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2025-03-26Use PG_MODULE_MAGIC_EXT in our installable shared libraries.Tom Lane
It seems potentially useful to label our shared libraries with version information, now that a facility exists for retrieving that. This patch labels them with the PG_VERSION string. There was some discussion about using semantic versioning conventions, but that doesn't seem terribly helpful for modules with no SQL-level presence; and for those that do have SQL objects, we typically expect them to support multiple revisions of the SQL definitions, so it'd still not be very helpful. I did not label any of src/test/modules/. It seems unnecessary since we don't install those, and besides there ought to be someplace that still provides test coverage for the original PG_MODULE_MAGIC macro. Author: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/dd4d1b59-d0fe-49d5-b28f-1e463b68fa32@gmail.com
2025-01-01Update copyright for 2025Bruce Momjian
Backpatch-through: 13
2024-10-28Remove unused #include's from contrib, pl, test .c filesPeter Eisentraut
as determined by IWYU Similar to commit dbbca2cf299, but for contrib, pl, and src/test/. Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/flat/0df1d5b1-8ca8-4f84-93be-121081bde049%40eisentraut.org
2024-09-12Reintroduce support for sequences in pgstattuple and pageinspect.Nathan Bossart
Commit 4b82664156 restricted a number of functions provided by contrib modules to only relations that use the "heap" table access method. Sequences always use this table access method, but they do not advertise as such in the pg_class system catalog, so the aforementioned commit also (presumably unintentionally) removed support for sequences from some of these functions. This commit reintroduces said support for sequences to these functions and adds a couple of relevant tests. Co-authored-by: Ayush Vatsa Reviewed-by: Robert Haas, Michael Paquier, Matthias van de Meent Discussion: https://postgr.es/m/CACX%2BKaP3i%2Bi9tdPLjF5JCHVv93xobEdcd_eB%2B638VDvZ3i%3DcQA%40mail.gmail.com Backpatch-through: 12
2024-09-09Consistently use PageGetExactFreeSpace() in pgstattuple.Tom Lane
Previously this code used PageGetHeapFreeSpace on heap pages, and usually used PageGetFreeSpace on index pages (though for some reason GetHashPageStats used PageGetExactFreeSpace instead). The difference is that those functions subtract off the size of a line pointer, and PageGetHeapFreeSpace has some additional rules about returning zero if adding another line pointer would require exceeding MaxHeapTuplesPerPage. Those things make sense when testing to see if a new tuple can be put on the page, but they seem pretty strange for pure statistics collection. Additionally, statapprox_heap had a special rule about counting a "new" page as being fully available space. This also seems strange, because it's not actually usable until VACUUM or some such process initializes the page. Moreover, it's inconsistent with what pgstat_heap does, which is to count such a page as having zero free space. So make it work like pgstat_heap, which as of this patch unconditionally calls PageGetExactFreeSpace. This is more of a definitional change than a bug fix, so no back-patch. The module's documentation doesn't define exactly what "free space" means either, so we left that as-is. Frédéric Yhuel, reviewed by Rafia Sabih and Andreas Karlsson. Discussion: https://postgr.es/m/3a18f843-76f6-4a84-8cca-49537fefa15d@dalibo.com
2024-01-04Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
2023-12-19pgstattuple: Fix failure with pgstathashindex() for partitioned indexesMichael Paquier
As coded, the function relied on index_open() when opening an index relation, allowing partitioned indexes to be processed by pgstathashindex(). This was leading to a "could not open file" error because partitioned indexes have no physical files, or to a crash with an assertion failure (like on HEAD). This issue is fixed by applying the same checks as the other stat functions for indexes, with a lookup at both RELKIND_INDEX and the index AM expected. Author: Alexander Lakhin Discussion: https://postgr.es/m/18246-f4d9ff7cb3af77e6@postgresql.org Backpatch-through: 12
2023-10-30Diagnose !indisvalid in more SQL functions.Noah Misch
pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen" class XX. The other functions succeeded on an empty index; they might have malfunctioned if the failed index build left torn I/O or other complex state. Report an ERROR in statistics functions pgstatindex, pgstatginindex, pgstathashindex, and pgstattuple. Report DEBUG1 and skip all index I/O in maintenance functions brin_desummarize_range, brin_summarize_new_values, brin_summarize_range, and gin_clean_pending_list. Back-patch to v11 (all supported versions). Discussion: https://postgr.es/m/20231001195309.a3@google.com
2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-12-20Add copyright notices to meson filesAndrew Dunstan
Discussion: https://postgr.es/m/222b43a5-2fb3-2c1b-9cd0-375d376c8246@dunslane.net
2022-10-07meson: Add support for building with precompiled headersAndres Freund
