pg_basebackup knows how to do quite a few things with a backup that it
gets from the server, like just write out the files, or compress them
first, or even parse the tar format and inject a modified
postgresql.auto.conf file into the archive generated by the server.
Unforatunely, this makes pg_basebackup.c a very large source file, and
also somewhat difficult to enhance, because for example the knowledge
that the server is sending us a 'tar' file rather than some other sort
of archive is spread all over the place rather than centralized.
In an effort to improve this situation, this commit invents a new
'bbstreamer' abstraction. Each archive received from the server is
fed to a bbstreamer which may choose to dispose of it or pass it
along to some other bbstreamer. Chunks may also be "labelled"
according to whether they are part of the payload data of a file
in the archive or part of the archive metadata.
So, for example, if we want to take a tar file, modify the
postgresql.auto.conf file it contains, and the gzip the result
and write it out, we can use a bbstreamer_tar_parser to parse the
tar file received from the server, a bbstreamer_recovery_injector
to modify the contents of postgresql.auto.conf, a
bbstreamer_tar_archiver to replace the tar headers for the file
modified in the previous step with newly-built ones that are
correct for the modified file, and a bbstreamer_gzip_writer to
gzip and write the resulting data. Only the objects with "tar"
in the name know anything about the tar archive format, and in
theory we could re-archive using some other format rather than
"tar" if somebody wanted to write the code.
These chances do add a substantial amount of code, but I think the
result is a lot more maintainable and extensible. pg_basebackup.c
itself shrinks by roughly a third, with a lot of the complexity
previously contained there moving into the newly-added files.
Patch by me. The larger patch series of which this is a part has been
reviewed and tested at various times by Andres Freund, Sumanta
Mukherjee, Dilip Kumar, Suraj Kharage, Dipesh Pandit, Tushar Ahuja,
Mark Dilger, Sergei Kornilov, and Jeevan Ladhe.
Discussion: https://postgr.es/m/CA+TgmoZGwR=ZVWFeecncubEyPdwghnvfkkdBe9BLccLSiqdf9Q@mail.gmail.com
Discussion: https://postgr.es/m/CA+TgmoZvqk7UuzxsX1xjJRmMGkqoUGYTZLDCH8SmU1xTPr1Xig@mail.gmail.com
pg_receivewal includes since cada1af the option --compress, to allow the
compression of WAL segments using gzip, with a value of 0 (the default)
meaning that no compression can be used.
This commit introduces a new option, called --compression-method, able
to use as values "none", the default, and "gzip", to make things more
extensible. The case of --compress=0 becomes fuzzy with this option
layer, so we have made the choice to make pg_receivewal return an error
when using "none" and a non-zero compression level, meaning that the
authorized values of --compress are now [1,9] instead of [0,9]. Not
specifying --compress with "gzip" as compression method makes
pg_receivewal use the default of zlib instead (Z_DEFAULT_COMPRESSION).
The code in charge of finding the streaming start LSN when scanning the
existing archives is refactored and made more extensible. While on it,
rename "compression" to "compression_level" in walmethods.c, to reduce
the confusion with the introduction of the compression method, even if
the tar method used by pg_basebackup does not rely on the compression
method (yet, at least), but just on the compression level (this area
could be improved more, actually).
This is in preparation for an upcoming patch that adds LZ4 support to
pg_receivewal.
Author: Georgios Kokolatos
Reviewed-by: Michael Paquier, Jian Guo, Magnus Hagander, Dilip Kumar,
Robert Haas
Discussion: https://postgr.es/m/ZCm1J5vfyQ2E6dYvXz8si39HQ2gwxSZ3IpYaVgYa3lUwY88SLapx9EEnOf5uEwrddhx2twG7zYKjVeuP5MwZXCNPybtsGouDsAD1o2L_I5E=@pm.me
Previously, BASE_BACKUP used an entirely hard-coded syntax, but that's
hard to extend. Instead, adopt the same kind of syntax we've used for
SQL commands such as VACUUM, ANALYZE, COPY, and EXPLAIN, where it's
not necessary for all of the option names to be parser keywords.
