Bug Fixes:
* Preserve block incremental info in manifest during delta backup. (Reviewed by Stephen Frost. Reported by Francisco Miguel Biete Banon.)
* Fix block incremental file names in verify command. (Reviewed by Reid Thompson. Reported by Francisco Miguel Biete Banon.)
* Fix spurious automatic delta backup on backup from standby. (Reviewed by Stephen Frost. Reported by krmozejko, Don Seiler.)
* Skip recovery.signal for PostgreSQL >= 12 when recovery type=none. (Reviewed by Stefan Fercot. Reported by T.Anastacio.)
* Fix unique label generation for diff/incr backup. (Fixed by Andrey Sokolov. Reviewed by David Steele.)
* Fix time-based archive expiration when no backups are expired. (Reviewed by Stefan Fercot.)
Improvements:
* Improve performance of SFTP storage driver. (Contributed by Stephen Frost, Reid Thompson. Reviewed by David Steele.)
* Add timezone offset to info command date/time output. (Reviewed by Stefan Fercot, Philip Hurst. Suggested by Philip Hurst.)
* Centralize error handling for unsupported features. (Reviewed by Stefan Fercot.)
Documentation Improvements:
* Clarify preference to install from packages in the user guide. (Reviewed by Stefan Fercot. Suggested by dr-kd.)
When performing backup from standby the file sizes on the standby may not be equal to file sizes on the primary. This is because replication continues during the backup and by the time the file is copied from the standby it may have changed. Since we cap the size of all files copied from the standby this practically applies to truncation and in particular truncation of free space maps (at least, every case we have seen so far is an fsm). Free space maps are especially vulnerable since they are only partially replicated, which amplifies the difference between the primary and standby.
On an incremental backup it may look like the size has changed on the primary (because of the final size recorded by the standby in the prior backup) but the timestamp may not have changed on the primary and this will trigger a checksum delta for safety. While this has no impact on backup integrity, checksum delta incrementals can run much longer than regular incrementals and backup schedules may be impacted.
The solution is to preserve the original size in the manifest and use it to do the time/size check. In the case of backup from standby the original size will always be the size on the primary, which makes comparisons against subsequent file sizes on the primary consistent. Original size is only stored in the manifest when it differs from final size, so there should not be any noticeable manifest bloat.
It was possible for block incremental info to be lost if a file had been modified in such a way that block incremental would be disabled if the file were new, e.g. if the file shrank below the block incremental limit or the file timestamp regressed far enough into the past. In those cases the block incremental info would not be copied in manifestBuildIncr().
Instead always copy the block incremental info in case the file ends up being referenced to a prior backup.
The validation tests were not robust enough to catch this issue so they were improved in 1d42aed.
In the particular case that exposed this bug, a file had a timestamp that was almost four weeks in the past at full backup time. A few days later a fail over occurred and the next incremental ran on the new primary (old standby) in delta mode. The same file had a timestamp just a few hours older than in the full backup, but now four weeks older than the current backup. Block incremental was disabled for the file on initial manifest build because of its age, which meant the block incremental info was not copied into the new manifest. The delta then determined the file had not changed and referenced it to the full backup. On restore, the file appeared to be a normal file stored in a bundle but could not be decompressed because it was in fact a block incremental.
The verify command was not appending the .pgbi extension instead of the compression extension when verifying block incremental files stored outside a bundle.
Originally the idea was that verify would not need any changes (since it just examines repo-size and checksum) but at some point the new extension was added and broke that assumption.
Use backupFileRepoPathP() to generate the correct filename (Just like backup, restore, etc).
Referenced files were not being checked for validity unless they were hard linked to the current backup (which a lot of the tests did). Newer tests with bundling do not have hard links and so missed these checks.
Improve the validation code to check referenced files in the manifest even when they are not hard linked into the current backup.
Add a delta test for bundling/block incremental that includes a file old enough to get a block size of zero. These are good tests by themselves but they also reduce the churn in an upcoming bug fix.
It is possible for the size of a file to change during the backup. In most cases we won't notice since files sizes are usually capped but it is possible for some files to grow or shrink between when they are recorded in the manifest and when they are actually copied. The new size is recorded in the manifest but the old size may be useful for debugging.
The new code has coverage but no test changes because it is covered by the parallel backup testing, which does not have deterministic log output. It doesn't seem worth creating a new test to check the log format as it is not very critical (though the output was manually verified).
Errors should be rare enough that it makes sense to log them at debug level. Right now if there is an error if won't be logged at debug level, which makes it harder to tell why the main process may have terminated the local/remote process.
Coverity complained about time_t being cast directly to unsigned int, so instead cast the result of the operation.
We are confident in both cases that the time_t values will not be out of unsigned int range but Coverity has no way to know that.
One of these is new (introduced by 9efd5cd0) but the other one (from a9867cb0) remained unnoticed for a while, though it has not caused any production impact.
The initial implementation used simple waits when having to loop due to getting a LIBSSH2_ERROR_EAGAIN, but we don't want to just wait some amount of time, we want to wait until we're able to read or write on the fd that we would have blocked on.
