Bundle (combine) smaller files during backup to reduce the number of files written to the repository (enable with --bundle). Reducing the number of files is a benefit on all file systems, but especially so on object stores such as S3 that have a high file creation cost. Another benefit is that zero-length files are only stored as metadata in the manifest.
Files are batched up to bundle-size and then compressed/encrypted individually and stored sequentially in the bundle. The bundle id and offset of each file is stored in the manifest so files can be retrieved randomly without needing to read the entire bundle. Files are ordered by timestamp descending when being assigned to bundles to reduce the amount of random access that needs to be done. The idea is that bundles with older files can be read in their entirety on restore and only bundles with newer files will get fragmented.
Bundles are a custom format with metadata stored in the manifest. Tar was considered but it is too limited a format, the major issue being that the size of the file must be known in advance and that is very contrary to how pgBackRest works, especially once we introduce page-level incremental backups.
Bundles are stored numbered in the bundle directory. Some files may still end up in pg_data if they are added after the backup is complete. backup_label is an example.
Currently, only the backup command works in batches. The restore and verify commands use the offsets to pull individual files out of the bundle. It seems better to finalize how this is going to work before optimizing the other commands. Even as is, this is a major step forward, and all commands function with bundling.
One caveat: resume is currently not supported when bundle is enabled.
Manifest defaults for user, group, and mode were previously generated by scanning the data to find the most common values. This was very accurate but slow and complicated. It could also lead to surprising changes in the manifest when a default value suddenly changed.
Instead, use the $PGDATA path to generate defaults. In the vast majority of cases the same user/group should own all the path/files and the default file mode is easily derived from the path mode. There may be some edge cases where this generates larger manifests, but in general it reduces time and complexity when saving the manifest.
Remove the MCV code since it is longer longer used.
Change the mode back to 0700 earlier to reduce churn in the expect logs.
This will be especially important in a future commit that gets the defaults exclusively from the base path.
This flag was only being used by the backup command after manifestNewBuild() and had no other uses. There was a time when it was important for integration testing but the unit tests now fulfill this role.
Since backup is the only code concerned with the primary flag, move the code into the backup module.
We don't have any cross-version testing but this change was tested manually with the most recent version of pgBackRest to make sure it was tolerant of the missing primary info. When an older version of pgBackRest loads a newer manifest the primary flag will always be set to false, which is fine since it is not used.
Properly log the size of files copied during the backup, matching the backup size returned from the info command.
In the reference issue, the incremental backup after switchover logs the size of all files evaluated rather than only the size of the files copied in the backup.
Azurite released another breaking change (see fbd018cd, 096829b3, c38d6926, and Azurite issue 1039) so make adjustments as needed to documentation and tests.
Also remove some dead code that hid the repo-storage-host option and was made obsolete by all these changes.
The TLS server is an alternative to using SSH for protocol connections to remote hosts.
This command is currently experimental and intended only for trial and testing. As such, the new commands and options will not show up in the command-line help unless directly requested.
Currently errors found during the backup are only available in text output when specifying --set.
Add a flag to backup.info that is available in both the text and json output when --set is not specified. This at least provides the basic info that an error was found in the cluster during the backup, though details are still only available as described above.
The prior limitations were based on using getopt_long() to parse command-line options, which required a static list of allowed options. Setting index max too high bloated the binary unacceptably. 45a4e80 replaced the functionality of getopt_long() but the static list remained.
Improve cfgParseOption() to use available option data and remove the need for a static list. This also allows the option deprecations to be represented more compactly.
Index max is still capped at 256 because a large enough index could cause parseOptionIdxValue() to run out of memory since it allocates a static list based on the highest index found. If that function were improved with a map of found index values then index max could be set to UINT64_MAX.
Note that deprecations no longer set an index max or define whether reset is valid. These were space-saving measures which are no longer required. This means that indexed deprecated options will also be valid up to 256 and always allow reset, but it doesn't seem worth additional code to limit this behavior.
cfgParseOptionId() is no longer needed because calling cfgParseOption() with .ignoreMissingIndex = true duplicates the functionality of cfgParseOptionId(). This leads to some simplification in the help code.
The backup size was a bit off because it did not include any files (e.g. backup_label, WAL files) that were added to the manifest after the main copy. To fix this move the log message to the very end of the backup.
Add size/file total log message to restore since it did not exist before.