In the new syntax, most of the options now take an optional Boolean
argument. To match our practice in other in places, the options which
the old syntax called NOWAIT and NOVERIFY_CHECKSUMS options are in the
new syntax called WAIT and VERIFY_CHECKUMS, and the default value is
false. In the new syntax, the FAST option has been replaced by a
CHECKSUM option whose value may be 'fast' or 'spread'.
This commit does not remove support for the old syntax. It just adds
the new one as an additional option, and makes pg_basebackup prefer
the new syntax when the server is new enough to support it.
Patch by me, reviewed and tested by Fabien Coelho, Sergei Kornilov,
Fujii Masao, and Tushar Ahuja.
Discussion: http://postgr.es/m/CA+TgmobAczXDRO_Gr2euo_TxgzaH1JxbNxvFx=HYvBinefNH8Q@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoZGwR=ZVWFeecncubEyPdwghnvfkkdBe9BLccLSiqdf9Q@mail.gmail.com
Also remove obsolete comments about why the 64-bit integers need to be
printed in a separate buffer. The reason used to be portability, but
now the remaining reason is that we need the string lengths for the
progress displays. That is evident by looking at the code right
below, so a new comment doesn't seem necessary.
The following changes are done:
- In pg_archivecleanup, the cleanup of older WAL segments would never
fail immediately.
- In pgbench, the initialization of a thread barrier would not fail
hard.
- In pg_recvlogical, a stat() failure never got the call.
- In pg_basebackup, two chmod() reported a failure without exit()'ing
when unpacking some tar data freshly received. It may be possible to
continue writing some data even after this failure, but that could be
confusing to the user at the end.
These are arguably bugs, but they would happen for code paths where a
failure is unlikely going to happen, so no backpatch is done.
Reviewed-by: Robert Haas, Fabien Coelho
Discussion: https://postgr.es/m/YQDMdB+B68yePFeT@paquier.xyz
This fixes two compilation failures caused by 6f164e6. Interesting to
see that missing <limits.h> dies not fail in Linux or even Windows. On
MacOS, it fails, though.
Per various buildfarm members.
Most of the integer options for command-line binaries now make use of a
single routine able to do the job, fixing issues with the detection of
sloppy values caused for example by the use of atoi(), that fails on
strings beginning with numerical characters with junk trailing
characters.
This commit cuts down the number of strings requiring translation by 26
per my count, switching the code to have two error types for invalid and
out-of-range values instead.
Much more could be done here, with float or even int64 options, but
int32 was the most appealing case as it is possible to rely on strtol()
to do the job reliably. Note that there are some exceptions for now,
like pg_ctl or pg_upgrade that use their own logging logic. A couple of
negative TAP tests required some adjustments for the new errors
generated.
pg_dump and pg_restore tracked the maximum number of parallel jobs
within the option parsing. The code is refactored a bit to track that
in the code dedicated to parallelism instead.
Author: Kyotaro Horiguchi, Michael Paquier
Reviewed-by: David Rowley, Álvaro Herrera
Discussion: https://postgr.es/m/CALj2ACXqdG9WhqVoJ9zYf-iZt7sgK7Szv5USs=he6NnWQ2ofTA@mail.gmail.com
Extend the replication command CREATE_REPLICATION_SLOT to support the
TWO_PHASE option. This will allow decoding commands like PREPARE
TRANSACTION, COMMIT PREPARED and ROLLBACK PREPARED for slots created with
this option. The decoding of the transaction happens at prepare command.
This patch also adds support of two-phase in pg_recvlogical via a new
option --two-phase.
This option will also be used by future patches that allow streaming of
transactions at prepare time for built-in logical replication. With this,
the out-of-core logical replication solutions can enable replication of
two-phase transactions via replication protocol.
Author: Ajin Cherian
Reviewed-By: Jeff Davis, Vignesh C, Amit Kapila
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/64b9f783c6e125f18f88fbc0c0234e34e71d8639.camel@j-davis.com
A number of client programs have a "--progress" option that when printing
to a TTY, updates the current line by printing a '\r' and overwriting it.
