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* Update copyright for 2019Bruce Momjian2019-01-02
| | | | Backpatch-through: certain files through 9.4
* Remove WITH OIDS support, change oid catalog column visibility.Andres Freund2018-11-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously tables declared WITH OIDS, including a significant fraction of the catalog tables, stored the oid column not as a normal column, but as part of the tuple header. This special column was not shown by default, which was somewhat odd, as it's often (consider e.g. pg_class.oid) one of the more important parts of a row. Neither pg_dump nor COPY included the contents of the oid column by default. The fact that the oid column was not an ordinary column necessitated a significant amount of special case code to support oid columns. That already was painful for the existing, but upcoming work aiming to make table storage pluggable, would have required expanding and duplicating that "specialness" significantly. WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0). Remove it. Removing includes: - CREATE TABLE and ALTER TABLE syntax for declaring the table to be WITH OIDS has been removed (WITH (oids[ = true]) will error out) - pg_dump does not support dumping tables declared WITH OIDS and will issue a warning when dumping one (and ignore the oid column). - restoring an pg_dump archive with pg_restore will warn when restoring a table with oid contents (and ignore the oid column) - COPY will refuse to load binary dump that includes oids. - pg_upgrade will error out when encountering tables declared WITH OIDS, they have to be altered to remove the oid column first. - Functionality to access the oid of the last inserted row (like plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed. The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false) for CREATE TABLE) is still supported. While that requires a bit of support code, it seems unnecessary to break applications / dumps that do not use oids, and are explicit about not using them. The biggest user of WITH OID columns was postgres' catalog. This commit changes all 'magic' oid columns to be columns that are normally declared and stored. To reduce unnecessary query breakage all the newly added columns are still named 'oid', even if a table's column naming scheme would indicate 'reloid' or such. This obviously requires adapting a lot code, mostly replacing oid access via HeapTupleGetOid() with access to the underlying Form_pg_*->oid column. The bootstrap process now assigns oids for all oid columns in genbki.pl that do not have an explicit value (starting at the largest oid previously used), only oids assigned later by oids will be above FirstBootstrapObjectId. As the oid column now is a normal column the special bootstrap syntax for oids has been removed. Oids are not automatically assigned during insertion anymore, all backend code explicitly assigns oids with GetNewOidWithIndex(). For the rare case that insertions into the catalog via SQL are called for the new pg_nextoid() function can be used (which only works on catalog tables). The fact that oid columns on system tables are now normal columns means that they will be included in the set of columns expanded by * (i.e. SELECT * FROM pg_class will now include the table's oid, previously it did not). It'd not technically be hard to hide oid column by default, but that'd mean confusing behavior would either have to be carried forward forever, or it'd cause breakage down the line. While it's not unlikely that further adjustments are needed, the scope/invasiveness of the patch makes it worthwhile to get merge this now. It's painful to maintain externally, too complicated to commit after the code code freeze, and a dependency of a number of other patches. Catversion bump, for obvious reasons. Author: Andres Freund, with contributions by John Naylor Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
* Update copyright for 2018Bruce Momjian2018-01-02
| | | | Backpatch-through: certain files through 9.3
* Phase 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Move isolationtester's is-blocked query into C code for speed.Tom Lane2017-04-10
| | | | | | | | | | | | | | | | | | | Commit 4deb41381 modified isolationtester's query to see whether a session is blocked to also check for waits occurring in GetSafeSnapshot. However, it did that in a way that enormously increased the query's runtime under CLOBBER_CACHE_ALWAYS, causing the buildfarm members that use that to run about four times slower than before, and in some cases fail entirely. To fix, push the entire logic into a dedicated backend function. This should actually reduce the CLOBBER_CACHE_ALWAYS runtime from what it was previously, though I've not checked that. In passing, expose a SQL function to check for safe-snapshot blockage, comparable to pg_blocking_pids. This is more or less free given the infrastructure built to solve the other problem, so we might as well. Thomas Munro Discussion: https://postgr.es/m/20170407165749.pstcakbc637opkax@alap3.anarazel.de
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Provide much better wait information in pg_stat_activity.Robert Haas2016-03-10
| | | | | | | | | | | | When a process is waiting for a heavyweight lock, we will now indicate the type of heavyweight lock for which it is waiting. Also, you can now see when a process is waiting for a lightweight lock - in which case we will indicate the individual lock name or the tranche, as appropriate - or for a buffer pin. Amit Kapila, Ildus Kurbangaliev, reviewed by me. Lots of helpful discussion and suggestions by many others, including Alexander Korotkov, Vladimir Borodin, and many others.