This substantially speeds up building for windows, due to the vast amount of headers included via windows.h. A cross build from linux targetting mingw goes from 994.11user 136.43system 0:31.58elapsed 3579%CPU to 422.41user 89.05system 0:14.35elapsed 3562%CPU The wins on windows are similar-ish (but I don't have a system at hand just now for actual numbers). Targetting other operating systems the wins are far smaller (tested linux, macOS, FreeBSD). For now precompiled headers are disabled by default, it's not clear how well they work on all platforms. E.g. on FreeBSD gcc doesn't seem to have working support, but clang does. When doing a full build precompiled headers are only beneficial for targets with multiple .c files, as meson builds a separate precompiled header for each target (so that different compilation options take effect). This commit therefore only changes target with at least two .c files to use precompiled headers. Because this commit adds b_pch=false to the default_options new build directories will have precompiled headers disabled by default, however existing build directories will continue use the default value of b_pch, which is true. Note that using precompiled headers with ccache requires setting CCACHE_SLOPPINESS=pch_defines,time_macros to get hits. Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Discussion: https://postgr.es/m/CA+hUKG+50eOUbN++ocDc0Qnp9Pvmou23DSXu=ZA6fepOcftKqA@mail.gmail.com Discussion: https://postgr.es/m/c5736f70-bb6d-8d25-e35c-e3d886e4e905@enterprisedb.com Discussion: https://postgr.es/m/20190826054000.GE7005%40paquier.xyz
2022-10-05meson: Add windows resource filesAndres Freund
The generated resource files aren't exactly the same ones as the old buildsystems generate. Previously "InternalName" and "OriginalFileName" were mostly wrong / not set (despite being required), but that was hard to fix in at least the make build. Additionally, the meson build falls back to a "auto-generated" description when not set, and doesn't set it in a few cases - unlikely that anybody looks at these descriptions in detail. Author: Andres Freund <andres@anarazel.de> Author: Nazir Bilal Yavuz <byavuz81@gmail.com> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
2022-09-22meson: Add initial version of meson based build systemAndres Freund
Autoconf is showing its age, fewer and fewer contributors know how to wrangle it. Recursive make has a lot of hard to resolve dependency issues and slow incremental rebuilds. Our home-grown MSVC build system is hard to maintain for developers not using Windows and runs tests serially. While these and other issues could individually be addressed with incremental improvements, together they seem best addressed by moving to a more modern build system. After evaluating different build system choices, we chose to use meson, to a good degree based on the adoption by other open source projects. We decided that it's more realistic to commit a relatively early version of the new build system and mature it in tree. This commit adds an initial version of a meson based build system. It supports building postgres on at least AIX, FreeBSD, Linux, macOS, NetBSD, OpenBSD, Solaris and Windows (however only gcc is supported on aix, solaris). For Windows/MSVC postgres can now be built with ninja (faster, particularly for incremental builds) and msbuild (supporting the visual studio GUI, but building slower). Several aspects (e.g. Windows rc file generation, PGXS compatibility, LLVM bitcode generation, documentation adjustments) are done in subsequent commits requiring further review. Other aspects (e.g. not installing test-only extensions) are not yet addressed. When building on Windows with msbuild, builds are slower when using a visual studio version older than 2019, because those versions do not support MultiToolTask, required by meson for intra-target parallelism. The plan is to remove the MSVC specific build system in src/tools/msvc soon after reaching feature parity. However, we're not planning to remove the autoconf/make build system in the near future. Likely we're going to keep at least the parts required for PGXS to keep working around until all supported versions build with meson. Some initial help for postgres developers is at https://wiki.postgresql.org/wiki/Meson With contributions from Thomas Munro, John Naylor, Stone Tickle and others. Author: Andres Freund <andres@anarazel.de> Author: Nazir Bilal Yavuz <byavuz81@gmail.com> Author: Peter Eisentraut <peter@eisentraut.org> Reviewed-By: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Discussion: https://postgr.es/m/20211012083721.hvixq4pnh2pixr3j@alap3.anarazel.de
2022-09-12pgstattuple: Use double consistently for percentagesPeter Eisentraut
pgstattuple uses data type double for other percentage calculations and exposes those values to the users via the float8 data type. However, scanned_percent in struct output_type is of type uint64, even though it is later returned via Float8GetDatum(). Change it to use double to be inline with other percentages. Author: Bharath Rupireddy Reviewed-by: Peter Eisentraut Discussion: https://www.postgresql.org/message-id/36ee692b-232f-0484-ce94-dc39d82021ad%40enterprisedb.com
2022-07-16Replace many MemSet calls with struct initializationPeter Eisentraut
This replaces all MemSet() calls with struct initialization where that is easily and obviously possible. (For example, some cases have to worry about padding bits, so I left those.) (The same could be done with appropriate memset() calls, but this patch is part of an effort to phase out MemSet(), so it doesn't touch memset() calls.) Reviewed-by: Ranier Vilela <ranier.vf@gmail.com> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/9847b13c-b785-f4e2-75c3-12ec77a3b05c@enterprisedb.com
2022-05-12Pre-beta mechanical code beautification.Tom Lane
Run pgindent, pgperltidy, and reformat-dat-files. I manually fixed a couple of comments that pgindent uglified.
