the object when loading. Use a similar method for save to avoid having an intermediate copy. Save is a bit complex because sections/keys must be written in alpha order or older versions of pgBackRest will not calculate the correct checksum.
Also move the load retry logic to helper functions rather than embedding it in the Info object. This allows for more flexibility in loading and ensures that stack traces will be available when developing unit tests.
Reviewed by Cynthia Shang.
Checking the PostgreSQL-reported path and version against the pgBackRest configuration helps ensure that pgBackRest is operating against the correct cluster.
In Perl this functionality was in the Db object, but check seems like a better place for it in C.
Contributed by Cynthia Shang.
Previously, info files (e.g. archive.info, backup.info) were created in Perl and only loaded in C.
The upcoming stanza commands in C need to create these files so refactor the Info* objects to allow new, empty objects to be created. Also, add functions needed to initialize each Info* object to a valid state.
Contributed by Cynthia Shang.
Calculate the most common value in a list of variants. If there is a tie then the first value passed to mcvUpdate() wins.
mcvResult() can be called multiple times because it does not end processing, but there is a cost to calculating the result each time
since it is not stored.
