There is a non-trivial amount of code that handles ZLIB compression in
pg_receivewal, from basics like the format name, the calculation of the
start streaming position and of course the compression itself, but there
was no automated coverage for it.
This commit introduces a set of conditional tests (if the build supports
ZLIB) to cover the creation of ZLIB-compressed WAL segments, the
handling of the partial, compressed, WAL segments and the compression
operation in itself. Note that there is an extra phase checking the
validity of the generated files by using directly a gzip command, passed
down by the Makefile of pg_receivewal. This part is skipped if the
command cannot be found, something likely going to happen on Windows
with MSVC except if one sets the variable GZIP_PROGRAM in the
environment of the test.
This set of tests will become handy for upcoming patches that add more
options for the compression methods used by pg_receivewal, like LZ4, to
make sure that no existing facilities are broken.
Author: Georgios Kokolatos
Reviewed-by: Gilles Darold, Michael Paquier
Discussion: https://postgr.es/m/07BK3Mk5aEOsTwGaY77qBVyf9GjoEzn8TMgHLyPGfEFPIpTEmoQuP2P4c7teesjSg-LPeUafsp1flnPeQYINMSMB_UpggJDoduB5EDYBqaQ=@protonmail.com
Build farm animals running ancient HPUX and Solaris have a non-standard
sigwait() from draft versions of POSIX, so they didn't like commit
7c09d279. To avoid the problem in general, only try to use sigwait() if
it's declared by <signal.h> and matches the expected declaration. To
select the modern declaration on Solaris (even in non-threaded
programs), move -D_POSIX_PTHREAD_SEMANTICS into the right place to
affect all translation units.
Also fix the error checking. Modern sigwait() doesn't set errno.
Thanks to Tom Lane for help with this.
Discussion: https://postgr.es/m/3187588.1626136248%40sss.pgh.pa.us
Previously, we would send each line as a separate CopyData message.
That's pretty wasteful if the table is narrow, as each CopyData message
has 5 bytes of overhead. For efficiency, buffer up and pack 8 kB of
input data into each CopyData message.
The server also sends each line as a separate CopyData message in COPY TO
STDOUT, and that's similarly wasteful. But that's documented in the FE/BE
protocol description, so changing that would be a wire protocol break.
Reviewed-by: Aleksander Alekseev
Discussion: https://www.postgresql.org/message-id/40b2cec0-d0fb-3191-2ae1-9a3fe16a7e48%40iki.fi
To add support for streaming transactions at prepare time into the
built-in logical replication, we need to do the following things:
* Modify the output plugin (pgoutput) to implement the new two-phase API
callbacks, by leveraging the extended replication protocol.
* Modify the replication apply worker, to properly handle two-phase
transactions by replaying them on prepare.
* Add a new SUBSCRIPTION option "two_phase" to allow users to enable
two-phase transactions. We enable the two_phase once the initial data sync
is over.
We however must explicitly disable replication of two-phase transactions
during replication slot creation, even if the plugin supports it. We
don't need to replicate the changes accumulated during this phase,
and moreover, we don't have a replication connection open so we don't know
where to send the data anyway.
The streaming option is not allowed with this new two_phase option. This
can be done as a separate patch.
We don't allow to toggle two_phase option of a subscription because it can
lead to an inconsistent replica. For the same reason, we don't allow to
refresh the publication once the two_phase is enabled for a subscription
unless copy_data option is false.
Author: Peter Smith, Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Sawada Masahiko, Vignesh C, Dilip Kumar, Takamichi Osumi, Greg Nancarrow
Tested-By: Haiying Tang
Discussion: https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ru
Discussion: https://postgr.es/m/CAA4eK1+opiV4aFTmWWUF9h_32=HfPOW9vZASHarT0UA5oBrtGw@mail.gmail.com
The name introduced by commit 4656e3d66 was agreed to be unreasonably
long. To match this change, rename initdb's recently-added
--clobber-cache option to --discard-caches.
Discussion: https://postgr.es/m/1374320.1625430433@sss.pgh.pa.us
Allow a pager to be used by the \watch command. This works but isn't
very useful with traditional pagers like "less", so use a different
environment variable. The popular open source tool "pspg" (also by
Pavel) knows how to display the output if you set PSQL_WATCH_PAGER="pspg
--stream".
