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2024-08-30Clarify restrict_nonsystem_relation_kind description.Masahiko Sawada
This change improves the description of the restrict_nonsystem_relation_kind parameter in guc_table.c and the documentation for better clarity. Backpatch to 12, where this GUC parameter was introduced. Reviewed-by: Peter Eisentraut Discussion: https://postgr.es/m/6a96f1af-22b4-4a80-8161-1f26606b9ee2%40eisentraut.org Backpatch-through: 12
2024-08-10Allow adjusting session_authorization and role in parallel workers.Tom Lane
The code intends to allow GUCs to be set within parallel workers via function SET clauses, but not otherwise. However, doing so fails for "session_authorization" and "role", because the assign hooks for those attempt to set the subsidiary "is_superuser" GUC, and that call falls foul of the "not otherwise" prohibition. We can't switch to using GUC_ACTION_SAVE for this, so instead add a new GUC variable flag GUC_ALLOW_IN_PARALLEL to mark is_superuser as being safe to set anyway. (This is okay because is_superuser has context PGC_INTERNAL and thus only hard-wired calls can change it. We'd need more thought before applying the flag to other GUCs; but maybe there are other use-cases.) This isn't the prettiest fix perhaps, but other alternatives we thought of would be much more invasive. While here, correct a thinko in commit 059de3ca4: when rejecting a GUC setting within a parallel worker, we should return 0 not -1 if the ereport doesn't longjmp. (This seems to have no consequences right now because no caller cares, but it's inconsistent.) Improve the comments to try to forestall future confusion of the same kind. Despite the lack of field complaints, this seems worth back-patching. Thanks to Nathan Bossart for the idea to invent a new flag, and for review. Discussion: https://postgr.es/m/2833457.1723229039@sss.pgh.pa.us
2024-08-05Restrict accesses to non-system views and foreign tables during pg_dump.Masahiko Sawada
When pg_dump retrieves the list of database objects and performs the data dump, there was possibility that objects are replaced with others of the same name, such as views, and access them. This vulnerability could result in code execution with superuser privileges during the pg_dump process. This issue can arise when dumping data of sequences, foreign tables (only 13 or later), or tables registered with a WHERE clause in the extension configuration table. To address this, pg_dump now utilizes the newly introduced restrict_nonsystem_relation_kind GUC parameter to restrict the accesses to non-system views and foreign tables during the dump process. This new GUC parameter is added to back branches too, but these changes do not require cluster recreation. Back-patch to all supported branches. Reviewed-by: Noah Misch Security: CVE-2024-7348 Backpatch-through: 12
2024-07-15Fix bad indentation introduced in 43cd30bcd1cAndres Freund
Oops. Reported-by: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://postgr.es/m/ZpVZB9rH5tHllO75@nathan Backpatch: 12-, like 43cd30bcd1c
2024-07-15Fix type confusion in guc_var_compare()Andres Freund
Before this change guc_var_compare() cast the input arguments to const struct config_generic *. That's not quite right however, as the input on one side is often just a char * on one side. Instead just use char *, the first field in config_generic. This fixes a -Warray-bounds warning with some versions of gcc. While the warning is only known to be triggered for <= 15, the issue the warning points out seems real, so apply the fix everywhere. Author: Nazir Bilal Yavuz <byavuz81@gmail.com> Reported-by: Erik Rijkers <er@xs4all.nl> Suggested-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/a74a1a0d-0fd2-3649-5224-4f754e8f91aa%40xs4all.nl
2024-03-26Allow "make check"-style testing to work with musl C library.Tom Lane
The musl dynamic linker saves a pointer to the process' environment value of LD_LIBRARY_PATH very early in startup. When we move/clobber the environment to make more room for ps status strings, we clobber that value and thereby prevent libraries from being found via LD_LIBRARY_PATH, which breaks the use of a temporary installation for testing purposes. To fix, stop collecting usable space for ps status if we notice that the variable we are about to clobber is LD_LIBRARY_PATH. This will result in some reduction in how long the ps status can be, but it's only likely to occur in temporary test contexts, so it doesn't seem like a big problem. In any case, we don't have to do it if we see we are on glibc, which surely is where the majority of our Linux testing is done. Thomas Munro, Bruce Momjian, and Tom Lane, per report from Wolfgang Walther. Back-patch to all supported branches, with the hope that we'll set up a buildfarm animal to test on this platform. Discussion: https://postgr.es/m/fddd1cd6-dc16-40a2-9eb5-d7fef2101488@technowledgy.de