After the last line, '\n' needs to be printed to move the cursor to the
next line. pg_basebackup and pgbench got this right, but pg_rewind and
pg_checksums were slightly wrong. pg_rewind printed the newline to stdout
instead of stderr, and pg_checksums printed the newline even when not
printing to a TTY. Fix them, and also add a 'finished' argument to
pg_basebackup's progress_report() function, to keep it consistent with
the other programs.
Backpatch to v12. pg_rewind's newline was broken with the logging changes
in commit cc8d415117 in v12, and pg_checksums was introduced in v12.
Discussion: https://www.postgresql.org/message-id/82b539e5-ae33-34b0-1aee-22b3379fd3eb@iki.fi
A few places calling fwrite and gzwrite were not setting errno to ENOSPC
when reporting errors, as is customary; this led to some failures being
reported as
"could not write file: Success"
which makes us look silly. Make a few of these places in pg_dump and
pg_basebackup use our customary pattern.
Backpatch-to: 9.5
Author: Justin Pryzby <pryzby@telsasoft.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20200611153753.GU14879@telsasoft.com
Introduce TAR_BLOCK_SIZE and replace many instances of 512 with
the new constant. Introduce function tarPaddingBytesRequired
and use it to replace numerous repetitions of (x + 511) & ~511.
Add preprocessor guards against multiple inclusion to pgtar.h.
Reformat the prototype for tarCreateHeader so it doesn't extend
beyond 80 characters.
Discussion: http://postgr.es/m/CA+TgmobWbfReO9-XFk8urR1K4wTNwqoHx_v56t7=T8KaiEoKNw@mail.gmail.com
Includes some manual cleanup of places that pgindent messed up,
most of which weren't per project style anyway.
Notably, it seems some people didn't absorb the style rules of
commit c9d297751, because there were a bunch of new occurrences
of function calls with a newline just after the left paren, all
with faulty expectations about how the rest of the call would get
indented.
When pg_basebackup -R is used, we inject standby.signal into the
tar file for the main tablespace. The proper thing to do is to pad
each file injected into the tar file out to a 512-byte boundary
by appending nulls, but here the file is of length 0 and we add
511 zero bytes. Since 0 is already a multiple of 512, we should
not add any zero bytes. Do that instead.
Patch by me, reviewed by Tom Lane.
Discussion: http://postgr.es/m/CA+TgmobWbfReO9-XFk8urR1K4wTNwqoHx_v56t7=T8KaiEoKNw@mail.gmail.com
Since 0d8c9c1, pg_basebackup would generate an error if connected to a
backend version older than 12 where backup manifests are not supported.
Avoiding this error is possible by using the --no-manifest option.
This error handling could be confusing for some users, where patching a
backup script that interacts with multiple backend versions would cause
the addition of --no-manifest to potentially not generate a backup
manifest even for Postgres 13 and newer versions. As we want to
encourage the use of backup manifests as much as possible, this commit
silently disables manifests where not supported, instead of generating
an error.
While on it, rework a bit the code to make it more consistent with the
surroundings when generating the BASE_BACKUP command.
Per discussion with Andres Freund, Stephen Frost, Robert Haas, Álvaro
Herrera, Kyotaro Horiguchi, Tom Lane, David Steele, and me.
Author: Michael Paquier
Discussion: https://postgr.es/m/20200410080910.GZ1606@paquier.xyz
This commit prevents pg_basebackup from receiving backup_manifest file
when --no-manifest is specified. Previously, when pg_basebackup was
writing a tarfile to stdout, it tried to receive backup_manifest file even
when --no-manifest was specified, and reported an error.
Also remove unused -m option from pg_basebackup.
Also fix typo in BASE_BACKUP command documentation.