* Create a function to reliably identify which sessions block which others.Tom Lane2016-02-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces "pg_blocking_pids(int) returns int[]", which returns the PIDs of any sessions that are blocking the session with the given PID. Historically people have obtained such information using a self-join on the pg_locks view, but it's unreasonably tedious to do it that way with any modicum of correctness, and the addition of parallel queries has pretty much broken that approach altogether. (Given some more columns in the view than there are today, you could imagine handling parallel-query cases with a 4-way join; but ugh.) The new function has the following behaviors that are painful or impossible to get right via pg_locks: 1. Correctly understands which lock modes block which other ones. 2. In soft-block situations (two processes both waiting for conflicting lock modes), only the one that's in front in the wait queue is reported to block the other. 3. In parallel-query cases, reports all sessions blocking any member of the given PID's lock group, and reports a session by naming its leader process's PID, which will be the pg_backend_pid() value visible to clients. The motivation for doing this right now is mostly to fix the isolation tests. Commit 38f8bdcac4982215beb9f65a19debecaf22fd470 lobotomized isolationtester's is-it-waiting query by removing its ability to recognize nonconflicting lock modes, as a crude workaround for the inability to handle soft-block situations properly. But even without the lock mode tests, the old query was excessively slow, particularly in CLOBBER_CACHE_ALWAYS builds; some of our buildfarm animals fail the new deadlock-hard test because the deadlock timeout elapses before they can probe the waiting status of all eight sessions. Replacing the pg_locks self-join with use of pg_blocking_pids() is not only much more correct, but a lot faster: I measure it at about 9X faster in a typical dev build with Asserts, and 3X faster in CLOBBER_CACHE_ALWAYS builds. That should provide enough headroom for the slower CLOBBER_CACHE_ALWAYS animals to pass the test, without having to lengthen deadlock_timeout yet more and thus slow down the test for everyone else.
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* pgindent run for 9.5Bruce Momjian2015-05-23
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* Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.Andres Freund2015-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
* Create an infrastructure for parallel computation in PostgreSQL.Robert Haas2015-04-30
| | | | | | | | | | | | | | | | | This does four basic things. First, it provides convenience routines to coordinate the startup and shutdown of parallel workers. Second, it synchronizes various pieces of state (e.g. GUCs, combo CID mappings, transaction snapshot) from the parallel group leader to the worker processes. Third, it prohibits various operations that would result in unsafe changes to that state while parallelism is active. Finally, it propagates events that would result in an ErrorResponse, NoticeResponse, or NotifyResponse message being sent to the client from the parallel workers back to the master, from which they can then be sent on to the client. Robert Haas, Amit Kapila, Noah Misch, Rushabh Lathia, Jeevan Chalke. Suggestions and review from Andres Freund, Heikki Linnakangas, Noah Misch, Simon Riggs, Euler Taveira, and Jim Nasby.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Update copyright for 2014Bruce Momjian2014-01-07
| | | | | Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
* Update copyrights for 2013Bruce Momjian2013-01-01
| | | | | Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
* Split tuple struct defs from htup.h to htup_details.hAlvaro Herrera2012-08-30
| | | | | | | | | | | | This reduces unnecessary exposure of other headers through htup.h, which is very widely included by many files. I have chosen to move the function prototypes to the new file as well, because that means htup.h no longer needs to include tupdesc.h. In itself this doesn't have much effect in indirect inclusion of tupdesc.h throughout the tree, because it's also required by execnodes.h; but it's something to explore in the future, and it seemed best to do the htup.h change now while I'm busy with it.
* Run pgindent on 9.2 source tree in preparation for first 9.3Bruce Momjian2012-06-10
| | | | commit-fest.
* Update copyright notices for year 2012.Bruce Momjian2012-01-01
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* Remove unnecessary #include references, per pgrminclude script.Bruce Momjian2011-09-01
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* Create a "fast path" for acquiring weak relation locks.Robert Haas2011-07-18
| | | | | | | | | | | | | | | | | When an AccessShareLock, RowShareLock, or RowExclusiveLock is requested on an unshared database relation, and we can verify that no conflicting locks can possibly be present, record the lock in a per-backend queue, stored within the PGPROC, rather than in the primary lock table. This eliminates a great deal of contention on the lock manager LWLocks. This patch also refactors the interface between GetLockStatusData() and pg_lock_status() to be a bit more abstract, so that we don't rely so heavily on the lock manager's internal representation details. The new fast path lock structures don't have a LOCK or PROCLOCK structure to return, so we mustn't depend on that for purposes of listing outstanding locks. Review by Jeff Davis.