2022-04-01Add macros in hash and btree AMs to get the special area of their pagesMichael Paquier
This makes the code more consistent with SpGiST, GiST and GIN, that already use this style, and the idea is to make easier the introduction of more sanity checks for each of these AM-specific macros. BRIN uses a different set of macros to get a page's type and flags, so it has no need for something similar. Author: Matthias van de Meent Discussion: https://postgr.es/m/CAEze2WjE3+tGO9Fs9+iZMU+z6mMZKo54W1Zt98WKqbEUHbHOBg@mail.gmail.com
2022-01-08Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-12-03Some RELKIND macro refactoringPeter Eisentraut
Add more macros to group some RELKIND_* macros: - RELKIND_HAS_PARTITIONS() - RELKIND_HAS_TABLESPACE() - RELKIND_HAS_TABLE_AM() Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/flat/a574c8f1-9c84-93ad-a9e5-65233d6fc00f%40enterprisedb.com
2021-07-08Improve error messages about mismatching relkindPeter Eisentraut
Most error messages about a relkind that was not supported or appropriate for the command was of the pattern "relation \"%s\" is not a table, foreign table, or materialized view" This style can become verbose and tedious to maintain. Moreover, it's not very helpful: If I'm trying to create a comment on a TOAST table, which is not supported, then the information that I could have created a comment on a materialized view is pointless. Instead, write the primary error message shorter and saying more directly that what was attempted is not possible. Then, in the detail message, explain that the operation is not supported for the relkind the object was. To simplify that, add a new function errdetail_relkind_not_supported() that does this. In passing, make use of RELKIND_HAS_STORAGE() where appropriate, instead of listing out the relkinds individually. Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Discussion: https://www.postgresql.org/message-id/flat/dc35a398-37d0-75ce-07ea-1dd71d98f8ec@2ndquadrant.com
2021-02-25Use full 64-bit XIDs in deleted nbtree pages.Peter Geoghegan
Otherwise we risk "leaking" deleted pages by making them non-recyclable indefinitely. Commit 6655a729 did the same thing for deleted pages in GiST indexes. That work was used as a starting point here. Stop storing an XID indicating the oldest bpto.xact across all deleted though unrecycled pages in nbtree metapages. There is no longer any reason to care about that condition/the oldest XID. It only ever made sense when wraparound was something _bt_vacuum_needs_cleanup() had to consider. The btm_oldest_btpo_xact metapage field has been repurposed and renamed. It is now btm_last_cleanup_num_delpages, which is used to remember how many non-recycled deleted pages remain from the last VACUUM (in practice its value is usually the precise number of pages that were _newly deleted_ during the specific VACUUM operation that last set the field). The general idea behind storing btm_last_cleanup_num_delpages is to use it to give _some_ consideration to non-recycled deleted pages inside _bt_vacuum_needs_cleanup() -- though never too much. We only really need to avoid leaving a truly excessive number of deleted pages in an unrecycled state forever. We only do this to cover certain narrow cases where no other factor makes VACUUM do a full scan, and yet the index continues to grow (and so actually misses out on recycling existing deleted pages). These metapage changes result in a clear user-visible benefit: We no longer trigger full index scans during VACUUM operations solely due to the presence of only 1 or 2 known deleted (though unrecycled) blocks from a very large index. All that matters now is keeping the costs and benefits in balance over time. Fix an issue that has been around since commit 857f9c36, which added the "skip full scan of index" mechanism (i.e. the _bt_vacuum_needs_cleanup() logic). The accuracy of btm_last_cleanup_num_heap_tuples accidentally hinged upon _when_ the source value gets stored. We now always store btm_last_cleanup_num_heap_tuples in btvacuumcleanup(). This fixes the issue because IndexVacuumInfo.num_heap_tuples (the source field) is expected to accurately indicate the state of the table _after_ the VACUUM completes inside btvacuumcleanup(). A backpatchable fix cannot easily be extracted from this commit. A targeted fix for the issue will follow in a later commit, though that won't happen today. I (pgeoghegan) have chosen to remove any mention of deleted pages in the documentation of the vacuum_cleanup_index_scale_factor GUC/param, since the presence of deleted (though unrecycled) pages is no longer of much concern to users. The vacuum_cleanup_index_scale_factor description in the docs now seems rather unclear in any case, and it should probably be rewritten in the near future. Perhaps some passing mention of page deletion will be added back at the same time. Bump XLOG_PAGE_MAGIC due to nbtree WAL records using full XIDs now. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com> Discussion: https://postgr.es/m/CAH2-WznpdHvujGUwYZ8sihX=d5u-tRYhi-F4wnV2uN2zHpMUXw@mail.gmail.com
2021-02-08Correct pgstattuple B-Tree page comments.Peter Geoghegan
2021-01-02Update copyright for 2021Bruce Momjian
Backpatch-through: 9.5
2020-08-30Redefine pg_class.reltuples to be -1 before the first VACUUM or ANALYZE.Tom Lane