2024-02-15Doc: improve a couple of comments in postgresql.conf.sample.Tom Lane
Clarify comments associated with max_parallel_workers and related settings. Per bug #18343 from Christopher Kline. Discussion: https://postgr.es/m/18343-3a5e903d1d3692ab@postgresql.org
2023-12-26Fix failure to verify PGC_[SU_]BACKEND GUCs in pg_file_settings view.Tom Lane
set_config_option() bails out early if it detects that the option to be set is PGC_BACKEND or PGC_SU_BACKEND class and we're reading the config file in a postmaster child; we don't want to apply any new value in such a case. That's fine as far as it goes, but it fails to consider the requirements of the pg_file_settings view: for that, we need to check validity of the value even though we have no intention to apply it. Because we didn't, even very silly values for affected GUCs would be reported as valid by the view. There are only half a dozen such GUCs, which perhaps explains why this got overlooked for so long. Fix by continuing when changeVal is false; this parallels the logic in some other early-exit paths. Also, the check added by commit 924bcf4f1 to prevent GUC changes in parallel workers seems a few bricks shy of a load: it's evidently assuming that ereport(elevel, ...) won't return. Make sure we bail out if it does. The lack of trouble reports suggests that this is only a latent bug, i.e. parallel workers don't actually reach here with elevel < ERROR. (Per the code coverage report, we never reach here at all in the regression suite.) But we clearly don't want to risk proceeding if that does happen. Per report from Rıdvan Korkmaz. These are ancient bugs, so back-patch to all supported branches. Discussion: https://postgr.es/m/2089235.1703617353@sss.pgh.pa.us
2023-11-10Ensure we use the correct spelling of "ensure"David Rowley
We seem to have accidentally used "insure" in a few places. Correct that. Author: Peter Smith Discussion: https://postgr.es/m/CAHut+Pv0biqrhA3pMhu40aDsj343mTsD75khKnHsLqR8P04f=Q@mail.gmail.com Backpatch-through: 12, oldest supported version
2023-11-02Be more wary about NULL values for GUC string variables.Tom Lane
get_explain_guc_options() crashed if a string GUC marked GUC_EXPLAIN has a NULL boot_val. Nosing around found a couple of other places that seemed insufficiently cautious about NULL string values, although those are likely unreachable in practice. Add some commentary defining the expectations for NULL values of string variables, in hopes of forestalling future additions of more such bugs. Xing Guo, Aleksander Alekseev, Tom Lane Discussion: https://postgr.es/m/CACpMh+AyDx5YUpPaAgzVwC1d8zfOL4JoD-uyFDnNSa1z0EsDQQ@mail.gmail.com
2023-10-16Acquire ControlFileLock in relevant SQL functions.Thomas Munro
Commit dc7d70ea added functions that read the control file, but didn't acquire ControlFileLock. With unlucky timing, file systems that have weak interlocking like ext4 and ntfs could expose partially overwritten contents, and the checksum would fail. Back-patch to all supported releases. Reviewed-by: David Steele <david@pgmasters.net> Reviewed-by: Anton A. Melnikov <aamelnikov@inbox.ru> Reviewed-by: Michael Paquier <michael@paquier.xyz> Discussion: https://postgr.es/m/20221123014224.xisi44byq3cf5psi%40awork3.anarazel.de
2023-01-19Add missing assign hook for GUC checkpoint_completion_targetMichael Paquier
This is wrong since 88e9823, that has switched the WAL sizing configuration from checkpoint_segments to min_wal_size and max_wal_size. This missed the recalculation of the internal value of the internal "CheckPointSegments", that works as a mapping of the old GUC checkpoint_segments, on reload, for example, and it controls the timing of checkpoints depending on the volume of WAL generated. Most users tend to leave checkpoint_completion_target at 0.9 to smooth the I/O workload, which is why I guess this has gone unnoticed for so long, still it can be useful to tweak and reload the value dynamically in some cases to control the timing of checkpoints. Author: Bharath Rupireddy Discussion: https://postgr.es/m/CALj2ACXgPPAm28mruojSBno+F_=9cTOOxHAywu_dfZPeBdybQw@mail.gmail.com Backpatch-through: 11
2022-07-27Allow "in place" tablespaces.Alvaro Herrera
This is a backpatch to branches 10-14 of the following commits: 7170f2159fb2 Allow "in place" tablespaces. c6f2f01611d4 Fix pg_basebackup with in-place tablespaces. f6f0db4d6240 Fix pg_tablespace_location() with in-place tablespaces 7a7cd84893e0 doc: Remove mention to in-place tablespaces for pg_tablespace_location() 5344723755bd Remove unnecessary Windows-specific basebackup code. In-place tablespaces were introduced as a testing helper mechanism, but they are going to be used for a bugfix in WAL replay to be backpatched to all stable branches. I (Álvaro) had to adjust some code to account for lack of get_dirent_type() in branches prior to 14. Author: Thomas Munro <thomas.munro@gmail.com> Author: Michaël Paquier <michael@paquier.xyz> Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/20220722081858.omhn2in5zt3g4nek@alvherre.pgsql