Author: Fujii Masao
Reviewed-by: Michael Paquier, Robert Haas
Discussion: https://postgr.es/m/01e3ed3a-8729-5aaa-ca84-e60e3ca59db8@oss.nttdata.com
A manifest is a JSON document which includes (1) the file name, size,
last modification time, and an optional checksum for each file backed
up, (2) timelines and LSNs for whatever WAL will need to be replayed
to make the backup consistent, and (3) a checksum for the manifest
itself. By default, we use CRC-32C when checksumming data files,
because we are trying to detect corruption and user error, not foil an
adversary. However, pg_basebackup and the server-side BASE_BACKUP
command now have options to select a different algorithm, so users
wanting a cryptographic hash function can select SHA-224, SHA-256,
SHA-384, or SHA-512. Users not wanting file checksums at all can
disable them, or disable generating of the backup manifest altogether.
Using a cryptographic hash function in place of CRC-32C consumes
significantly more CPU cycles, which may slow down backups in some
cases.
A new tool called pg_validatebackup can validate a backup against the
manifest. If no checksums are present, it can still check that the
right files exist and that they have the expected sizes. If checksums
are present, it can also verify that each file has the expected
checksum. Additionally, it calls pg_waldump to verify that the
expected WAL files are present and parseable. Only plain format
backups can be validated directly, but tar format backups can be
validated after extracting them.
Robert Haas, with help, ideas, review, and testing from David Steele,
Stephen Frost, Andrew Dunstan, Rushabh Lathia, Suraj Kharage, Tushar
Ahuja, Rajkumar Raghuwanshi, Mark Dilger, Davinder Singh, Jeevan
Chalke, Amit Kapila, Andres Freund, and Noah Misch.
Discussion: http://postgr.es/m/CA+TgmoZV8dw1H2bzZ9xkKwdrk8+XYa+DC9H=F7heO2zna5T6qg@mail.gmail.com
This commit changes pg_basebackup so that it specifies PROGRESS option in
BASE_BACKUP replication command whether --progress is specified or not.
This causes the server to estimate the total backup size and report it in
pg_stat_progress_basebackup.backup_total, by default. This is reasonable
default because the time required for the estimation would not be so large
in most cases.
Also this commit adds new option --no-estimate-size to pg_basebackup.
This option prevents the server from the estimation, and so is useful to
avoid such estimation time if it's too long.
Author: Fujii Masao
Reviewed-by: Magnus Hagander, Amit Langote
Discussion: https://postgr.es/m/CABUevEyDPPSjP7KRvfTXPdqOdY5aWNkqsB5aAXs3bco5ZwtGHg@mail.gmail.com
This reverts commit 7bae0ad, as this is not ideal with the tar format,
and we may want to explore more options like what is done by tar with
some equivalents of --owner and --group, but for pg_basebackup.
Per complaints from Magnus Hagander and Stephen Frost.
Discussion: https://postgr.es/m/20200205172259.GW3195@tamriel.snowman.net
First, this code did not bother checking for a failure when calling
dup(). Then, per zlib, gzerror() returns NULL for a NULL input, which
can happen if passing down to gzdopen() an invalid file descriptor or if
there was an allocation failure.
No back-patch is done as this would unlikely be a problem in the field.
Per Coverity.
Reported-by: Tom Lane
Similarly to pg_upgrade, pg_ctl and initdb, a root user is able to use
--version and --help, but cannot execute the actual operation to avoid
the creation of files with permissions incompatible with the
postmaster.
This is a behavior change, so not back-patching is done.
Author: Ian Barwick
Discussion: https://postgr.es/m/CABvVfJVqOdD2neLkYdygdOHvbWz_5K_iWiqY+psMfA=FeAa3qQ@mail.gmail.com
Add a new function ReceiveCopyData that does just that, taking a
callback as an argument to specify what should be done with each chunk
as it is received. This allows a single copy of the logic to be shared
between ReceiveTarFile and ReceiveAndUnpackTarFile, and eliminates
a few #ifdef conditions based on HAVE_LIBZ.
While this is slightly more code, it's arguably clearer, and
there is a pending patch that introduces additional calls to
ReceiveCopyData.