To make \watch react quickly when the user quits the pager or presses
^C, and also to increase the accuracy of its timing and decrease the
rate of useless context switches, change the main loop of the \watch
command to use sigwait() rather than a sleeping/polling loop, on Unix.
Supported on Unix only for now (like pspg).
Author: Pavel Stehule <pavel.stehule@gmail.com>
Author: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CAFj8pRBfzUUPz-3gN5oAzto9SDuRSq-TQPfXU_P6h0L7hO%2BEhg%40mail.gmail.com
This commit removes a dependency to the central logging facilities in
the JSON parsing routines of src/common/, which existed to log errors
when seeing error codes that do not match any existing values in
JsonParseErrorType, which is not something that should never happen.
The routine providing a detailed error message based on the error code
is made backend-only, the existing code being unsafe to use in the
frontend as the error message may finish by being palloc'd or point to a
static string, so there is no way to know if the memory of the message
should be pfree'd or not. The only user of this routine in the frontend
was pg_verifybackup, that is changed to use a more generic error message
on parsing failure.
Note that making this code more resilient to OOM failures if used in
shared libraries would require much more work as a lot of code paths
still rely on palloc() & friends, but we are not sure yet if we need to
go down to that. Still, removing the dependency to logging is a step
toward more portability.
This cleans up the handling of check_stack_depth() while on it, as it
exists only in the backend.
Per discussion with Jacob Champion and Tom Lane.
Discussion: https://postgr.es/m/YNwL7kXwn3Cckbd6@paquier.xyz
Commit 4656e3d66 replaced the "#define CLOBBER_CACHE_ALWAYS"
testing mechanism with a GUC, which has been a great help for
doing cache-clobber testing in more efficient ways; but there
is a gap in the implementation. The only way to do cache-clobber
testing during an initdb run is to use the old method with #define,
because one can't set the GUC from outside. Improve this by
adding a switch to initdb for the purpose.
(Perhaps someday we should let initdb pass through arbitrary
"-c NAME=VALUE" switches. Quoting difficulties dissuaded me
from attempting that right now, though.)
Back-patch to v14 where 4656e3d66 came in.
Discussion: https://postgr.es/m/1582507.1624227029@sss.pgh.pa.us
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
This commit prevents pg_checksums to do a rewrite of a block if it has
no need to, in the case where the computed checksum matches with what's
already stored in the block read. This is helpful to accelerate
successive runs of the tool when the previous ones got interrupted, for
example.
The number of blocks and files written is tracked and reported by the
tool once finished. Note that the final flush of the data folder
happens even if no blocks are written, as it could be possible that a
previous interrupted run got stopped while doing a flush.
Author: Greg Sabino Mullane
Reviewed-by: Paquier Michael, Julien Rouhaud
Discussion: https://postgr.es/m/CAKAnmmL+k6goxmVzQJB+0bAR0PN1sgo6GDUXJhyhUmVMze1QAw@mail.gmail.com
The behavior changed sometime after Perl 5.8.9, and "man perlre" says it
"may lead to confusing results." Per buildfarm member gaur. This
repairs commit a7a7be1f2fa6b9f0f48e69f12256d8f588af729b.
Discussion: https://postgr.es/m/20210629053627.GA2061079@rfd.leadboat.com
The logic is implemented so as there can be a choice in the compression
used when building a WAL record, and an extra per-record bit is used to
track down if a block is compressed with PGLZ, LZ4 or nothing.
wal_compression, the existing parameter, is changed to an enum with
support for the following backward-compatible values:
- "off", the default, to not use compression.
- "pglz" or "on", to compress FPWs with PGLZ.
- "lz4", the new mode, to compress FPWs with LZ4.
Benchmarking has showed that LZ4 outclasses easily PGLZ. ZSTD would be
also an interesting choice, but going just with LZ4 for now makes the
patch minimalistic as toast compression is already able to use LZ4, so
there is no need to worry about any build-related needs for this
implementation.
