summaryrefslogtreecommitdiff
path: root/src/backend/utils/init
AgeCommit message (Collapse)Author
2024-10-07Fix Y2038 issues with MyStartTime.Nathan Bossart
Several places treat MyStartTime as a "long", which is only 32 bits wide on some platforms. In reality, MyStartTime is a pg_time_t, i.e., a signed 64-bit integer. This will lead to interesting bugs on the aforementioned systems in 2038 when signed 32-bit integers are no longer sufficient to store Unix time (e.g., "pg_ctl start" hanging). To fix, ensure that MyStartTime is handled as a 64-bit value everywhere. (Of course, users will need to ensure that time_t is 64 bits wide on their system, too.) Co-authored-by: Max Johnson Discussion: https://postgr.es/m/CO1PR07MB905262E8AC270FAAACED66008D682%40CO1PR07MB9052.namprd07.prod.outlook.com Backpatch-through: 12
2024-09-21Increase the number of fast-path lock slotsTomas Vondra
Replace the fixed-size array of fast-path locks with arrays, sized on startup based on max_locks_per_transaction. This allows using fast-path locking for workloads that need more locks. The fast-path locking introduced in 9.2 allowed each backend to acquire a small number (16) of weak relation locks cheaply. If a backend needs to hold more locks, it has to insert them into the shared lock table. This is considerably more expensive, and may be subject to contention (especially on many-core systems). The limit of 16 fast-path locks was always rather low, because we have to lock all relations - not just tables, but also indexes, views, etc. For planning we need to lock all relations that might be used in the plan, not just those that actually get used in the final plan. So even with rather simple queries and schemas, we often need significantly more than 16 locks. As partitioning gets used more widely, and the number of partitions increases, this limit is trivial to hit. Complex queries may easily use hundreds or even thousands of locks. For workloads doing a lot of I/O this is not noticeable, but for workloads accessing only data in RAM, the access to the shared lock table may be a serious issue. This commit removes the hard-coded limit of the number of fast-path locks. Instead, the size of the fast-path arrays is calculated at startup, and can be set much higher than the original 16-lock limit. The overall fast-path locking protocol remains unchanged. The variable-sized fast-path arrays can no longer be part of PGPROC, but are allocated as a separate chunk of shared memory and then references from the PGPROC entries. The fast-path slots are organized as a 16-way set associative cache. You can imagine it as a hash table of 16-slot "groups". Each relation is mapped to exactly one group using hash(relid), and the group is then processed using linear search, just like the original fast-path cache. With only 16 entries this is cheap, with good locality. Treating this as a simple hash table with open addressing would not be efficient, especially once the hash table gets almost full. The usual remedy is to grow the table, but we can't do that here easily. The access would also be more random, with worse locality. The fast-path arrays are sized using the max_locks_per_transaction GUC. We try to have enough capacity for the number of locks specified in the GUC, using the traditional 2^n formula, with an upper limit of 1024 lock groups (i.e. 16k locks). The default value of max_locks_per_transaction is 64, which means those instances will have 64 fast-path slots. The main purpose of the max_locks_per_transaction GUC is to size the shared lock table. It is often set to the "average" number of locks needed by backends, with some backends using significantly more locks. This should not be a major issue, however. Some backens may have to insert locks into the shared lock table, but there can't be too many of them, limiting the contention. The only solution is to increase the GUC, even if the shared lock table already has sufficient capacity. That is not free, especially in terms of memory usage (the shared lock table entries are fairly large). It should only happen on machines with plenty of memory, though. In the future we may consider a separate GUC for the number of fast-path slots, but let's try without one first. Reviewed-by: Robert Haas, Jakub Wartak Discussion: https://postgr.es/m/510b887e-c0ce-4a0c-a17a-2c6abb8d9a5c@enterprisedb.com
2024-08-29Rename some shared memory initialization routinesHeikki Linnakangas
To make them follow the usual naming convention where FoobarShmemSize() calculates the amount of shared memory needed by Foobar subsystem, and FoobarShmemInit() performs the initialization. I didn't rename CreateLWLocks() and InitShmmeIndex(), because they are a little special. They need to be called before any of the other ShmemInit() functions, because they set up the shared memory bookkeeping itself. I also didn't rename InitProcGlobal(), because unlike other Shmeminit functions, it's not called by individual backends. Reviewed-by: Andreas Karlsson Discussion: https://www.postgresql.org/message-id/c09694ff-2453-47e5-b26c-32a16cd75ce6@iki.fi