This change removes all of the wait code from the SFTP driver and changes the loops to call the newly introduced storageSftpWaitFd(), which in turn checks with libssh2 to determine the appropriate direction to wait on (read, write, or both) and then calls fdReady() to perform the wait using the provided timeout.
This also removes the need to pass ioSession or timeout down into the SFTP read/write code.
In the case that no backups were expired but time-based retention was met no archive expiration would occur and the following would be logged:
INFO: time-based archive retention not met - archive logs will not be expired
In most cases this was harmless, but when retention was first met or if retention was increased, it would require one additional backup to expire earlier WAL. After that expiration worked as normal.
Even once expiration was working normally the message would continue to be output, which was pretty misleading since retention had been met, even though there was nothing to do.
Bring this code in line with count-based retention, i.e. always log what should be expired at detail level (even if nothing will be expired) and then log info about what was expired (even if nothing is expired). For example:
DETAIL: repo1: 11-1 archive retention on backup 20181119-152138F, start = 000000010000000000000002
INFO: repo1: 11-1 no archive to remove
Seems easiest just to make the additional config required since it tests that custom ports are being used correctly. The test for synthetic was a noop since SFTP is not used in synthetic tests.
If there were at least two full backups and the last one was expired, it was impossible to make either a differential or incremental backup without first making a new full backup. The backupLabelCreate() function identified this situation as clock skew because the new backup label was compared with label of the expired full backup.
If the new backup is differential or incremental, then its label is now compared with the labels of differential or incremental backups related to the same full backup.
Also convert a hard-coded date length to a macro.
9ca492c missed adding auditing to this macro and as a result a few memory leaks have slipped through. Add auditing to the macro to close this hole.
Of the leaks found the only possibly serious one is in blockIncrProcess(), which would leak a PackRead of about eight bytes with every superblock. Since superblocks max out at a few thousand per file this was probably not too bad.
Also change the ordering of auditing in FUNCTION_TEST_RETURN_VOID(). Even though the order does not matter, having it different from the other macros is confusing and looks like an error.
This behavior is different than regular options where a repeated value will result in an error. It appears to be a legacy of the original Perl implementation, which used a hash as the underlying data type in the built-in command-line parser, and the C command-line parser was written to match.
This was missed in the C unit test migration and since then a new test was added that was not setting its timezone correctly.
This feature exists to make sure the tests will run on systems with different timezones and has no impact on the core code.
Deleting a stanza after all the storage driver stanzas were created was causing problems because the SFTP driver is slow and the GCS driver has no server (so it threw errors). This delayed the shutdown of PostgreSQL, which for some reason caused systemctl to hang when the documentation was being built on a RHEL host.
Move the section up and add a comment about why the location is required. Also add a comment to the GCS section about its location.
This does not address the issue of systemctl hanging on RHEL container hosts but it will hopefully make it less common.
Bring PostgreSQL >= 12 behavior in line with other versions when recovery type=none.
We are fairly sure this did not work correctly when PostgreSQL 12 was released, but apparently the issue has been fixed since then. Either way, after testing we have determined that the behavior is now as expected.
Some features are conditionally compiled into pgBackRest (e.g. lz4). Previously checking to see if the feature existed was the responsibility of the feature's module.
Centralize this logic in the config/parse module to make the errors more detailed and consistent.
This also fixes the assert that is thrown when SFTP storage is specified but SFTP support is not compiled into pgBackRest.
Combine StringId and int checking into a single loop. This seems more compact and makes it easier to add code that affects both types (and possibly more types in the future).
This was not tested in 87087fac and the generated config was only valid for pushing from the primary. Also do some general cleanup.
Update the SFTP server user to be "pgbackrest" instead of "postgres".
Even though sftp-all=y now creates a valid configuration, the user guide build still fails because SFTP is too slow and operations time out (particularly starting PostgreSQL). This will need to be addressed in a future commit.
This parameter is now optional and defaults to none so there is no reason to explicitly show it in user-facing documentation.
Also make the vm parameter in ci.pl optional to be consistent with how test.pl behaves.
The --no-log-timestamp option was missed when unit test building was migrated to C, which caused test timings to show up in the contributing guide. This caused no harm but did create churn in this file during releases.
Also improve the formatting when test timing is disabled.
Features:
* Block incremental backup. (Reviewed by John Morris, Stephen Frost, Stefan Fercot.)
* SFTP support for repository storage. (Contributed by Reid Thompson. Reviewed by Stephen Frost, David Steele.)
* PostgreSQL 16 support. (Reviewed by Stefan Fercot.)
Improvements:
* Allow page header checks to be skipped. (Reviewed by David Christensen. Suggested by David Christensen.)
* Avoid chown() on recovery files during restore. (Reviewed by Stefan Fercot, Marcelo Henrique Neppel. Suggested by Marcelo Henrique Neppel.)
* Add error retry detail for HTTP retries.
Documentation Improvements:
* Add warning about using recovery type=none. (Reviewed by Stefan Fercot.)
* Add note about running stanza-create on already-created repositories.
The prior timeouts were a bit aggressive and were causing timeouts in the Azure tests. There have also been occasional timeouts in other storage drivers.
The performance of CI environments is pretty variable so increased timeouts should make the tests more stable.