2022-05-31Ensure ParseTzFile() closes the input file after failing.Tom Lane
We hadn't noticed this because (a) few people feed invalid timezone abbreviation files to the server, and (b) in typical scenarios guc.c would throw ereport(ERROR) and then transaction abort handling would silently clean up the leaked file reference. However, it was possible to observe file leakage warnings if one breaks an already-active abbreviation file, because guc.c does not throw ERROR when loading supposedly-validated settings during session start or SIGHUP processing. Report and fix by Kyotaro Horiguchi (cosmetic adjustments by me) Discussion: https://postgr.es/m/20220530.173740.748502979257582392.horikyota.ntt@gmail.com
2022-05-28Handle NULL for short descriptions of custom GUC variablesMichael Paquier
If a short description is specified as NULL in one of the various DefineCustomXXXVariable() functions available to external modules to define a custom parameter, SHOW ALL would crash. This change teaches SHOW ALL to properly handle NULL short descriptions, as well as any code paths that manipulate it, to gain in flexibility. Note that help_config.c was already able to do that, when describing a set of GUCs for postgres --describe-config. Author: Steve Chavez Reviewed by: Nathan Bossart, Andres Freund, Michael Paquier, Tom Lane Discussion: https://postgr.es/m/CAGRrpzY6hO-Kmykna_XvsTv8P2DshGiU6G3j8yGao4mk0CqjHA%40mail.gmail.com Backpatch-through: 10
2022-03-27Fix breakage of get_ps_display() in the PS_USE_NONE case.Tom Lane
Commit 8c6d30f21 caused this function to fail to set *displen in the PS_USE_NONE code path. If the variable's previous value had been negative, that'd lead to a memory clobber at some call sites. We'd managed not to notice due to very thin test coverage of such configurations, but this appears to explain buildfarm member lorikeet's recent struggles. Credit to Andrew Dunstan for spotting the problem. Back-patch to v13 where the bug was introduced. Discussion: https://postgr.es/m/136102.1648320427@sss.pgh.pa.us
2022-03-23Don't try to translate NULL in GetConfigOptionByNum().Andres Freund
Noticed via -fsanitize=undefined. Introduced when a few columns in GetConfigOptionByNum() / pg_settings started to be translated in 72be8c29a / PG 12. Backpatch to all affected branches, for the same reasons as 46ab07ffda9. Discussion: https://postgr.es/m/20220323173537.ll7klrglnp4gn2um@alap3.anarazel.de Backpatch: 12-
2021-07-27Set pg_setting.pending_restart when pertinent config lines are removedAlvaro Herrera
This changes the behavior of examining the pg_file_settings view after changing a config option that requires restart. The user needs to know that any change of such options does not take effect until a restart, and this worked correctly if the line is edited without removing it. However, for the case where the line is removed altogether, the flag doesn't get set, because a flag was only set in set_config_option, but that's not called for lines removed. Repair. (Ref.: commits 62d16c7fc561 and a486e35706ea) Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Daniel Gustafsson <daniel@yesql.se> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/202107262302.xsfdfc5sb7sh@alvherre.pgsql
2021-07-21Document "B" and "us" as accepted units in postgres.conf.sampleJohn Naylor
In postgresql.conf, memory and file size GUCs can be specified with "B" (bytes) as of b06d8e58b. Likewise, time GUCs can be specified with "us" (microseconds) as of caf626b2c. Update postgres.conf.sample to reflect that fact. Pavel Luzanov Backpatch to v12, which is the earliest version that allows both of these units. A separate commit will document the "B" case for v11. Discussion: https://www.postgresql.org/message-id/flat/f10d16fc-8fa0-1b3c-7371-cb3a35a13b7a%40postgrespro.ru
2021-04-13Fix some inappropriately-disallowed uses of ALTER ROLE/DATABASE SET.Tom Lane
Most GUC check hooks that inspect database state have special checks that prevent them from throwing hard errors for state-dependent issues when source == PGC_S_TEST. This allows, for example, "ALTER DATABASE d SET default_text_search_config = foo" when the "foo" configuration hasn't been created yet. Without this, we have problems during dump/reload or pg_upgrade, because pg_dump has no idea about possible dependencies of GUC values and can't ensure a safe restore ordering. However, check_role() and check_session_authorization() hadn't gotten the memo about that, and would throw hard errors anyway. It's not entirely clear what is the use-case for "ALTER ROLE x SET role = y", but we've now heard two independent complaints