Historically, we've considered the state with relpages and reltuples both zero as indicating that we do not know the table's tuple density. This is problematic because it's impossible to distinguish "never yet vacuumed" from "vacuumed and seen to be empty". In particular, a user cannot use VACUUM or ANALYZE to override the planner's normal heuristic that an empty table should not be believed to be empty because it is probably about to get populated. That heuristic is a good safety measure, so I don't care to abandon it, but there should be a way to override it if the table is indeed intended to stay empty. Hence, represent the initial state of ignorance by setting reltuples to -1 (relpages is still set to zero), and apply the minimum-ten-pages heuristic only when reltuples is still -1. If the table is empty, VACUUM or ANALYZE (but not CREATE INDEX) will override that to reltuples = relpages = 0, and then we'll plan on that basis. This requires a bunch of fiddly little changes, but we can get rid of some ugly kluges that were formerly needed to maintain the old definition. One notable point is that FDWs' GetForeignRelSize methods will see baserel->tuples = -1 when no ANALYZE has been done on the foreign table. That seems like a net improvement, since those methods were formerly also in the dark about what baserel->tuples = 0 really meant. Still, it is an API change. I bumped catversion because code predating this change would get confused by seeing reltuples = -1. Discussion: https://postgr.es/m/F02298E0-6EF4-49A1-BCB6-C484794D9ACC@thebuild.com
2020-08-12snapshot scalability: Don't compute global horizons while building snapshots.Andres Freund
To make GetSnapshotData() more scalable, it cannot not look at at each proc's xmin: While snapshot contents do not need to change whenever a read-only transaction commits or a snapshot is released, a proc's xmin is modified in those cases. The frequency of xmin modifications leads to, particularly on higher core count systems, many cache misses inside GetSnapshotData(), despite the data underlying a snapshot not changing. That is the most significant source of GetSnapshotData() scaling poorly on larger systems. Without accessing xmins, GetSnapshotData() cannot calculate accurate horizons / thresholds as it has so far. But we don't really have to: The horizons don't actually change that much between GetSnapshotData() calls. Nor are the horizons actually used every time a snapshot is built. The trick this commit introduces is to delay computation of accurate horizons until there use and using horizon boundaries to determine whether accurate horizons need to be computed. The use of RecentGlobal[Data]Xmin to decide whether a row version could be removed has been replaces with new GlobalVisTest* functions. These use two thresholds to determine whether a row can be pruned: 1) definitely_needed, indicating that rows deleted by XIDs >= definitely_needed are definitely still visible. 2) maybe_needed, indicating that rows deleted by XIDs < maybe_needed can definitely be removed GetSnapshotData() updates definitely_needed to be the xmin of the computed snapshot. When testing whether a row can be removed (with GlobalVisTestIsRemovableXid()) and the tested XID falls in between the two (i.e. XID >= maybe_needed && XID < definitely_needed) the boundaries can be recomputed to be more accurate. As it is not cheap to compute accurate boundaries, we limit the number of times that happens in short succession. As the boundaries used by GlobalVisTestIsRemovableXid() are never reset (with maybe_needed updated by GetSnapshotData()), it is likely that further test can benefit from an earlier computation of accurate horizons. To avoid regressing performance when old_snapshot_threshold is set (as that requires an accurate horizon to be computed), heap_page_prune_opt() doesn't unconditionally call TransactionIdLimitedForOldSnapshots() anymore. Both the computation of the limited horizon, and the triggering of errors (with SetOldSnapshotThresholdTimestamp()) is now only done when necessary to remove tuples. This commit just removes the accesses to PGXACT->xmin from GetSnapshotData(), but other members of PGXACT residing in the same cache line are accessed. Therefore this in itself does not result in a significant improvement. Subsequent commits will take advantage of the fact that GetSnapshotData() now does not need to access xmins anymore. Note: This contains a workaround in heap_page_prune_opt() to keep the snapshot_too_old tests working. While that workaround is ugly, the tests currently are not meaningful, and it seems best to address them separately. Author: Andres Freund <andres@anarazel.de> Reviewed-By: Robert Haas <robertmhaas@gmail.com> Reviewed-By: Thomas Munro <thomas.munro@gmail.com> Reviewed-By: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/20200301083601.ews6hz5dduc3w2se@alap3.anarazel.de
2020-06-29pgstattuple: Have pgstattuple_approx accept TOAST tablesPeter Eisentraut
TOAST tables have a visibility map and a free space map, so they can be supported by pgstattuple_approx just fine. Add test cases to show how various pgstattuple functions accept TOAST tables. Also add similar tests to pg_visibility, which already accepted TOAST tables correctly but had no test coverage for them. Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at> Discussion: https://www.postgresql.org/message-id/flat/27c4496a-02b9-dc87-8f6f-bddbef54e0fe@2ndquadrant.com
2020-02-19Remove support for upgrading extensions from "unpackaged" state.Tom Lane
