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2025-04-09Cleanup of pg_numa.cTomas Vondra
This moves/renames some of the functions defined in pg_numa.c: * pg_numa_get_pagesize() is renamed to pg_get_shmem_pagesize(), and moved to src/backend/storage/ipc/shmem.c. The new name better reflects that the page size is not related to NUMA, and it's specifically about the page size used for the main shared memory segment. * move pg_numa_available() to src/backend/storage/ipc/shmem.c, i.e. into the backend (which more appropriate for functions callable from SQL). While at it, improve the comment to explain what page size it returns. * remove unnecessary includes from src/port/pg_numa.c, adding unnecessary dependencies (src/port should be suitable for frontent). These were either leftovers or unnecessary thanks to the other changes in this commit. This eliminates unnecessary dependencies on backend symbols, which we don't want in src/port. Reported-by: Kirill Reshke <[email protected]> Reviewed-by: Andres Freund <[email protected]> https://postgr.es/m/CALdSSPi5fj0a7UG7Fmw2cUD1uWuckU_e8dJ+6x-bJEokcSXzqA@mail.gmail.com
2025-01-01Update copyright for 2025Bruce Momjian
Backpatch-through: 13
2024-11-26Improve InitShmemAccess() prototypePeter Eisentraut
The code comment said, 'the argument should be declared "PGShmemHeader *seghdr", but we use void to avoid having to include ipc.h in shmem.h.' We can achieve the original goal with a struct forward declaration. (ipc.h was also not the correct header file.) Discussion: https://www.postgresql.org/message-id/flat/cnthxg2eekacrejyeonuhiaezc7vd7o2uowlsbenxqfkjwgvwj@qgzu6eoqrglb
2024-07-02Improve some global variable declarationsPeter Eisentraut
We have in launch_backend.c: /* * The following need to be available to the save/restore_backend_variables * functions. They are marked NON_EXEC_STATIC in their home modules. */ extern slock_t *ShmemLock; extern slock_t *ProcStructLock; extern PGPROC *AuxiliaryProcs; extern PMSignalData *PMSignalState; extern pg_time_t first_syslogger_file_time; extern struct bkend *ShmemBackendArray; extern bool redirection_done; That comment is not completely true: ShmemLock, ShmemBackendArray, and redirection_done are not in fact NON_EXEC_STATIC. ShmemLock once was, but was then needed elsewhere. ShmemBackendArray was static inside postmaster.c before launch_backend.c was created. redirection_done was never static. This patch moves the declaration of ShmemLock and redirection_done to a header file. ShmemBackendArray gets a NON_EXEC_STATIC. This doesn't make a difference, since it only exists if EXEC_BACKEND anyway, but it makes it consistent. After that, the comment is now correct. Reviewed-by: Andres Freund <[email protected]> Discussion: https://www.postgresql.org/message-id/flat/[email protected]
2024-01-04Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
2023-01-20Remove SHM_QUEUEAndres Freund
Prior patches got rid of all the uses of SHM_QUEUE. ilist.h style lists are more widely used and have an easier to use interface. As there are no users left, remove SHM_QUEUE. Reviewed-by: Thomas Munro <[email protected]> (in an older version) Discussion: https://postgr.es/m/[email protected] Discussion: https://postgr.es/m/[email protected]
2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-01-08Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-01-02Update copyright for 2021Bruce Momjian
Backpatch-through: 9.5
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.