about that bollixing an upgrade, so apparently some people are doing it. Hence, fix these two functions to act more like other check hooks with similar needs. (But I did not change their insistence on being inside a transaction, as it's still not apparent that setting either GUC from the configuration file would be wise.) Also fix check_temp_buffers, which had a different form of the disease of making state-dependent checks without any exception for PGC_S_TEST. A cursory survey of other GUC check hooks did not find any more issues of this ilk. (There are a lot of interdependencies among PGC_POSTMASTER and PGC_SIGHUP GUCs, which may be a bad idea, but they're not relevant to the immediate concern because they can't be set via ALTER ROLE/DATABASE.) Per reports from Charlie Hornsby and Nathan Bossart. Back-patch to all supported branches. Discussion: https://postgr.es/m/HE1P189MB0523B31598B0C772C908088DB7709@HE1P189MB0523.EURP189.PROD.OUTLOOK.COM Discussion: https://postgr.es/m/20160711223641.1426.86096@wrigleys.postgresql.org
2021-04-09Fix typoMagnus Hagander
Author: Daniel Westermann Backpatch-through: 9.6 Discussion: https://postgr.es/m/GV0P278MB0483A7AA85BAFCC06D90F453D2739@GV0P278MB0483.CHEP278.PROD.OUTLOOK.COM
2021-03-18Don't leak malloc'd strings when a GUC setting is rejected.Tom Lane
Because guc.c prefers to keep all its string values in malloc'd not palloc'd storage, it has to be more careful than usual to avoid leaks. Error exits out of string GUC hook checks failed to clear the proposed value string, and error exits out of ProcessGUCArray() failed to clear the malloc'd results of ParseLongOption(). Found via valgrind testing. This problem is ancient, so back-patch to all supported branches. Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
2021-02-22Remove outdated reference to RAID spindles.Thomas Munro
Commit b09ff536 left behind some outdated advice in the long_desc field of the GUC "effective_io_concurrency". Remove it. Back-patch to 13. Reported-by: Andrew Gierth <andrew@tao11.riddles.org.uk> Reviewed-by: Julien Rouhaud <rjuju123@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKGJyyWqFBxL9gEj-qtjBThGjhAOBE8GBnF8MUJOJ3vrfag%40mail.gmail.com
2021-02-15Default to wal_sync_method=fdatasync on FreeBSD.Thomas Munro
FreeBSD 13 gained O_DSYNC, which would normally cause wal_sync_method to choose open_datasync as its default value. That may not be a good choice for all systems, and performs worse than fdatasync in some scenarios. Let's preserve the existing default behavior for now. Like commit 576477e73c4, which did the same for Linux, back-patch to all supported releases. Discussion: https://postgr.es/m/CA%2BhUKGLsAMXBQrCxCXoW-JsUYmdOL8ALYvaX%3DCrHqWxm-nWbGA%40mail.gmail.com
2020-12-30Fix up usage of krb_server_keyfile GUC parameter.Tom Lane
secure_open_gssapi() installed the krb_server_keyfile setting as KRB5_KTNAME unconditionally, so long as it's not empty. However, pg_GSS_recvauth() only installed it if KRB5_KTNAME wasn't set already, leading to a troubling inconsistency: in theory, clients could see different sets of server principal names depending on whether they use GSSAPI encryption. Always using krb_server_keyfile seems like the right thing, so make both places do that. Also fix up secure_open_gssapi()'s lack of a check for setenv() failure --- it's unlikely, surely, but security-critical actions are no place to be sloppy. Also improve the associated documentation. This patch does nothing about secure_open_gssapi()'s use of setenv(), and indeed causes pg_GSS_recvauth() to use it too. That's nominally against project portability rules, but since this code is only built with --with-gssapi, I do not feel a need to do something about this in the back branches. A fix will be forthcoming for HEAD though. Back-patch to v12 where GSSAPI encryption was introduced. The dubious behavior in pg_GSS_recvauth() goes back further, but it didn't have anything to be inconsistent with, so let it be. Discussion: https://postgr.es/m/2187460.1609263156@sss.pgh.pa.us
2020-12-23Fix portability issues with parsing of recovery_target_xidMichael Paquier
The parsing of this parameter has been using strtoul(), which is not portable across platforms. On most Unix platforms, unsigned long has a size of 64 bits, while on Windows it is 32 bits. It is common in recovery scenarios to rely on the output of txid_current() or even the newer pg_current_xact_id() to get a transaction ID for setting up recovery_target_xid. The value returned by those functions includes the epoch in the computed result, which would cause strtoul() to fail where unsigned long has a size of 32 bits once the epoch is incremented. WAL records and 2PC data include only information about 32-bit XIDs and it is not possible to have XIDs across more than one epoch, so discarding the high bits from the transaction ID set has no impact on recovery. On the contrary, the use of strtoul() prevents a consistent behavior across platforms depending on the size of unsigned long. This commit changes the parsing of recovery_target_xid to use pg_strtouint64() instead, available down to 9.6. There is one TAP test stressing recovery with recovery_target_xid, where a tweak based on pg_reset{xlog,wal} is added to bump the XID epoch so as this change gets tested, as per an idea from Alexander Lakhin. Reported-by: Alexander Lakhin Discussion: https://postgr.es/m/16780-107fd0c0385b1035@postgresql.org Backpatch-through: 9.6