* Include pid in pg_lock_status() results even for SIREAD locks.Robert Haas2011-04-04
| | | | Dan Ports
* Add transaction-level advisory locks.Itagaki Takahiro2011-02-18
| | | | | | | | | They share the same locking namespace with the existing session-level advisory locks, but they are automatically released at the end of the current transaction and cannot be released explicitly via unlock functions. Marko Tiikkaja, reviewed by me.
* Implement genuine serializable isolation level.Heikki Linnakangas2011-02-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Until now, our Serializable mode has in fact been what's called Snapshot Isolation, which allows some anomalies that could not occur in any serialized ordering of the transactions. This patch fixes that using a method called Serializable Snapshot Isolation, based on research papers by Michael J. Cahill (see README-SSI for full references). In Serializable Snapshot Isolation, transactions run like they do in Snapshot Isolation, but a predicate lock manager observes the reads and writes performed and aborts transactions if it detects that an anomaly might occur. This method produces some false positives, ie. it sometimes aborts transactions even though there is no anomaly. To track reads we implement predicate locking, see storage/lmgr/predicate.c. Whenever a tuple is read, a predicate lock is acquired on the tuple. Shared memory is finite, so when a transaction takes many tuple-level locks on a page, the locks are promoted to a single page-level lock, and further to a single relation level lock if necessary. To lock key values with no matching tuple, a sequential scan always takes a relation-level lock, and an index scan acquires a page-level lock that covers the search key, whether or not there are any matching keys at the moment. A predicate lock doesn't conflict with any regular locks or with another predicate locks in the normal sense. They're only used by the predicate lock manager to detect the danger of anomalies. Only serializable transactions participate in predicate locking, so there should be no extra overhead for for other transactions. Predicate locks can't be released at commit, but must be remembered until all the transactions that overlapped with it have completed. That means that we need to remember an unbounded amount of predicate locks, so we apply a lossy but conservative method of tracking locks for committed transactions. If we run short of shared memory, we overflow to a new "pg_serial" SLRU pool. We don't currently allow Serializable transactions in Hot Standby mode. That would be hard, because even read-only transactions can cause anomalies that wouldn't otherwise occur. Serializable isolation mode now means the new fully serializable level. Repeatable Read gives you the old Snapshot Isolation level that we have always had. Kevin Grittner and Dan Ports, reviewed by Jeff Davis, Heikki Linnakangas and Anssi Kääriäinen
* Stamp copyrights for year 2011.Bruce Momjian2011-01-01
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* Remove cvs keywords from all files.Magnus Hagander2010-09-20
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* Update copyright for the year 2010.Bruce Momjian2010-01-02
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* Update copyright for 2009.Bruce Momjian2009-01-01
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* Remove all uses of the deprecated functions heap_formtuple, heap_modifytuple,Tom Lane2008-11-02
| | | | | | | | | | | and heap_deformtuple in favor of the newer functions heap_form_tuple et al (which do the same things but use bool control flags instead of arbitrary char values). Eliminate the former duplicate coding of these functions, reducing the deprecated functions to mere wrappers around the newer ones. We can't get rid of them entirely because add-on modules probably still contain many instances of the old coding style. Kris Jurka
* Restructure some header files a bit, in particular heapam.h, by removing someAlvaro Herrera2008-05-12
| | | | | | | | | | | | unnecessary #include lines in it. Also, move some tuple routine prototypes and macros to htup.h, which allows removal of heapam.h inclusion from some .c files. For this to work, a new header file access/sysattr.h needed to be created, initially containing attribute numbers of system columns, for pg_dump usage. While at it, make contrib ltree, intarray and hstore header files more consistent with our header style.
* Simplify and standardize conversions between TEXT datums and ordinary CTom Lane2008-03-25
| | | | | | | | | | | | | | | | | | | | strings. This patch introduces four support functions cstring_to_text, cstring_to_text_with_len, text_to_cstring, and text_to_cstring_buffer, and two macros CStringGetTextDatum and TextDatumGetCString. A number of existing macros that provided variants on these themes were removed. Most of the places that need to make such conversions now require just one function or macro call, in place of the multiple notational layers that used to be needed. There are no longer any direct calls of textout or textin, and we got most of the places that were using handmade conversions via memcpy (there may be a few still lurking, though). This commit doesn't make any serious effort to eliminate transient memory leaks caused by detoasting toasted text objects before they reach text_to_cstring. We changed PG_GETARG_TEXT_P to PG_GETARG_TEXT_PP in a few places where it was easy, but much more could be done. Brendan Jurd and Tom Lane
* lmgr.c:DescribeLockTag was never taught about virtual xids, per Greg Stark.Tom Lane2008-01-08
| | | | | Also a couple of minor tweaks to try to future-proof the code a bit better against future locktag additions.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* pgindent run for 8.3.Bruce Momjian2007-11-15
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* Implement lazy XID allocation: transactions that do not modify any databaseTom Lane2007-09-05
| | | | | | | | | | | | | | | rows will normally never obtain an XID at all. We already did things this way for subtransactions, but this patch extends the concept to top-level transactions. In applications where there are lots of short read-only transactions, this should improve performance noticeably; not so much from removal of the actual XID-assignments, as from reduction of overhead that's driven by the rate of XID consumption. We add a concept of a "virtual transaction ID" so that active transactions can be uniquely identified even if they don't have a regular XID. This is a much lighter-weight concept: uniqueness of VXIDs is only guaranteed over the short term, and no on-disk record is made about them. Florian Pflug, with some editorialization by Tom.