This commit is not intended to result in any functional change.
Discussion: http://postgr.es/m/CA+TgmoYZDTHbSpwZtW=JDgAhwVAYvmdSrRUjOd+AYdfNNXVBDg@mail.gmail.com
Since the addition of fsync requests in bc34223 to make base backup data
consistent on disk once pg_basebackup finishes, each tablespace tar file
is individually flushed once completed, with an additional flush of the
parent directory when the base backup finishes. While holding a
connection to the server, a fsync request taking a long time may cause a
failure of the base backup, which is annoying for any integration. A
recent example of breakage can involve tcp_user_timeout, but
wal_sender_timeout can cause similar problems.
While reviewing the code, there was a second issue causing too many
fsync requests to be done for the same WAL data. As recursive fsyncs
are done at the end of the backup for both the plain and tar formats
from the base target directory where everything is written, it is fine
to disable fsyncs when fetching or streaming WAL.
Reported-by: Ryohei Takahashi
Author: Michael Paquier
Reviewed-by: Ryohei Takahashi
Discussion: https://postgr.es/m/OSBPR01MB4550DAE2F8C9502894A45AAB82BE0@OSBPR01MB4550.jpnprd01.prod.outlook.com
Backpatch-through: 10
Document that the tablespace sizes are in units of kilobytes. Make
the pg_basebackup source code a bit clearer about this, too.
Reviewed-by: Magnus Hagander <magnus@hagander.net>
Several buildfarm members have been complaining about that with gcc,
like jacana. Weirdly enough, Visual Studio's compilers do not find this
issue.
Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/20190719050830.GK1859@paquier.xyz
The original placement of this module in src/fe_utils/ is ill-considered,
because several src/common/ modules have dependencies on it, meaning that
libpgcommon and libpgfeutils now have mutual dependencies. That makes it
pointless to have distinct libraries at all. The intended design is that
libpgcommon is lower-level than libpgfeutils, so only dependencies from
the latter to the former are acceptable.
We already have the precedent that fe_memutils and a couple of other
modules in src/common/ are frontend-only, so it's not stretching anything
out of whack to treat logging.c as a frontend-only module in src/common/.
To the extent that such modules help provide a common frontend/backend
environment for the rest of common/ to use, it's a reasonable design.
(logging.c does not yet provide an ereport() emulation, but one can
dream.)
Hence, move these files over, and revert basically all of the build-system
changes made by commit cc8d41511. There are no places that need to grow
new dependencies on libpgcommon, further reinforcing the idea that this
is the right solution.
Discussion: https://postgr.es/m/a912ffff-f6e4-778a-c86a-cf5c47a12933@2ndquadrant.com
This unifies the various ad hoc logging (message printing, error
printing) systems used throughout the command-line programs.
Features:
- Program name is automatically prefixed.
- Message string does not end with newline. This removes a common
source of inconsistencies and omissions.
- Additionally, a final newline is automatically stripped, simplifying
use of PQerrorMessage() etc., another common source of mistakes.
- I converted error message strings to use %m where possible.
- As a result of the above several points, more translatable message
strings can be shared between different components and between
frontends and backend, without gratuitous punctuation or whitespace
differences.
- There is support for setting a "log level". This is not meant to be
user-facing, but can be used internally to implement debug or
verbose modes.
- Lazy argument evaluation, so no significant overhead if logging at
some level is disabled.
- Some color in the messages, similar to gcc and clang. Set
PG_COLOR=auto to try it out. Some colors are predefined, but can be
customized by setting PG_COLORS.
- Common files (common/, fe_utils/, etc.) can handle logging much more
simply by just using one API without worrying too much about the
context of the calling program, requiring callbacks, or having to
pass "progname" around everywhere.
- Some programs called setvbuf() to make sure that stderr is
unbuffered, even on Windows. But not all programs did that. This
is now done centrally.
Soft goals:
- Reduces vertical space use and visual complexity of error reporting
in the source code.
- Encourages more deliberate classification of messages. For example,
in some cases it wasn't clear without analyzing the surrounding code
whether a message was meant as an error or just an info.