2020-10-12Fix memory leak when guc.c decides a setting can't be applied now.Tom Lane
The prohibitValueChange code paths in set_config_option(), which are executed whenever we re-read a PGC_POSTMASTER variable from postgresql.conf, neglected to free anything before exiting. Thus we'd leak the proposed new value of a PGC_STRING variable, as noted by BoChen in bug #16666. For all variable types, if the check hook creates an "extra" chunk, we'd also leak that. These are malloc not palloc chunks, so there is no mechanism for recovering the leaks before process exit. Fortunately, the values are typically not very large, meaning you'd have to go through an awful lot of SIGHUP configuration-reload cycles to make the leakage amount to anything. Still, for a long-lived postmaster process it could potentially be a problem. Oversight in commit 2594cf0e8. Back-patch to all supported branches. Discussion: https://postgr.es/m/16666-2c41a4eec61b03e1@postgresql.org
2020-09-14Message fixes and style improvementsPeter Eisentraut
2020-09-09Minor fixes in docs and error messages.Tom Lane
Alexander Lakhin Discussion: https://postgr.es/m/ce7debdd-c943-d7a7-9b41-687107b27831@gmail.com
2020-07-29Add hash_mem_multiplier GUC.Peter Geoghegan
Add a GUC that acts as a multiplier on work_mem. It gets applied when sizing executor node hash tables that were previously size constrained using work_mem alone. The new GUC can be used to preferentially give hash-based nodes more memory than the generic work_mem limit. It is intended to enable admin tuning of the executor's memory usage. Overall system throughput and system responsiveness can be improved by giving hash-based executor nodes more memory (especially over sort-based alternatives, which are often much less sensitive to being memory constrained). The default value for hash_mem_multiplier is 1.0, which is also the minimum valid value. This means that hash-based nodes continue to apply work_mem in the traditional way by default. hash_mem_multiplier is generally useful. However, it is being added now due to concerns about hash aggregate performance stability for users that upgrade to Postgres 13 (which added disk-based hash aggregation in commit 1f39bce0). While the old hash aggregate behavior risked out-of-memory errors, it is nevertheless likely that many users actually benefited. Hash agg's previous indifference to work_mem during query execution was not just faster; it also accidentally made aggregation resilient to grouping estimate problems (at least in cases where this didn't create destabilizing memory pressure). hash_mem_multiplier can provide a certain kind of continuity with the behavior of Postgres 12 hash aggregates in cases where the planner incorrectly estimates that all groups (plus related allocations) will fit in work_mem/hash_mem. This seems necessary because hash-based aggregation is usually much slower when only a small fraction of all groups can fit. Even when it isn't possible to totally avoid hash aggregates that spill, giving hash aggregation more memory will reliably improve performance (the same cannot be said for external sort operations, which appear to be almost unaffected by memory availability provided it's at least possible to get a single merge pass). The PostgreSQL 13 release notes should advise users that increasing hash_mem_multiplier can help with performance regressions associated with hash aggregation. That can be taken care of by a later commit. Author: Peter Geoghegan Reviewed-By: Álvaro Herrera, Jeff Davis Discussion: https://postgr.es/m/20200625203629.7m6yvut7eqblgmfo@alap3.anarazel.de Discussion: https://postgr.es/m/CAH2-WzmD%2Bi1pG6rc1%2BCjc4V6EaFJ_qSuKCCHVnH%3DoruqD-zqow%40mail.gmail.com Backpatch: 13-, where disk-based hash aggregation was introduced.
2020-07-27Remove hashagg_avoid_disk_plan GUC.Peter Geoghegan
Note: This GUC was originally named enable_hashagg_disk when it appeared in commit 1f39bce0, which added disk-based hash aggregation. It was subsequently renamed in commit 92c58fd9. Author: Peter Geoghegan Reviewed-By: Jeff Davis, Álvaro Herrera Discussion: https://postgr.es/m/9d9d1e1252a52ea1bad84ea40dbebfd54e672a0f.camel%40j-davis.com Backpatch: 13-, where disk-based hash aggregation was introduced.