Andres Freund pointed out that allowing non-superusers to run "CREATE EXTENSION ... FROM unpackaged" has security risks, since the unpackaged-to-1.0 scripts don't try to verify that the existing objects they're modifying are what they expect. Just attaching such objects to an extension doesn't seem too dangerous, but some of them do more than that. We could have resolved this, perhaps, by still requiring superuser privilege to use the FROM option. However, it's fair to ask just what we're accomplishing by continuing to lug the unpackaged-to-1.0 scripts forward. None of them have received any real testing since 9.1 days, so they may not even work anymore (even assuming that one could still load the previous "loose" object definitions into a v13 database). And an installation that's trying to go from pre-9.1 to v13 or later in one jump is going to have worse compatibility problems than whether there's a trivial way to convert their contrib modules into extension style. Hence, let's just drop both those scripts and the core-code support for "CREATE EXTENSION ... FROM". Discussion: https://postgr.es/m/20200213233015.r6rnubcvl4egdh5r@alap3.anarazel.de
2020-01-30Remove excess parens in ereport() callsAlvaro Herrera
Cosmetic cleanup, not worth backpatching. Discussion: https://postgr.es/m/20200129200401.GA6303@alvherre.pgsql Reviewed-by: Tom Lane, Michael Paquier
2020-01-01Update copyrights for 2020Bruce Momjian
Backpatch-through: update all files in master, backpatch legal files through 9.4
2019-11-05Split all OBJS style lines in makefiles into one-line-per-entry style.Andres Freund
When maintaining or merging patches, one of the most common sources for conflicts are the list of objects in makefiles. Especially when the split across lines has been changed on both sides, which is somewhat common due to attempting to stay below 80 columns, those conflicts are unnecessarily laborious to resolve. By splitting, and alphabetically sorting, OBJS style lines into one object per line, conflicts should be less frequent, and easier to resolve when they still occur. Author: Andres Freund Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
2019-10-24Make the order of the header file includes consistent in contrib modules.Amit Kapila
The basic rule we follow here is to always first include 'postgres.h' or 'postgres_fe.h' whichever is applicable, then system header includes and then Postgres header includes.  In this, we also follow that all the Postgres header includes are in order based on their ASCII value.  We generally follow these rules, but the code has deviated in many places. This commit makes it consistent just for contrib modules. The later commits will enforce similar rules in other parts of code. Author: Vignesh C Reviewed-by: Amit Kapila Discussion: https://postgr.es/m/CALDaNm2Sznv8RR6Ex-iJO6xAdsxgWhCoETkaYX=+9DW3q0QCfA@mail.gmail.com
2019-07-16Fix inconsistencies and typos in the treeMichael Paquier
This is numbered take 7, and addresses a set of issues around: - Fixes for typos and incorrect reference names. - Removal of unneeded comments. - Removal of unreferenced functions and structures. - Fixes regarding variable name consistency. Author: Alexander Lakhin Discussion: https://postgr.es/m/10bfd4ac-3e7c-40ab-2b2e-355ed15495e8@gmail.com
2019-05-22Phase 2 pgindent run for v12.Tom Lane
Switch to 2.1 version of pg_bsd_indent. This formats multiline function declarations "correctly", that is with additional lines of parameter declarations indented to match where the first line's left parenthesis is. Discussion: https://postgr.es/m/CAEepm=0P3FeTXRcU5B2W3jv3PgRVZ-kGUXLGfd42FFhUROO3ug@mail.gmail.com
2019-05-22Initial pgindent run for v12.Tom Lane
This is still using the 2.0 version of pg_bsd_indent. I thought it would be good to commit this separately, so as to document the differences between 2.0 and 2.1 behavior. Discussion: https://postgr.es/m/16296.1558103386@sss.pgh.pa.us
2019-05-07Revert "Avoid the creation of the free space map for small heap relations".Amit Kapila
This feature was using a process local map to track the first few blocks in the relation. The map was reset each time we get the block with enough freespace. It was discussed that it would be better to track this map on a per-relation basis in relcache and then invalidate the same whenever vacuum frees up some space in the page or when FSM is created. The new design would be better both in terms of API design and performance. List of commits reverted, in reverse chronological order: 06c8a5090e Improve code comments in b0eaa4c51b. 13e8643bfc During pg_upgrade, conditionally skip transfer of FSMs. 6f918159a9 Add more tests for FSM. 9c32e4c350 Clear the local map when not used. 29d108cdec Update the documentation for FSM behavior.. 08ecdfe7e5 Make FSM test portable. b0eaa4c51b Avoid creation of the free space map for small heap relations. Discussion: https://postgr.es/m/20190416180452.3pm6uegx54iitbt5@alap3.anarazel.de
2019-04-01Only allow heap in a number of contrib modules.Andres Freund
Contrib modules pgrowlocks, pgstattuple and some functionality in pageinspect currently only supports the heap table AM. As they are all concerned with low-level details that aren't reasonably exposed via tableam, error out if invoked on a non heap relation. Author: Andres Freund Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
2019-03-20Make heap TID a tiebreaker nbtree index column.Peter Geoghegan