- Concepts and terms are vaguely aligned with popular logging
frameworks such as log4j and Python logging.
This is all just about printing stuff out. Nothing affects program
flow (e.g., fatal exits). The uses are just too varied to do that.
Some existing code had wrappers that do some kind of print-and-exit,
and I adapted those.
I tried to keep the output mostly the same, but there is a lot of
historical baggage to unwind and special cases to consider, and I
might not always have succeeded. One significant change is that
pg_rewind used to write all error messages to stdout. That is now
changed to stderr.
Reviewed-by: Donald Dong <xdong@csumb.edu>
Reviewed-by: Arthur Zakirov <a.zakirov@postgrespro.ru>
Discussion: https://www.postgresql.org/message-id/flat/6a609b43-4f57-7348-6480-bd022f924310@2ndquadrant.com
When 2dedf4d9 has integrated recovery.conf into postgresql.conf, it also
changed pg_basebackup -R in the way recovery configuration is
generated. However this implementation forgot the fact that
pg_basebackup needs to keep compatibility with older server versions as
well.
Reported-by: Devrim Gündüz
Author: Sergei Kornilov, Michael Paquier
Discussion: https://postgr.es/m/3458f7cd12d74acd90180a671c8d5a081d60e162.camel@gunduz.org
Commit c0d0e54084 replaced the ones in the documentation, but missed out
on the ones in the code. Replace those as well, but unlike c0d0e54084,
don't backpatch the code changes to avoid breaking translations.
At least as far back as the 2008 spec, POSIX has defined strsignal(3)
for looking up descriptive strings for signal numbers. We hadn't gotten
the word though, and were still using the crufty old sys_siglist array,
which is in no standard even though most Unixen provide it.
Aside from not being formally standards-compliant, this was just plain
ugly because it involved #ifdef's at every place using the code.
To eliminate the #ifdef's, create a portability function pg_strsignal,
which wraps strsignal(3) if available and otherwise falls back to
sys_siglist[] if available. The set of Unixen with neither API is
probably empty these days, but on any platform with neither, you'll
just get "unrecognized signal". All extant callers print the numeric
signal number too, so no need to work harder than that.
Along the way, upgrade pg_basebackup's child-error-exit reporting
to match the rest of the system.
Discussion: https://postgr.es/m/25758.1544983503@sss.pgh.pa.us
recovery.conf settings are now set in postgresql.conf (or other GUC
sources). Currently, all the affected settings are PGC_POSTMASTER;
this could be refined in the future case by case.
Recovery is now initiated by a file recovery.signal. Standby mode is
initiated by a file standby.signal. The standby_mode setting is
gone. If a recovery.conf file is found, an error is issued.
The trigger_file setting has been renamed to promote_trigger_file as
part of the move.
The documentation chapter "Recovery Configuration" has been integrated
into "Server Configuration".
pg_basebackup -R now appends settings to postgresql.auto.conf and
creates a standby.signal file.
Author: Fujii Masao <masao.fujii@gmail.com>
Author: Simon Riggs <simon@2ndquadrant.com>
Author: Abhijit Menon-Sen <ams@2ndquadrant.com>
Author: Sergei Kornilov <sk@zsrv.org>
Discussion: https://www.postgresql.org/message-id/flat/607741529606767@web3g.yandex.ru/
This is useful to know when the data copy has been finished. The
current situation can be confusing for users as the last message is
"waiting for background process to finish streaming", so it looks like
this is taking time but the final sync is instead.
Author: Jeff Janes
Discussion: https://postgr.es/m/CAMkU=1ypeoMJ=tFBG8vP13sxEtXd4Pm_x1SqsJdW_RvzpcvN=A@mail.gmail.com
Robert Haas
Michael Paquier
Peter Eisentraut
Amit Kapila
Bruce Momjian
Heikki Linnakangas
Alvaro Herrera
Tom Lane
Fujii Masao
Noah Misch
Magnus Hagander
Peter Eisentraut