Author: Andrey Borodin, Justin Pryzby
Reviewed-by: Dilip Kumar, Michael Paquier
Discussion: https://postgr.es/m/3037310D-ECB7-4BF1-AF20-01C10BB33A33@yandex-team.ru
As we do for other attributes of the public schema, omit the COMMENT
command when its payload would match what initdb had installed. For
dumps that do carry this new COMMENT command, non-superusers restoring
them are likely to get an error.
Reviewed by Asif Rehman.
Discussion: https://postgr.es/m/ab48a34c-60f6-e388-502a-3e5fe46a2dae@postgresfriends.org
Instead use the common/int.h functions to check for integer overflow
in a more C-standard-compliant fashion. This is motivated by recent
failures on buildfarm member moonjelly, where it appears that
development-tip gcc is optimizing without regard to the -fwrapv
switch. Presumably that's a gcc bug that will be fixed soon, but
we might as well install cleaner coding here rather than wait.
(This does not address the question of whether we'll ever be able
to get rid of using -fwrapv. Testing shows that this spot is the
only place where doing so creates visible regression test failures,
but unfortunately that proves very little.)
Back-patch to v12. The common/int.h functions exist in v11, but
that branch doesn't use them in any client-side code. I judge
that this case isn't interesting enough in the real world to take
even a small risk of issues from being the first such use.
Tom Lane and Fabien Coelho
Discussion: https://postgr.es/m/73927.1624815543@sss.pgh.pa.us
002_pgbench_no_server was printing some array pointers instead of the
actual contents of those arrays for the expected outputs of stdout and
stderr for a tested command. This does not add any new information that
can help with debugging as the test names allow to track failure
locations, if any.
This commit simply removes those logs as the rest of the printed
information is redundant with command_checks_all().
Per discussion with Andrew Dunstan and Álvaro Herrera.
Discussion: https://postgr.es/m/YNXNFaG7IgkzZanD@paquier.xyz
Backpatch-through: 11
This fixes a couple of problems within the so-said code of this commit
subject:
- Replace the use of open() with slurp_file(), fixing an issue reported
by buildfarm member fairywren whose perl installation keep around CRLF
characters, causing the matching patterns for the logs to fail.
- Remove the eval block, which is not really necessary.
This set of issues has come into light after fixing a different issue
with c13585fe, and this is wrong since this code has been introduced.
Reported-by: Andrew Dunstan, and buildfarm member fairywren
Author: Michael Paquier
Reviewed-by: Andrew Dunstan
Discussion: https://postgr.es/m/0f49303e-7784-b3ee-200b-cbf67be2eb9e@dunslane.net
Backpatch-through: 11
fairywren is not happy with the pattern checks introduced by c13585f.
I am not sure if this outlines a bug in pgbench or if the regex patterns
used in the tests are too restrictive for this buildfarm member's
environment. This adds more debugging information to show the log
entries that do not match with the expected pattern, to help in finding
out what's happening. That seems like a good addition in the long-term
anyway as that may not be the only issue in this area.
Discussion: https://postgr.es/m/YNUad2HvgW+6eXyo@paquier.xyz
The logic checking for the format of per-thread logs used grep() with
directly "$re", which would cause the test to consider all the logs as
a match without caring about their format at all. Using "/$re/" makes
grep() perform a regex test, which is what we want here.
While on it, improve some of the tests to be more picky with the
patterns expected and add more comments to describe the tests.
Issue discovered while digging into a separate patch.
Author: Fabien Coelho, Michael Paquier
Discussion: https://postgr.es/m/YNPsPAUoVDCpPOGk@paquier.xyz
Backpatch-through: 11
Generalize the INDEX_CLEANUP VACUUM parameter (and the corresponding
reloption): make it into a ternary style boolean parameter. It now
exposes a third option, "auto". The "auto" option (which is now the
default) enables the "bypass index vacuuming" optimization added by
commit 1e55e7d1.
"VACUUM (INDEX_CLEANUP TRUE)" is redefined to once again make VACUUM
simply do any required index vacuuming, regardless of how few dead
tuples are encountered during the first scan of the target heap relation
(unless there are exactly zero). This gives users a way of opting out
of the "bypass index vacuuming" optimization, if for whatever reason
that proves necessary. It is also expected to be used by PostgreSQL
developers as a testing option from time to time.