Make nbtree treat all index tuples as having a heap TID attribute. Index searches can distinguish duplicates by heap TID, since heap TID is always guaranteed to be unique. This general approach has numerous benefits for performance, and is prerequisite to teaching VACUUM to perform "retail index tuple deletion". Naively adding a new attribute to every pivot tuple has unacceptable overhead (it bloats internal pages), so suffix truncation of pivot tuples is added. This will usually truncate away the "extra" heap TID attribute from pivot tuples during a leaf page split, and may also truncate away additional user attributes. This can increase fan-out, especially in a multi-column index. Truncation can only occur at the attribute granularity, which isn't particularly effective, but works well enough for now. A future patch may add support for truncating "within" text attributes by generating truncated key values using new opclass infrastructure. Only new indexes (BTREE_VERSION 4 indexes) will have insertions that treat heap TID as a tiebreaker attribute, or will have pivot tuples undergo suffix truncation during a leaf page split (on-disk compatibility with versions 2 and 3 is preserved). Upgrades to version 4 cannot be performed on-the-fly, unlike upgrades from version 2 to version 3. contrib/amcheck continues to work with version 2 and 3 indexes, while also enforcing stricter invariants when verifying version 4 indexes. These stricter invariants are the same invariants described by "3.1.12 Sequencing" from the Lehman and Yao paper. A later patch will enhance the logic used by nbtree to pick a split point. This patch is likely to negatively impact performance without smarter choices around the precise point to split leaf pages at. Making these two mostly-distinct sets of enhancements into distinct commits seems like it might clarify their design, even though neither commit is particularly useful on its own. The maximum allowed size of new tuples is reduced by an amount equal to the space required to store an extra MAXALIGN()'d TID in a new high key during leaf page splits. The user-facing definition of the "1/3 of a page" restriction is already imprecise, and so does not need to be revised. However, there should be a compatibility note in the v12 release notes. Author: Peter Geoghegan Reviewed-By: Heikki Linnakangas, Alexander Korotkov Discussion: https://postgr.es/m/CAH2-WzkVb0Kom=R+88fDFb=JSxZMFvbHVC6Mn9LJ2n=X=kS-Uw@mail.gmail.com
2019-03-11tableam: Add and use scan APIs.Andres Freund
Too allow table accesses to be not directly dependent on heap, several new abstractions are needed. Specifically: 1) Heap scans need to be generalized into table scans. Do this by introducing TableScanDesc, which will be the "base class" for individual AMs. This contains the AM independent fields from HeapScanDesc. The previous heap_{beginscan,rescan,endscan} et al. have been replaced with a table_ version. There's no direct replacement for heap_getnext(), as that returned a HeapTuple, which is undesirable for a other AMs. Instead there's table_scan_getnextslot(). But note that heap_getnext() lives on, it's still used widely to access catalog tables. This is achieved by new scan_begin, scan_end, scan_rescan, scan_getnextslot callbacks. 2) The portion of parallel scans that's shared between backends need to be able to do so without the user doing per-AM work. To achieve that new parallelscan_{estimate, initialize, reinitialize} callbacks are introduced, which operate on a new ParallelTableScanDesc, which again can be subclassed by AMs. As it is likely that several AMs are going to be block oriented, block oriented callbacks that can be shared between such AMs are provided and used by heap. table_block_parallelscan_{estimate, intiialize, reinitialize} as callbacks, and table_block_parallelscan_{nextpage, init} for use in AMs. These operate on a ParallelBlockTableScanDesc. 3) Index scans need to be able to access tables to return a tuple, and there needs to be state across individual accesses to the heap to store state like buffers. That's now handled by introducing a sort-of-scan IndexFetchTable, which again is intended to be subclassed by individual AMs (for heap IndexFetchHeap). The relevant callbacks for an AM are index_fetch_{end, begin, reset} to create the necessary state, and index_fetch_tuple to retrieve an indexed tuple. Note that index_fetch_tuple implementations need to be smarter than just blindly fetching the tuples for AMs that have optimizations similar to heap's HOT - the currently alive tuple in the update chain needs to be fetched if appropriate. Similar to table_scan_getnextslot(), it's undesirable to continue to return HeapTuples. Thus index_fetch_heap (might want to rename that later) now accepts a slot as an argument. Core code doesn't have a lot of call sites performing index scans without going through the systable_* API (in contrast to loads of heap_getnext calls and working directly with HeapTuples). Index scans now store the result of a search in IndexScanDesc->xs_heaptid, rather than xs_ctup->t_self. As the target is not generally a HeapTuple anymore that seems cleaner. To be able to sensible adapt code to use the above, two further callbacks have been introduced: a) slot_callbacks returns a TupleTableSlotOps* suitable for creating slots capable of holding a tuple of the AMs type. table_slot_callbacks() and table_slot_create() are based upon that, but have additional logic to deal with views, foreign tables, etc. While this change could have been done separately, nearly all the call sites that needed to be adapted for the rest of this commit also would have been needed to be adapted for table_slot_callbacks(), making