The log level for copied files in the backup/restore commands has been changed to detail. This makes the info log level less noisy but if these messages are required then set the log level for the backup/restore commands to detail.
Azurite, which is used for testing, did not enforce this before so the capital letters were not a problem. Now Azurite enforces the same rules as Azure so use lower-case identifiers instead.
These names were only used in integration tests so there was no production impact.
Remove stanza archive spool path so existing files do not interfere with the new cluster. For instance, old archive-push acknowledgements could cause a new cluster to skip archiving. This should not happen if a new timeline is selected but better to be safe. Missing stanza spool paths are ignored.
Also add new path expression STORAGE_SPOOL_ARCHIVE to easily access this path.
3b8f0ef missed some cases that could cause archive-push to fail:
* Checking archive info.
* Checking to see if a WAL segment already exists.
These cases are now handled so archive-push can succeed on any valid repos.
Some standard system databases (e.g. postgres) may be recreated by the user and have an OID that makes them look like user databases.
Identify the standard three system databases (template0, template1, postgres) and restore them non-zeroed no matter what OID they have.
The stanza-create, stanza-upgrade and stanza-delete were required to be run on the repository host. When there was only one repository allowed this was not a problem.
However, with the introduction of multiple repository support, this becomes more of a burden to the user, therefore the stanza-create, stanza-upgrade and stanza-delete commands have been improved to allow for them to be run remotely.
Up to four repositories may be configured. A potential benefit is the ability to have a local repository for fast restores and a remote repository for redundancy.
Some commands, e.g. stanza-create/stanza-update, will automatically work with all configured repositories while others, e.g. stanza-delete, will require a repository to be specified using the repo option. See the command reference for details on which commands require the repository to be specified.
Note that the repo option is not required when only repo1 is configured in order to maintain backward compatibility. However, the repo option is required when a single repo is configured as, e.g. repo2. This is to prevent command breakage if a new repository is added later.
The archive-push command will always push WAL to the archive in all configured repositories but backups will need to be scheduled individually for each repository. In many cases this is desirable since backup types and retention will vary by repository. Likewise, restores must specify a repository. It is generally better to specify a repository for restores that has low latency/cost even if that means more recovery time. Only restore testing can determine which repository will be most efficient.
For single repository configurations there should be no change in behavior.
The following options are renamed as specified:
repo1-azure-ca-file -> repo1-storage-ca-file
repo1-azure-ca-path -> repo1-storage-ca-path
repo1-azure-host -> repo1-storage-host
repo1-azure-port -> repo1-storage-port
repo1-azure-verify-tls -> repo1-storage-verify-tls
repo1-s3-ca-file -> repo1-storage-ca-file
repo1-s3-ca-path -> repo1-storage-ca-path
repo1-s3-host -> repo1-storage-host
repo1-s3-port -> repo1-storage-port
repo1-s3-verify-tls -> repo1-storage-verify-tls
The old option names (e.g. repo1-s3-port) will continue to work for repo1, but repo2, etc. will require the new names.
The restore command automatically defaults to selecting the latest backup from a single repository. With multiple repositories configured, the restore command will now default to selecting the latest backup from the first repository where backups exist. The order in which the repositories are checked is dictated by the pgbackrest.conf order.
To select from a specific repository, the --repo option can be passed (e.g. --repo=1). The --set option can be passed if a backup other than the latest is desired.
Repositories will be searched in order for the requested archive file.
Errors will be reported as warnings as long as a valid copy of the archive file is found.
Errors are logged to the log file rather than thrown. If, after processing all repos, one or more errors occurred, then a single error error will be thrown to indicate there were errors and the log file should be inspected.
Also update log messages to be more consistent with new patterns.
In preparation for multi-repo support, a repo tag is added in this commit to the expire command log and error messages. This change also affects the expect logs and the user-guide. The format of the tag is "repoX:" where X is the repo key used in the configuration.
Until multi-repo support has been completed, this tag will always be "repo1:".
Multi-repository implementations for the archive-push, check, info, stanza-create, stanza-upgrade, and stanza-delete commands.
Multi-repo configuration is disabled so there should be no behavioral changes between these commands and their current single-repo implementations.
Multi-repo documentation and integration tests are still in the multi-repo development branch. All unit tests work as multi-repo since they are able to bypass the configuration restrictions.