"VACUUM (INDEX_CLEANUP FALSE)" does the same thing as it always has: it
forcibly disables both index vacuuming and index cleanup. It's not
expected to be used much in PostgreSQL 14. The failsafe mechanism added
by commit 1e55e7d1 addresses the same problem in a simpler way.
INDEX_CLEANUP can now be thought of as a testing and compatibility
option.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-By: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/CAH2-WznrBoCST4_Gxh_G9hA8NzGUbeBGnOUC8FcXcrhqsv6OHQ@mail.gmail.com
Commit 547f04e73 caused pgbench to start printing its version number,
which seems like a fine idea, but it needs a bit more work:
* Print the server version number too, when different.
* Print the PG_VERSION string, not some reconstructed approximation.
This patch copies psql's well-tested code for the same purpose.
Discussion: https://postgr.es/m/1226654.1624036821@sss.pgh.pa.us
Recent glibc versions have made mktime() fail if tm_isdst is
inconsistent with the prevailing timezone; in particular it fails for
tm_isdst = 1 when the zone is UTC. (This seems wildly inconsistent
with the POSIX-mandated treatment of "incorrect" values for the other
fields of struct tm, so if you ask me it's a bug, but I bet they'll
say it's intentional.) This has been observed to cause cosmetic
problems when pg_restore'ing an archive created in a different
timezone.
To fix, do mktime() using the field values from the archive, and if
that fails try again with tm_isdst = -1. This will give a result
that's off by the UTC-offset difference from the original zone, but
that was true before, too. It's not terribly critical since we don't
do anything with the result except possibly print it. (Someday we
should flush this entire bit of logic and record a standard-format
timestamp in the archive instead. That's not okay for a back-patched
bug fix, though.)
Also, guard our only other use of mktime() by having initdb's
build_time_t() set tm_isdst = -1 not 0. This case could only have
an issue in zones that are DST year-round; but I think some do exist,
or could in future.
Per report from Wells Oliver. Back-patch to all supported
versions, since any of them might need to run with a newer glibc.
Discussion: https://postgr.es/m/CAOC+FBWDhDHO7G-i1_n_hjRzCnUeFO+H-Czi1y10mFhRWpBrew@mail.gmail.com
We've accumulated quite a mix of instances of "an SQL" and "a SQL" in the
documents. It would be good to be a bit more consistent with these.
The most recent version of the SQL standard I looked at seems to prefer
"an SQL". That seems like a good lead to follow, so here we change all
instances of "a SQL" to become "an SQL". Most instances correctly use
"an SQL" already, so it also makes sense to use the dominant variation in
order to minimise churn.
Additionally, there were some other abbreviations that needed to be
adjusted. FSM, SSPI, SRF and a few others. Also fix some pronounceable,
abbreviations to use "a" instead of "an". For example, "a SASL" instead
of "an SASL".
Here I've only adjusted the documents and error messages. Many others
still exist in source code comments. Translator hint comments seem to be
the biggest culprit. It currently does not seem worth the churn to change
these.
Discussion: https://postgr.es/m/CAApHDvpML27UqFXnrYO1MJddsKVMQoiZisPvsAGhKE_tsKXquw%40mail.gmail.com
Commit 2453ea142 redefined pg_proc.proargtypes to include the types of
OUT parameters, for procedures only. While that had some advantages
for implementing the SQL-spec behavior of DROP PROCEDURE, it was pretty
disastrous from a number of other perspectives. Notably, since the
primary key of pg_proc is name + proargtypes, this made it possible to
have multiple procedures with identical names + input arguments and
differing output argument types. That would make it impossible to call
any one of the procedures by writing just NULL (or "?", or any other
data-type-free notation) for the output argument(s). The change also
seems likely to cause grave confusion for client applications that
examine pg_proc and expect the traditional definition of proargtypes.
Hence, revert the definition of proargtypes to what it was, and
undo a number of complications that had been added to support that.