2020-07-20Rename wal_keep_segments to wal_keep_size.Fujii Masao
max_slot_wal_keep_size that was added in v13 and wal_keep_segments are the GUC parameters to specify how much WAL files to retain for the standby servers. While max_slot_wal_keep_size accepts the number of bytes of WAL files, wal_keep_segments accepts the number of WAL files. This difference of setting units between those similar parameters could be confusing to users. To alleviate this situation, this commit renames wal_keep_segments to wal_keep_size, and make users specify the WAL size in it instead of the number of WAL files. There was also the idea to rename max_slot_wal_keep_size to max_slot_wal_keep_segments, in the discussion. But we have been moving away from measuring in segments, for example, checkpoint_segments was replaced by max_wal_size. So we concluded to rename wal_keep_segments to wal_keep_size. Back-patch to v13 where max_slot_wal_keep_size was added. Author: Fujii Masao Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, David Steele Discussion: https://postgr.es/m/574b4ea3-e0f9-b175-ead2-ebea7faea855@oss.nttdata.com
2020-07-05Rename enable_incrementalsort for clarityPeter Eisentraut
Author: James Coleman <jtc331@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/df652910-e985-9547-152c-9d4357dc3979%402ndquadrant.com
2020-06-11Rework HashAgg GUCs.Jeff Davis
Eliminate enable_groupingsets_hash_disk, which was primarily useful for testing grouping sets that use HashAgg and spill. Instead, hack the table stats to convince the planner to choose hashed aggregation for grouping sets that will spill to disk. Suggested by Melanie Plageman. Rename enable_hashagg_disk to hashagg_avoid_disk_plan, and invert the meaning of on/off. The new name indicates more strongly that it only affects the planner. Also, the word "avoid" is less definite, which should avoid surprises when HashAgg still needs to use the disk. Change suggested by Justin Pryzby, though I chose a different GUC name. Discussion: https://postgr.es/m/CAAKRu_aisiENMsPM2gC4oUY1hHG3yrCwY-fXUg22C6_MJUwQdA%40mail.gmail.com Discussion: https://postgr.es/m/20200610021544.GA14879@telsasoft.com Backpatch-through: 13
2020-06-10Update description of parameter password_encryptionPeter Eisentraut
The previous description string still described the pre-PostgreSQL 10 (pre eb61136dc75a76caef8460fa939244d8593100f2) behavior of selecting between encrypted and unencrypted, but it is now choosing between encryption algorithms.
2020-06-07Formatting and punctuation improvements in postgresql.conf.samplePeter Eisentraut
2020-05-28Fix some mentions to memory units in postgresql.conf.sampleMichael Paquier
The default unit for max_slot_wal_keep_size is megabytes. While on it, also change temp_file_limit to use a more consistent wording. Reported-by: Jeff Janes, Fujii Masao Author: Kyotaro Horiguchi Discussion: https://postgr.es/m/CAMkU=1wWZhhjpwRFKJ9waQGxxROeC0P6UqPvb90fAaGz7dhoHA@mail.gmail.com
2020-05-21Clear some style deviations.Noah Misch
2020-05-14Initial pgindent and pgperltidy run for v13.Tom Lane
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.
2020-05-13Dial back -Wimplicit-fallthrough to level 3Alvaro Herrera
The additional pain from level 4 is excessive for the gain. Also revert all the source annotation changes to their original wordings, to avoid back-patching pain. Discussion: https://postgr.es/m/31166.1589378554@sss.pgh.pa.us
2020-05-12Add -Wimplicit-fallthrough to CFLAGS and CXXFLAGSAlvaro Herrera
Use it at level 4, a bit more restrictive than the default level, and tweak our commanding comments to FALLTHROUGH. (However, leave zic.c alone, since it's external code; to avoid the warnings that would appear there, change CFLAGS for that file in the Makefile.) Author: Julien Rouhaud <rjuju123@gmail.com> Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/20200412081825.qyo5vwwco3fv4gdo@nol Discussion: https://postgr.es/m/flat/E1fDenm-0000C8-IJ@gemulon.postgresql.org
2020-04-07Allow users to limit storage reserved by replication slotsAlvaro Herrera
Replication slots are useful to retain data that may be needed by a replication system. But experience has shown that allowing them to retain excessive data can lead to the primary failing because of running out of space. This new feature allows the user to configure a maximum amount of space to be reserved using the new option max_slot_wal_keep_size. Slots that overrun that space are invalidated at checkpoint time, enabling the storage to be released. Author: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp> Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com> Reviewed-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com> Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/20170228.122736.123383594.horiguchi.kyotaro@lab.ntt.co.jp
2020-04-06Implement Incremental SortTomas Vondra