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* pgindent run for 8.2.Bruce Momjian2006-10-04
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* Fix pg_locks view to call advisory locks advisory locks, while preservingTom Lane2006-09-22
| | | | | backward compatibility for anyone using the old userlock code that's now on pgfoundry --- locks from that code still show as 'userlock'.
* Add built-in userlock manipulation functions to replace the formerTom Lane2006-09-18
| | | | | | | contrib functionality. Along the way, remove the USER_LOCKS configuration symbol, since it no longer makes any sense to try to compile that out. No user documentation yet ... mmoncure has promised to write some. Thanks to Abhijit Menon-Sen for creating a first draft to work from.
* Convert the lock manager to use the new dynahash.c support for partitionedTom Lane2006-07-23
| | | | | hash tables, instead of the previous kluge involving multiple hash tables. This partially undoes my patch of last December.
* Remove 576 references of include files that were not needed.Bruce Momjian2006-07-14
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* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Simplify lock manager data structures by making a clear separation betweenTom Lane2005-12-09
| | | | | | | | | | | | the data defining the semantics of a lock method (ie, conflict resolution table and ancillary data, which is all constant) and the hash tables storing the current state. The only thing we give up by this is the ability to use separate hashtables for different lock methods, but there is no need for that anyway. Put some extra fields into the LockMethod definition structs to clean up some other uglinesses, like hard-wired tests for DEFAULT_LOCKMETHOD and USER_LOCKMETHOD. This commit doesn't do anything about the performance issues we were discussing, but it clears away some of the underbrush that's in the way of fixing that.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Add a time-of-preparation column to the pg_prepared_xacts view, per anTom Lane2005-06-18
| | | | | | | | | | old suggestion by Oliver Jowett. Also, add a transaction column to the pg_locks view to show the xid of each transaction holding or awaiting locks; this allows prepared transactions to be properly associated with the locks they own. There was already a column named 'transaction', and I chose to rename it to 'transactionid' --- since this column is new in the current devel cycle there should be no backwards compatibility issue to worry about.
* Extend the pg_locks system view so that it can fully display all lockTom Lane2005-05-17
| | | | types, as per recent discussion.
* Restructure LOCKTAG as per discussions of a couple months ago.Tom Lane2005-04-29
| | | | | | | | | | | | | | Essentially, we shoehorn in a lockable-object-type field by taking a byte away from the lockmethodid, which can surely fit in one byte instead of two. This allows less artificial definitions of all the other fields of LOCKTAG; we can get rid of the special pg_xactlock pseudo-relation, and also support locks on individual tuples and general database objects (including shared objects). None of those possibilities are actually exploited just yet, however. I removed pg_xactlock from pg_class, but did not force initdb for that change. At this point, relkind 's' (SPECIAL) is unused and could be removed entirely.
* Update copyrights that were missed.Bruce Momjian2005-01-01
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* Update copyright to 2004.Bruce Momjian2004-08-29
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* Introduce local hash table for lock state, as per recent proposal.Tom Lane2004-08-27
| | | | | | | | | PROCLOCK structs in shared memory now have only a bitmask for held locks, rather than counts (making them 40 bytes smaller, which is a good thing). Multiple locks within a transaction are counted in the local hash table instead, and we have provision for tracking which ResourceOwner each count belongs to. Solves recently reported problem with memory leakage within long transactions.
* Replace TupleTableSlot convention for whole-row variables and functionTom Lane2004-04-01
| | | | | | | | results with tuples as ordinary varlena Datums. This commit does not in itself do much for us, except eliminate the horrid memory leak associated with evaluation of whole-row variables. However, it lays the groundwork for allowing composite types as table columns, and perhaps some other useful features as well. Per my proposal of a few days ago.