Check that archive files exist in the main process instead of the local process. This means that the archive.info file only needs to be loaded once per execution rather than once per file to get.
Stop looking when a file is missing or in error. PostgreSQL will never request anything past the missing file so there is no point in getting them. This also reduces "unable to find" logging in the async process.
Cache results of storageList() when looking for multiple files to reduce storage I/O.
Look for all requested archive files in the archive-id where the first file is found. They may not all be there, but this reduces the number of list calls. If subsequent files are in another archive id they will be found on the next archive-get call.
Append "asynchronously" to messages when the async process fetched the file (not in the actual async process log, though).
Add "repo1" to make it clear what archive we are talking about. This is not very useful by itself but soon we'll be able to add the archive id, which is very useful.
Add constants for messages that are used multiple times to ensure they stay consistent.
These options specify the number of local worker job retries and the retry interval after one immediate retry.
There is some value in allowing retries to be specified by the user but for the most part these options are for suppressing retries during testing, which can save a lot of time. The bug introduced in d1d25c7 and fixed in 8b86d5e also suggests it is better not to use retries in tests.
Remove the default delayed retries for archive-get/archive-push, leaving only the immediate retry. These commands are retried by PostgreSQL so it doesn't make sense to do too many retries internally.
These options are currently internal.
No timeout is expected here but the small timeout prevents errors from being thrown.
This is not a bug since the error would be thrown on the next archive-get call but it does make the tests harder to debug when there is an error.
It is not clear why there was a timeout here at all. It is likely cruft from a prior test or a copy/paste error.
Improve locking on remote processes by introducing an exec-id that is unique to the main process and passed to all remote processes. This allows the remote processes to determine if a lock is held by a remote from the same main process. If so, the lock is allowed.
The exec-id is also useful for associating remote logs with main logs for debugging purposes.
Currently indexes above 1 do not have dependencies checked, so this doesn't error.
In a future commit we will enable those checks and this will error if it is not fixed.
Currently each module that needs to collect statistics implements custom code to do so. This is cumbersome.
Create a general purpose module for collecting and reporting statistics. Statistics are output in the log at detail level, but there are other uses they could be put to eventually.
No new functionality is added. This is just a drop-in replacement for the current statistics, with the advantage of being more flexible.
The new stats are slower because they involve a list lookup, but performance testing shows stats can be updated at about 40,000/ms which seems fast enough for our purposes.
Remove all check and stanza-* tests except for the ones that are intended to succeed. The successful tests show that the queries run with expected results against each version of PG which should also validate queries for the failure tests in the unit tests.
Also remove the tests for --no-online backups since they don't require a database and are well tested in the unit tests.
Azure and Azure-compatible object stores can now be used for repository storage.
Currently only shared key authentication is supported but SAS will be added soon.
When uploading large files the upload is split into multiple parts which are assembled at the end to create the final file. Previously we waited until each part was acknowledged before starting on the processing (i.e. compression, etc.) of the next part.
Now, the request for each part is sent while processing continues and the response is read just before sending the request for the next part. This asynchronous method allows us to continue processing while the S3 server formulates a response.
Testing from outside AWS in a high-bandwidth, low-latency environment showed a 35% improvement in the upload time of 1GB files. The time spent waiting for multipart notifications was reduced by ~300% (this measurement included the final part which is not uploaded asynchronously).
There are still some possible improvements: 1) the creation of the multipart id could be made asynchronous when it looks like the upload will need to be multipart (this may incur cost if the upload turns out not to be multipart). 2) allow more than one async request (this will use more memory).
A fair amount of refactoring was required to make the HTTP responses asynchronous. This may seem like overkill but having well-defined request, response, and session objects will also be advantageous for the upcoming HTTP server functionality.
Another advantage is that the lifecycle of an HttpSession is better defined. We only want to reuse sessions that complete the request/response cycle successfully, otherwise we consider the session to be in a bad state and would prefer to start clean with a new one. Previously, this required complex notifications to mark a session as "successfully done". Now, ownership of the session is passed to the request and then the response and only returned to the client after a successful response. If an error occurs anywhere along the way the session will be automatically closed by the object destructor when the request/response object is freed (depending on which one currently owns the session).
Test matrices were previously simplified for the mock/* tests (e.g. d4410611, d489eb87) but not for real/all since the rules for which tests would run with which options was extremely complex. This only got more complex when new compression formats were added.