Incremental Sort is an optimized variant of multikey sort for cases when the input is already sorted by a prefix of the requested sort keys. For example when the relation is already sorted by (key1, key2) and we need to sort it by (key1, key2, key3) we can simply split the input rows into groups having equal values in (key1, key2), and only sort/compare the remaining column key3. This has a number of benefits: - Reduced memory consumption, because only a single group (determined by values in the sorted prefix) needs to be kept in memory. This may also eliminate the need to spill to disk. - Lower startup cost, because Incremental Sort produce results after each prefix group, which is beneficial for plans where startup cost matters (like for example queries with LIMIT clause). We consider both Sort and Incremental Sort, and decide based on costing. The implemented algorithm operates in two different modes: - Fetching a minimum number of tuples without check of equality on the prefix keys, and sorting on all columns when safe. - Fetching all tuples for a single prefix group and then sorting by comparing only the remaining (non-prefix) keys. We always start in the first mode, and employ a heuristic to switch into the second mode if we believe it's beneficial - the goal is to minimize the number of unnecessary comparions while keeping memory consumption below work_mem. This is a very old patch series. The idea was originally proposed by Alexander Korotkov back in 2013, and then revived in 2017. In 2018 the patch was taken over by James Coleman, who wrote and rewrote most of the current code. There were many reviewers/contributors since 2013 - I've done my best to pick the most active ones, and listed them in this commit message. Author: James Coleman, Alexander Korotkov Reviewed-by: Tomas Vondra, Andreas Karlsson, Marti Raudsepp, Peter Geoghegan, Robert Haas, Thomas Munro, Antonin Houska, Andres Freund, Alexander Kuzmenkov Discussion: https://postgr.es/m/CAPpHfdscOX5an71nHd8WSUH6GNOCf=V7wgDaTXdDd9=goN-gfA@mail.gmail.com Discussion: https://postgr.es/m/CAPpHfds1waRZ=NOmueYq0sx1ZSCnt+5QJvizT8ndT2=etZEeAQ@mail.gmail.com
2020-04-04Skip WAL for new relfilenodes, under wal_level=minimal.Noah Misch
Until now, only selected bulk operations (e.g. COPY) did this. If a given relfilenode received both a WAL-skipping COPY and a WAL-logged operation (e.g. INSERT), recovery could lose tuples from the COPY. See src/backend/access/transam/README section "Skipping WAL for New RelFileNode" for the new coding rules. Maintainers of table access methods should examine that section. To maintain data durability, just before commit, we choose between an fsync of the relfilenode and copying its contents to WAL. A new GUC, wal_skip_threshold, guides that choice. If this change slows a workload that creates small, permanent relfilenodes under wal_level=minimal, try adjusting wal_skip_threshold. Users setting a timeout on COMMIT may need to adjust that timeout, and log_min_duration_statement analysis will reflect time consumption moving to COMMIT from commands like COPY. Internally, this requires a reliable determination of whether RollbackAndReleaseCurrentSubTransaction() would unlink a relation's current relfilenode. Introduce rd_firstRelfilenodeSubid. Amend the specification of rd_createSubid such that the field is zero when a new rel has an old rd_node. Make relcache.c retain entries for certain dropped relations until end of transaction. Bump XLOG_PAGE_MAGIC, since this introduces XLOG_GIST_ASSIGN_LSN. Future servers accept older WAL, so this bump is discretionary. Kyotaro Horiguchi, reviewed (in earlier, similar versions) by Robert Haas. Heikki Linnakangas and Michael Paquier implemented earlier designs that materially clarified the problem. Reviewed, in earlier designs, by Andrew Dunstan, Andres Freund, Alvaro Herrera, Tom Lane, Fujii Masao, and Simon Riggs. Reported by Martijn van Oosterhout. Discussion: https://postgr.es/m/20150702220524.GA9392@svana.org
2020-04-02Improve user control over truncation of logged bind-parameter values.Tom Lane
This patch replaces the boolean GUC log_parameters_on_error introduced by commit ba79cb5dc with an integer log_parameter_max_length_on_error, adding the ability to specify how many bytes to trim each logged parameter value to. (The previous coding hard-wired that choice at 64 bytes.) In addition, add a new parameter log_parameter_max_length that provides similar control over truncation of query parameters that are logged in response to statement-logging options, as opposed to errors. Previous releases always logged such parameters in full, possibly causing log bloat. For backwards compatibility with prior releases, log_parameter_max_length defaults to -1 (log in full), while log_parameter_max_length_on_error defaults to 0 (no logging). Per discussion, log_parameter_max_length is SUSET since the DBA should control routine logging behavior, but log_parameter_max_length_on_error is USERSET because it also affects errcontext data sent back to the client. Alexey Bashtanov, editorialized a little by me Discussion: https://postgr.es/m/b10493cc-a399-a03a-67c7-068f2791ee50@imap.cc
2020-04-02Add maintenance_io_concurrency to postgresql.conf.sample.Thomas Munro
New GUC from commit fc34b0d9.