separation not worthwhile. b) tuple_satisfies_snapshot checks whether the tuple in a slot is currently visible according to a snapshot. That's required as a few places now don't have a buffer + HeapTuple around, but a slot (which in heap's case internally has that information). Additionally a few infrastructure changes were needed: I) SysScanDesc, as used by systable_{beginscan, getnext} et al. now internally uses a slot to keep track of tuples. While systable_getnext() still returns HeapTuples, and will so for the foreseeable future, the index API (see 1) above) now only deals with slots. The remainder, and largest part, of this commit is then adjusting all scans in postgres to use the new APIs. Author: Andres Freund, Haribabu Kommi, Alvaro Herrera Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de https://postgr.es/m/20160812231527.GA690404@alvherre.pgsql
2019-02-20Doc: Update the documentation for FSM behavior for small tables.Amit Kapila
In commit b0eaa4c51b, we have avoided the creation of FSM for small tables. So the functions that use FSM to compute the free space can return zero for such tables. This was previously also possible for the cases where the vacuum has not been triggered to update FSM. This commit updates the comments in code and documentation to reflect this behavior. Author: John Naylor Reviewed-by: Amit Kapila Discussion: https://postgr.es/m/CACPNZCtba-3m1q3A8gxA_vxg=T7gQf7gMbpR4Ciy5LntY-j+0Q@mail.gmail.com
2019-01-22Move remaining code from tqual.[ch] to heapam.h / heapam_visibility.c.Andres Freund
Given these routines are heap specific, and that there will be more generic visibility support in via table AM, it makes sense to move the prototypes to heapam.h (routines like HeapTupleSatisfiesVacuum will not be exposed in a generic fashion, because they are too storage specific). Similarly, the code in tqual.c is specific to heap, so moving it into access/heap/ makes sense. Author: Andres Freund Discussion: https://postgr.es/m/20180703070645.wchpu5muyto5n647@alap3.anarazel.de
2019-01-21Replace heapam.h includes with {table, relation}.h where applicable.Andres Freund
A lot of files only included heapam.h for relation_open, heap_open etc - replace the heapam.h include in those files with the narrower header. Author: Andres Freund Discussion: https://postgr.es/m/20190111000539.xbv7s6w7ilcvm7dp@alap3.anarazel.de
2019-01-15Don't include heapam.h from others headers.Andres Freund
heapam.h previously was included in a number of widely used headers (e.g. execnodes.h, indirectly in executor.h, ...). That's problematic on its own, as heapam.h contains a lot of low-level details that don't need to be exposed that widely, but becomes more problematic with the upcoming introduction of pluggable table storage - it seems inappropriate for heapam.h to be included that widely afterwards. heapam.h was largely only included in other headers to get the HeapScanDesc typedef (which was defined in heapam.h, even though HeapScanDescData is defined in relscan.h). The better solution here seems to be to just use the underlying struct (forward declared where necessary). Similar for BulkInsertState. Another problem was that LockTupleMode was used in executor.h - parts of the file tried to cope without heapam.h, but due to the fact that it indirectly included it, several subsequent violations of that goal were not not noticed. We could just reuse the approach of declaring parameters as int, but it seems nicer to move LockTupleMode to lockoptions.h - that's not a perfect location, but also doesn't seem bad. As a number of files relied on implicitly included heapam.h, a significant number of files grew an explicit include. It's quite probably that a few external projects will need to do the same. Author: Andres Freund Reviewed-By: Alvaro Herrera Discussion: https://postgr.es/m/20190114000701.y4ttcb74jpskkcfb@alap3.anarazel.de
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-05-09pgstatindex, pageinspect: handle partitioned indexesAlvaro Herrera
Commit 8b08f7d4820f failed to update these modules to at least give non-broken error messages for partitioned indexes. Add appropriate error support to them. Peter G. was complaining about a problem of unfriendly error messages; while we haven't fixed that yet, subsequent discussion let to discovery of these unhandled cases. Author: Michaël Paquier Reported-by: Peter Geoghegan Discussion: https://postgr.es/m/CAH2-WzkOKptQiE51Bh4_xeEHhaBwHkZkGtKizrFMgEkfUuRRQg@mail.gmail.com
2018-05-09pgstatindex: HASH -> hashAlvaro Herrera
Fix the lone error message in the whole source tree to use capitalized HASH when referring to hash indexes, making it look like all the other messages. Someday it would be good to standardize 'B-Tree', 'B-tree', 'btree', and random other spellings, too, but that's a larger patch ... Author: Álvaro Herrera
2018-04-04Skip full index scan during cleanup of B-tree indexes when possibleTeodor Sigaev