2020-01-09Add pg_shmem_allocations view.Robert Haas
This tells you about allocations that have been made from the main shared memory segment. The original patch also tried to show information about dynamic shared memory allocation as well, but I decided to leave that problem for another time. Andres Freund and Robert Haas, reviewed by Michael Paquier, Marti Raudsepp, Tom Lane, Álvaro Herrera, and Kyotaro Horiguchi. Discussion: http://postgr.es/m/[email protected]
2020-01-01Update copyrights for 2020Bruce Momjian
Backpatch-through: update all files in master, backpatch legal files through 9.4
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
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-01-03Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3
2017-06-21Phase 2 of pgindent updates.Tom Lane
Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. 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/[email protected] Discussion: https://postgr.es/m/[email protected]
2017-01-03Update copyright via script for 2017Bruce Momjian
2016-12-12Make the different Unix-y semaphore implementations ABI-compatible.Tom Lane
Previously, the "sem" field of PGPROC varied in size depending on which kernel semaphore API we were using. That was okay as long as there was only one likely choice per platform, but in the wake of commit ecb0d20a9, that assumption seems rather shaky. It doesn't seem out of the question anymore that an extension compiled against one API choice might be loaded into a postmaster built with another choice. Moreover, this prevents any possibility of selecting the semaphore API at postmaster startup, which might be something we want to do in future. Hence, change PGPROC.sem to be PGSemaphore (i.e. a pointer) for all Unix semaphore APIs, and turn the pointed-to data into an opaque struct whose contents are only known within the responsible modules. For the SysV and unnamed-POSIX APIs, the pointed-to data has to be allocated elsewhere in shared memory, which takes a little bit of rejiggering of the InitShmemAllocation code sequence. (I invented a ShmemAllocUnlocked() function to make that a little cleaner than it used to be. That function is not meant for any uses other than the ones it has now, but it beats having InitShmemAllocation() know explicitly about allocation of space for semaphores and spinlocks.) This change means an extra indirection to access the semaphore data, but since we only touch that when blocking or awakening a process, there shouldn't be any meaningful performance penalty. Moreover, at least for the unnamed-POSIX case on Linux, the sem_t type is quite a bit wider than a pointer, so this reduces sizeof(PGPROC) which seems like a good thing. For the named-POSIX API, there's effectively no change: the PGPROC.sem field was and still is a pointer to something returned by sem_open() in the postmaster's memory space. Document and check the pre-existing limitation that this case can't work in EXEC_BACKEND mode. It did not seem worth unifying the Windows semaphore ABI with the Unix cases, since there's no likelihood of needing ABI compatibility much less runtime switching across those cases. However, we can simplify the Windows code a bit if we define PGSemaphore as being directly a HANDLE, rather than pointer to HANDLE, so let's do that while we're here. (This also ends up being no change in what's physically stored in PGPROC.sem. We're just moving the HANDLE fetch from callees to callers.) It would take a bunch of additional code shuffling to get to the point of actually choosing a semaphore API at postmaster start, but the effects of that would now be localized in the port/XXX_sema.c files, so it seems like fit material for a separate patch. The need for it is unproven as yet, anyhow, whereas the ABI risk to extensions seems real enough. Discussion: https://postgr.es/m/[email protected]
2016-09-01Change API of ShmemAlloc() so it throws error rather than returning NULL.Tom Lane
A majority of callers seem to have believed that this was the API spec already, because they omitted any check for a NULL result, and hence would crash on an out-of-shared-memory failure. The original proposal was to just add such error checks everywhere, but that does nothing to prevent similar omissions in future. Instead, let's make ShmemAlloc() throw the error (so we can remove the caller-side checks that do exist), and introduce a new function ShmemAllocNoError() that has the previous behavior of returning NULL, for the small number of callers that need that and are prepared to do the right thing. This also lets us remove the rather wishy-washy behavior of printing a WARNING for out-of-shmem, which never made much sense: either the caller has a strategy for dealing with that, or it doesn't. It's not ShmemAlloc's business to decide whether a warning is appropriate. The v10 release notes will need to call this out as a significant source-code change. It's likely that it will be a bug fix for extension callers too, but if not, they'll need to change to using ShmemAllocNoError(). This is nominally a bug fix, but the odds that it's fixing any live bug are actually rather small, because in general the requests being made by the unchecked callers were already accounted for in determining the overall shmem size, so really they ought not fail. Between that and the possible impact on extensions, no back-patch. Discussion: <[email protected]>
2016-01-02Update copyright for 2016Bruce Momjian
Backpatch certain files through 9.1
2015-01-06Update copyright for 2015Bruce Momjian
Backpatch certain files through 9.0
2014-01-07Update copyright for 2014Bruce Momjian
Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
2013-01-01Update copyrights for 2013Bruce Momjian
Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
2012-01-01Update copyright notices for year 2012.Bruce Momjian
2011-03-31Increase SHMEM_INDEX_SIZE from 32 to 64. We're currently at 40 entries inHeikki Linnakangas
ShmemIndex, so 64 leaves some headroom. Kevin Grittner
2011-03-06Efficient transaction-controlled synchronous replication.Simon Riggs
If a standby is broadcasting reply messages and we have named one or more standbys in synchronous_standby_names then allow users who set synchronous_replication to wait for commit, which then provides strict data integrity guarantees. Design avoids sending and receiving transaction state information so minimises bookkeeping overheads. We synchronize with the highest priority standby that is connected and ready to synchronize. Other standbys can be defined to takeover in case of standby failure. This version has very strict behaviour; more relaxed options may be added at a later date. Simon Riggs and Fujii Masao, with reviews by Yeb Havinga, Jaime Casanova, Heikki Linnakangas and Robert Haas, plus the assistance of many other design reviewers.