2020-03-28Trigger autovacuum based on number of INSERTsDavid Rowley
Traditionally autovacuum has only ever invoked a worker based on the estimated number of dead tuples in a table and for anti-wraparound purposes. For the latter, with certain classes of tables such as insert-only tables, anti-wraparound vacuums could be the first vacuum that the table ever receives. This could often lead to autovacuum workers being busy for extended periods of time due to having to potentially freeze every page in the table. This could be particularly bad for very large tables. New clusters, or recently pg_restored clusters could suffer even more as many large tables may have the same relfrozenxid, which could result in large numbers of tables requiring an anti-wraparound vacuum all at once. Here we aim to reduce the work required by anti-wraparound and aggressive vacuums in general, by triggering autovacuum when the table has received enough INSERTs. This is controlled by adding two new GUCs and reloptions; autovacuum_vacuum_insert_threshold and autovacuum_vacuum_insert_scale_factor. These work exactly the same as the existing scale factor and threshold controls, only base themselves off the number of inserts since the last vacuum, rather than the number of dead tuples. New controls were added rather than reusing the existing controls, to allow these new vacuums to be tuned independently and perhaps even completely disabled altogether, which can be done by setting autovacuum_vacuum_insert_threshold to -1. We make no attempt to skip index cleanup operations on these vacuums as they may trigger for an insert-mostly table which continually doesn't have enough dead tuples to trigger an autovacuum for the purpose of removing those dead tuples. If we were to skip cleaning the indexes in this case, then it is possible for the index(es) to become bloated over time. There are additional benefits to triggering autovacuums based on inserts, as tables which never contain enough dead tuples to trigger an autovacuum are now more likely to receive a vacuum, which can mark more of the table as "allvisible" and encourage the query planner to make use of Index Only Scans. Currently, we still obey vacuum_freeze_min_age when triggering these new autovacuums based on INSERTs. For large insert-only tables, it may be beneficial to lower the table's autovacuum_freeze_min_age so that tuples are eligible to be frozen sooner. Here we've opted not to zero that for these types of vacuums, since the table may just be insert-mostly and we may otherwise freeze tuples that are still destined to be updated or removed in the near future. There was some debate to what exactly the new scale factor and threshold should default to. For now, these are set to 0.2 and 1000, respectively. There may be some motivation to adjust these before the release. Author: Laurenz Albe, Darafei Praliaskouski Reviewed-by: Alvaro Herrera, Masahiko Sawada, Chris Travers, Andres Freund, Justin Pryzby Discussion: https://postgr.es/m/CAC8Q8t%2Bj36G_bLF%3D%2B0iMo6jGNWnLnWb1tujXuJr-%2Bx8ZCCTqoQ%40mail.gmail.com
2020-03-27Allow walreceiver configuration to change on reloadAlvaro Herrera
The parameters primary_conninfo, primary_slot_name and wal_receiver_create_temp_slot can now be changed with a simple "reload" signal, no longer requiring a server restart. This is achieved by signalling the walreceiver process to terminate and having it start again with the new values. Thanks to Andres Freund, Kyotaro Horiguchi, Fujii Masao for discussion. Author: Sergei Kornilov <sk@zsrv.org> Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/19513901543181143@sas1-19a94364928d.qloud-c.yandex.net
2020-03-27Set wal_receiver_create_temp_slot PGC_POSTMASTERAlvaro Herrera
Commit 329730827848 gave walreceiver the ability to create and use a temporary replication slot, and made it controllable by a GUC (enabled by default) that can be changed with SIGHUP. That's useful but has two problems: one, it's possible to cause the origin server to fill its disk if the slot doesn't advance in time; and also there's a disconnect between state passed down via the startup process and GUCs that walreceiver reads directly. We handle the first problem by setting the option to disabled by default. If the user enables it, its on their head to make sure that disk doesn't fill up. We handle the second problem by passing the flag via startup rather than having walreceiver acquire it directly, and making it PGC_POSTMASTER (which ensures a walreceiver always has the fresh value). A future commit can relax this (to PGC_SIGHUP again) by having the startup process signal walreceiver to shutdown whenever the value changes. Author: Sergei Kornilov <sk@zsrv.org> Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://postgr.es/m/20200122055510.GH174860@paquier.xyz
2020-03-24Fix compiler warning on CygwinPeter Eisentraut
bf68b79e50e3359accc85c94fa23cc03abb9350a introduced an unused variable compiler warning on Cygwin.