Vacuum of index consists from two stages: multiple (zero of more) ambulkdelete calls and one amvacuumcleanup call. When workload on particular table is append-only, then autovacuum isn't intended to touch this table. However, user may run vacuum manually in order to fill visibility map and get benefits of index-only scans. Then ambulkdelete wouldn't be called for indexes of such table (because no heap tuples were deleted), only amvacuumcleanup would be called In this case, amvacuumcleanup would perform full index scan for two objectives: put recyclable pages into free space map and update index statistics. This patch allows btvacuumclanup to skip full index scan when two conditions are satisfied: no pages are going to be put into free space map and index statistics isn't stalled. In order to check first condition, we store oldest btpo_xact in the meta-page. When it's precedes RecentGlobalXmin, then there are some recyclable pages. In order to check second condition we store number of heap tuples observed during previous full index scan by cleanup. If fraction of newly inserted tuples is less than vacuum_cleanup_index_scale_factor, then statistics isn't considered to be stalled. vacuum_cleanup_index_scale_factor can be defined as both reloption and GUC (default). This patch bumps B-tree meta-page version. Upgrade of meta-page is performed "on the fly": during VACUUM meta-page is rewritten with new version. No special handling in pg_upgrade is required. Author: Masahiko Sawada, Alexander Korotkov Review by: Peter Geoghegan, Kyotaro Horiguchi, Alexander Korotkov, Yura Sokolov Discussion: https://www.postgresql.org/message-id/flat/CAD21AoAX+d2oD_nrd9O2YkpzHaFr=uQeGr9s1rKC3O4ENc568g@mail.gmail.com
2018-03-22Sync up our various ways of estimating pg_class.reltuples.Tom Lane
VACUUM thought that reltuples represents the total number of tuples in the relation, while ANALYZE counted only live tuples. This can cause "flapping" in the value when background vacuums and analyzes happen separately. The planner's use of reltuples essentially assumes that it's the count of live (visible) tuples, so let's standardize on having it mean live tuples. Another issue is that the definition of "live tuple" isn't totally clear; what should be done with INSERT_IN_PROGRESS or DELETE_IN_PROGRESS tuples? ANALYZE's choices in this regard are made on the assumption that if the originating transaction commits at all, it will happen after ANALYZE finishes, so we should ignore the effects of the in-progress transaction --- unless it is our own transaction, and then we should count it. Let's propagate this definition into VACUUM, too. Likewise propagate this definition into CREATE INDEX, and into contrib/pgstattuple's pgstattuple_approx() function. Tomas Vondra, reviewed by Haribabu Kommi, some corrections by me Discussion: https://postgr.es/m/16db4468-edfa-830a-f921-39a50498e77e@2ndquadrant.com
2018-03-15Fix more format truncation issuesPeter Eisentraut
Fix the warnings created by the compiler warning options -Wformat-overflow=2 -Wformat-truncation=2, supported since GCC 7. This is a more aggressive variant of the fixes in 6275f5d28a1577563f53f2171689d4f890a46881, which GCC 7 warned about by default. The issues are all harmless, but some dubious coding patterns are cleaned up. One issue that is of external interest is that BGW_MAXLEN is increased from 64 to 96. Apparently, the old value would cause the bgw_name of logical replication workers to be truncated in some circumstances. But this doesn't actually add those warning options. It appears that the warnings depend a bit on compilation and optimization options, so it would be annoying to have to keep up with that. This is more of a once-in-a-while cleanup. Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-13When updating reltuples after ANALYZE, just extrapolate from our sample.Tom Lane
The existing logic for updating pg_class.reltuples trusted the sampling results only for the pages ANALYZE actually visited, preferring to believe the previous tuple density estimate for all the unvisited pages. While there's some rationale for doing that for VACUUM (first that VACUUM is likely to visit a very nonrandom subset of pages, and second that we know for sure that the unvisited pages did not change), there's no such rationale for ANALYZE: by assumption, it's looked at an unbiased random sample of the table's pages. Furthermore, in a very large table ANALYZE will have examined only a tiny fraction of the table's pages, meaning it cannot slew the overall density estimate very far at all. In a table that is physically growing, this causes reltuples to increase nearly proportionally to the change in relpages, regardless of what is actually happening in the table. This has been observed to cause reltuples to become so much larger than reality that it effectively shuts off autovacuum, whose threshold for doing anything is a fraction of reltuples. (Getting to the point where that would happen seems to require some additional, not well understood, conditions. But it's undeniable that if reltuples is seriously off in a large table, ANALYZE alone will not fix it in any reasonable number of iterations, especially not if the table is continuing to grow.) Hence, restrict the use of vac_estimate_reltuples() to VACUUM alone, and in ANALYZE, just extrapolate from the sample pages on the assumption that they provide an accurate model of the whole table. If, by very bad luck, they don't, at least another ANALYZE will fix it; in the old logic a single bad estimate could cause problems indefinitely. In HEAD, let's remove vac_estimate_reltuples' is_analyze argument altogether; it was never used for anything and now it's totally pointless. But keep it in the back branches, in case any third-party code is calling this function. Per bug #15005. Back-patch to all supported branches. David Gould, reviewed by Alexander Kuzmenkov, cosmetic changes by me Discussion: https://postgr.es/m/20180117164916.3fdcf2e9@engels
2018-01-03Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3