2011-02-07Implement genuine serializable isolation level.Heikki Linnakangas
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
2011-01-01Stamp copyrights for year 2011.Bruce Momjian
2010-09-20Remove cvs keywords from all files.Magnus Hagander
2010-01-02Update copyright for the year 2010.Bruce Momjian
2009-06-118.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian
provided by Andrew.
2009-01-01Update copyright for 2009.Bruce Momjian
2008-11-02Remove the last vestiges of the MAKE_PTR/MAKE_OFFSET mechanism. We haven'tTom Lane
allowed different processes to have different addresses for the shmem segment in quite a long time, but there were still a few places left that used the old coding convention. Clean them up to reduce confusion and improve the compiler's ability to detect pointer type mismatches. Kris Jurka
2008-01-01Update copyrights in source tree to 2008.Bruce Momjian
2007-07-25Rename DLLIMPORT macro to PGDLLIMPORT to avoid conflict withMagnus Hagander
third party includes (like tcl) that define DLLIMPORT.
2007-06-25Remove unused BAD_LOCATION definition.Alvaro Herrera
2007-01-05Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian
back-stamped for this.
2006-10-15Redesign the patch for allocation of shmem space and LWLocks for add-onTom Lane
modules; the first try was not usable in EXEC_BACKEND builds (e.g., Windows). Instead, just provide some entry points to increase the allocation requests during postmaster start, and provide a dedicated LWLock that can be used to synchronize allocation operations performed by backends. Per discussion with Marc Munro.
2006-08-01Add support for loadable modules to allocated shared memory andBruce Momjian
lightweight locks. Marc Munro
2006-03-05Update copyright for 2006. Update scripts.Bruce Momjian
2006-01-04Rearrange backend startup sequence so that ShmemIndexLock can becomeTom Lane
an LWLock instead of a spinlock. This hardly matters on Unix machines but should improve startup performance on Windows (or any port using EXEC_BACKEND). Per previous discussion.
2005-08-20Convert the arithmetic for shared memory size calculation from 'int'Tom Lane
to 'Size' (that is, size_t), and install overflow detection checks in it. This allows us to remove the former arbitrary restrictions on NBuffers etc. It won't make any difference in a 32-bit machine, but in a 64-bit machine you could theoretically have terabytes of shared buffers. (How efficiently we could manage 'em remains to be seen.) Similarly, num_temp_buffers, work_mem, and maintenance_work_mem can be set above 2Gb on a 64-bit machine. Original patch from Koichi Suzuki, additional work by moi.
2004-12-31Tag appropriate files for rc3PostgreSQL Daemon
Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
2004-09-28Arrange to preallocate all required space for the buffer and FSM hashTom Lane
tables in shared memory. This ensures that overflow of the lock table creates no long-lasting problems. Per discussion with Merlin Moncure.
2004-08-29Update copyright to 2004.Bruce Momjian
2003-12-20This patch is the next step towards (re)allowing fork/exec.Bruce Momjian
Claudio Natoli
2003-11-29make sure the $Id tags are converted to $PostgreSQL as well ...PostgreSQL Daemon
2003-08-04Update copyrights to 2003.Bruce Momjian
2002-08-17[ Newest version of patch applied.]Bruce Momjian
This patch is an updated version of the lock listing patch. I've made the following changes: - write documentation - wrap the SRF in a view called 'pg_locks': all user-level access should be done through this view - re-diff against latest CVS One thing I chose not to do is adapt the SRF to use the anonymous composite type code from Joe Conway. I'll probably do that eventually, but I'm not really convinced it's a significantly cleaner way to bootstrap SRF builtins than the method this patch uses (of course, it has other uses...) Neil Conway
2002-06-20Update copyright to 2002.Bruce Momjian