To support the SQL-spec behavior of DROP PROCEDURE, when there are
no argmode markers in the command's parameter list, we perform the
lookup both ways (that is, matching against both proargtypes and
proallargtypes), succeeding if we get just one unique match.
In principle this could result in ambiguous-function failures
that would not happen when using only one of the two rules.
However, overloading of procedure names is thought to be a pretty
rare usage, so this shouldn't cause many problems in practice.
Postgres-specific code such as pg_dump can defend against any
possibility of such failures by being careful to specify argmodes
for all procedure arguments.
This also fixes a few other bugs in the area of CALL statements
with named parameters, and improves the documentation a little.
catversion bump forced because the representation of procedures
with OUT arguments changes.
Discussion: https://postgr.es/m/3742981.1621533210@sss.pgh.pa.us
The set of subcommands supported by \dAp, \do and \dy was described
incorrectly in psql's --help. The documentation was already consistent
with the code.
Reported-by: inoas, from IRC
Author: Matthijs van der Vleuten
Reviewed-by: Neil Chen
Discussion: https://postgr.es/m/6a984e24-2171-4039-9050-92d55e7b23fe@www.fastmail.com
Backpatch-through: 9.6
An incorrectly-encoded multibyte character near the end of a string
could cause various processing loops to run past the string's
terminating NUL, with results ranging from no detectable issue to
a program crash, depending on what happens to be in the following
memory.
This isn't an issue in the server, because we take care to verify
the encoding of strings before doing any interesting processing
on them. However, that lack of care leaked into client-side code
which shouldn't assume that anyone has validated the encoding of
its input.
Although this is certainly a bug worth fixing, the PG security team
elected not to regard it as a security issue, primarily because
any untrusted text should be sanitized by PQescapeLiteral or
the like before being incorporated into a SQL or psql command.
(If an app fails to do so, the same technique can be used to
cause SQL injection, with probably much more dire consequences
than a mere client-program crash.) Those functions were already
made proof against this class of problem, cf CVE-2006-2313.
To fix, invent PQmblenBounded() which is like PQmblen() except it
won't return more than the number of bytes remaining in the string.
In HEAD we can make this a new libpq function, as PQmblen() is.
It seems imprudent to change libpq's API in stable branches though,
so in the back branches define PQmblenBounded as a macro in the files
that need it. (Note that just changing PQmblen's behavior would not
be a good idea; notably, it would completely break the escaping
functions' defense against this exact problem. So we just want a
version for those callers that don't have any better way of handling
this issue.)
Per private report from houjingyi. Back-patch to all supported branches.
The previous arrangement was just one big list, and the internal order
was not all consistent either. Now arrange the options by group and
sort them, the way it's already done in the --help output and one
other reference pages. Also fix some ordering in the --help output.
Fix a few places that were using appendStringInfo() when they should have
been using appendStringInfoString(). Also some cases of
appendPQExpBuffer() that would have been better suited to use
appendPQExpBufferChar(), and finally, some places that used
appendPQExpBuffer() when appendPQExpBufferStr() would have suited better.
There are no bugs are being fixed here. The aim is just to make the code
use the most optimal function for the job.
All the code being changed here is new to PG14. It makes sense to fix
these before we branch for PG15. There are a few other places that we
could fix, but those cases are older code so fixing those seems less
worthwhile as it may cause unnecessary back-patching pain in the future.
Author: Hou Zhijie
Discussion: https://postgr.es/m/OS0PR01MB5716732158B1C4142C6FE375943D9@OS0PR01MB5716.jpnprd01.prod.outlook.com
Redefine '\0' (InvalidCompressionMethod) as meaning "if we need to
compress, use the current setting of default_toast_compression".
This allows '\0' to be a suitable default choice regardless of
datatype, greatly simplifying code paths that initialize tupledescs
and the like. It seems like a more user-friendly approach as well,
because now the default compression choice doesn't migrate into table
definitions, meaning that changing default_toast_compression is
usually sufficient to flip an installation's behavior; one needn't
tediously issue per-column ALTER SET COMPRESSION commands.
Along the way, fix a few minor bugs and documentation issues
with the per-column-compression feature. Adopt more robust
APIs for SetIndexStorageProperties and GetAttributeCompression.