Because the loop-generated matrix was so large, mosts tests were skipped for most option combinations following arcane logic which was nearly impossible to decipher even when reading the code, and completely impossible from the test.pl interface. As a consequence, important tests got excluded. For example, backup from standby was excluded for most versions of PostgreSQL because it was only run once per distro, against the latest version to be included in that distro.
Simplify the tests by having a single run per PostgreSQL version and vary test parameters according to the capabilities of each version and the underlying distro. So, ZST testing is based on whether the distro supports ZST. Every test is run for each set of parameters based on the capabilities of the PostgreSQL version, e.g. backup from standby is not attempted on versions that don't support it.
Note that since more tests are running the overall time to run the mock/all tests has increased by about 20-25%. Some time may be saved my removing tests that are adequately covered by unit tests but that should the subject of another commit. Another option would be to limit some non version-specific tests to a single, well defined version of PostgreSQL, .e.g the version that is run by expect tests, currently 9.6.
The motivation for this refactor is that new storage drivers are coming and the loop-generated test matrix simply was not up to the task of adding them.
The following is an example of the new test log (note longer runtime of each test):
module=real, test=all, run=1, pg-version=10 (106.91s)
module=real, test=all, run=1, pg-version=9.5 (151.09s)
module=real, test=all, run=1, pg-version=9.2 (123.11s)
module=real, test=all, run=1, pg-version=9.1 (129s)
vs. the old test log (sub-second tests were skipped entirely):
module=real, test=all, run=2, pg-version=10 (0.31s)
module=real, test=all, run=3, pg-version=10 (0.26s)
module=real, test=all, run=4, pg-version=10 (60.39s)
module=real, test=all, run=1, pg-version=10 (69.12s)
module=real, test=all, run=6, pg-version=10 (34s)
module=real, test=all, run=5, pg-version=10 (42.75s)
module=real, test=all, run=2, pg-version=9.5 (0.21s)
module=real, test=all, run=3, pg-version=9.5 (0.21s)
module=real, test=all, run=4, pg-version=9.5 (0.21s)
module=real, test=all, run=5, pg-version=9.5 (0.26s)
module=real, test=all, run=6, pg-version=9.5 (0.21s)
module=real, test=all, run=1, pg-version=9.2 (72.78s)
module=real, test=all, run=2, pg-version=9.2 (0.26s)
module=real, test=all, run=3, pg-version=9.2 (0.31s)
module=real, test=all, run=4, pg-version=9.2 (0.21s)
module=real, test=all, run=5, pg-version=9.2 (0.21s)
module=real, test=all, run=6, pg-version=9.2 (0.21s)
module=real, test=all, run=1, pg-version=9.5 (88.41s)
module=real, test=all, run=2, pg-version=9.1 (0.21s)
module=real, test=all, run=3, pg-version=9.1 (0.26s)
module=real, test=all, run=4, pg-version=9.1 (0.21s)
module=real, test=all, run=5, pg-version=9.1 (0.31s)
module=real, test=all, run=6, pg-version=9.1 (0.26s)
module=real, test=all, run=1, pg-version=9.1 (72.4s)
This aligns better with general PostgreSQL usage and our own documentation (updated in 4bcef702).
Usage in the backup.manifest tests has not been updated since it might break the file format.
Rather than bS3 use strStorage which can indicate more than two storage types.
For the moment there are still only two storage types but this change is required before more can be added.
The --repo-retention-full-type option allows retention of full backups based on a time period, specified in days.
The new option will default to 'count' and therefore will not affect current installations. Setting repo-retention-full-type to 'time' will allow the user to use a time period, in days, to indicate full backup retention. Using this method, a full backup can be expired only if the time the backup completed is older than the number of days set with repo-retention-full (calculated from the moment the 'expire' command is run) and at least one full backup meets the retention period. If archive retention has not been configured, then the default settings will expire archives that are prior to the oldest retained full backup. For example, if there are three full backups ending in times that are 25 days old (F1), 20 days old (F2) and 10 days old (F3), then if the full retention period is 15 days, then only F1 will be expired; F2 will be retained because F1 is not at least 15 days old.
Zstandard is a fast lossless compression algorithm targeting real-time compression scenarios at zlib-level and better compression ratios. It's backed by a very fast entropy stage, provided by Huff0 and FSE library.
Zstandard version >= 1.0 is required, which is generally only available on newer distributions.