Bump catversion because typical contents of attcompression will now
be different. We could get away without doing that, but it seems
better to ensure v14 installations all agree on this. (We already
forced initdb for beta2, anyway.)
Discussion: https://postgr.es/m/626613.1621787110@sss.pgh.pa.us
The error messages, docs, and one of the options were using
'parallel degree' to indicate parallelism used by vacuum command. We
normally use 'parallel workers' at other places so change it for parallel
vacuum accordingly.
Author: Bharath Rupireddy
Reviewed-by: Dilip Kumar, Amit Kapila
Backpatch-through: 13
Discussion: https://postgr.es/m/CALj2ACWz=PYrrFXVsEKb9J1aiX4raA+UBe02hdRp_zqDkrWUiw@mail.gmail.com
"typename" is a C++ keyword, so pg_upgrade.h fails to compile in C++.
Fortunately, there seems no likely reason for somebody to need to
do that. Nonetheless, it's project policy that all .h files should
pass cpluspluscheck, so rename the argument to fix that.
Oversight in 57c081de0; back-patch as that was. (The policy requiring
pg_upgrade.h to pass cpluspluscheck only goes back to v12, but it
seems best to keep this code looking the same in all branches.)
One of the tests for the pgbench permute() function added by
6b258e3d68 fails on some 32-bit platforms, due to variations in the
floating point computations in getrand(). The remaining tests give
sufficient coverage, so just remove the failing test.
Reported by Christoph Berg. Analysis by Thomas Munro and Tom Lane.
Based on patch by Fabien Coelho.
Discussion: https://postgr.es/m/YKQnUoYV63GRJBDD@msg.df7cb.de
This is an oversight from bbe0a81d, where the equivalent option exists
in pg_dump. This is useful to be able to reset the compression methods
cluster-wide when restoring the data based on default_toast_compression.
Reviewed-by: Daniel Gustafsson, Tom Lane
Discussion: https://postgr.es/m/YKHC+qCJvzCRVCpY@paquier.xyz
When specified directly as DML queries, INSERT was not getting always
completed to "INSERT INTO", same for DELETE with "DELETE FROM". This
makes the completion behavior more consistent for both commands, saving
a few keystrokes.
Commands on policies, triggers, grant/revoke, etc. require only DELETE
as completion keyword.
Author: Haiying Tang
Reviewed-by: Dilip Kumar, Julien Rouhaud
Discussion: https://postgr.es/m/OS0PR01MB61135AE2B07CCD1AB8C6A0F6FB549@OS0PR01MB6113.jpnprd01.prod.outlook.com
Also "make reformat-dat-files".
The only change worthy of note is that pgindent messed up the formatting
of launcher.c's struct LogicalRepWorkerId, which led me to notice that
that struct wasn't used at all anymore, so I just took it out.
This set of commits has some bugs with known fixes, but at this late
stage in the release cycle it seems best to revert and resubmit next
time, along with some new automated test coverage for this whole area.
Commits reverted:
dc88460c: Doc: Review for "Optionally prefetch referenced data in recovery."
1d257577: Optionally prefetch referenced data in recovery.
f003d9f8: Add circular WAL decoding buffer.
323cbe7c: Remove read_page callback from XLogReader.
Remove the new GUC group WAL_RECOVERY recently added by a55a9847, as the
corresponding section of config.sgml is now reverted.
Discussion: https://postgr.es/m/CAOuzzgrn7iKnFRsB4MHp3UisEQAGgZMbk_ViTN4HV4-Ksq8zCg%40mail.gmail.com
Some relations with LZ4 used as the toast compression methods have been
left around in the main regression test suite to stress pg_upgrade, but
pg_dump, that includes tests much more picky in terms of output
generated, had no actual coverage with this feature.
Similarly to collations, tests only working with LZ4 are tracked with an
additional flag, and this uses TestLib::check_pg_config() to check if
the build supports LZ4 or not. This stresses more scenarios with
tables, materialized views and pg_dump --no-toast-compression.
Author: Dilip Kumar
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAFiTN-twgPmohG7qj1HXhySq16h123y5OowsQR+5h1YeZE9fmQ@mail.gmail.com