2024-08-29Refactor lock manager initialization to make it a bit less specialHeikki Linnakangas
Split the shared and local initialization to separate functions, and follow the common naming conventions. With this, we no longer create the LockMethodLocalHash hash table in the postmaster process, which was always pointless. Reviewed-by: Andreas Karlsson Discussion: https://www.postgresql.org/message-id/c09694ff-2453-47e5-b26c-32a16cd75ce6@iki.fi
2024-08-13Use pgBufferUsage for buffer usage tracking in analyze.Masahiko Sawada
Previously, (auto)analyze used global variables VacuumPageHit, VacuumPageMiss, and VacuumPageDirty to track buffer usage. However, pgBufferUsage provides a more generic way to track buffer usage with support functions. This change replaces those global variables with pgBufferUsage in analyze. Since analyze was the sole user of those variables, it removes their declarations. Vacuum previously used those variables but replaced them with pgBufferUsage as part of a bug fix, commit 5cd72cc0c. Additionally, it adjusts the buffer usage message in both vacuum and analyze for better consistency. Author: Anthonin Bonnefoy Reviewed-by: Masahiko Sawada, Michael Paquier Discussion: https://postgr.es/m/CAO6_Xqr__kTTCLkftqS0qSCm-J7_xbRG3Ge2rWhucxQJMJhcRA%40mail.gmail.com
2024-07-29Move cancel key generation to after forking the backendHeikki Linnakangas
Move responsibility of generating the cancel key to the backend process. The cancel key is now generated after forking, and the backend advertises it in the ProcSignal array. When a cancel request arrives, the backend handling it scans the ProcSignal array to find the target pid and cancel key. This is similar to how this previously worked in the EXEC_BACKEND case with the ShmemBackendArray, just reusing the ProcSignal array. One notable change is that we no longer generate cancellation keys for non-backend processes. We generated them before just to prevent a malicious user from canceling them; the keys for non-backend processes were never actually given to anyone. There is now an explicit flag indicating whether a process has a valid key or not. I wrote this originally in preparation for supporting longer cancel keys, but it's a nice cleanup on its own. Reviewed-by: Jelte Fennema-Nio Discussion: https://www.postgresql.org/message-id/508d0505-8b7a-4864-a681-e7e5edfe32aa@iki.fi
2024-07-28Refactor: make default_locale internal to pg_locale.c.Jeff Davis
Discussion: https://postgr.es/m/2228884bb1f1a02614b39f71a90c94d2cc8a3a2f.camel@j-davis.com Reviewed-by: Peter Eisentraut, Andreas Karlsson
2024-07-05Remove check hooks for GUCs that contribute to MaxBackends.Nathan Bossart
Each of max_connections, max_worker_processes, autovacuum_max_workers, and max_wal_senders has a GUC check hook that verifies the sum of those GUCs does not exceed a hard-coded limit (see the comment for MAX_BACKENDS in postmaster.h). In general, the hooks effectively guard against egregious misconfigurations. However, this approach has some problems. Since these check hooks are called as each GUC is assigned its user-specified value, only one of the hooks will be called with all the relevant GUCs set. If one or more of the user-specified values are less than the initial values of the GUCs' underlying variables, false positives can occur. Furthermore, the error message emitted when one of the check hooks fails is not tremendously helpful. For example, the command $ pg_ctl -D . start -o "-c max_connections=262100 -c max_wal_senders=10000" fails with the following error: FATAL: invalid value for parameter "max_wal_senders": 10000 Fortunately, there is an extra copy of this check in InitializeMaxBackends() that we can rely on, so this commit removes the aforementioned GUC check hooks in favor of that one. It also enhances the error message to clearly show the values of the relevant GUCs and the hard-coded limit their sum may not exceed. The downside of this change is that server startup progresses further before failing due to such misconfigurations (thus taking longer), but these failures are expected to be rare, so we don't anticipate any real harm in practice. Reviewed-by: Tom Lane Discussion: https://postgr.es/m/ZnMr2k-Nk5vj7T7H%40nathan
2024-07-02Add missing includes for some global variablesPeter Eisentraut
src/backend/libpq/pqcomm.c: "postmaster/postmaster.h" for Unix_socket_group, Unix_socket_permissions src/backend/utils/init/globals.c: "postmaster/postmaster.h" for MyClientSocket src/backend/utils/misc/guc_tables.c: "utils/rls.h" for row_security src/backend/utils/sort/tuplesort.c: "utils/guc.h" for trace_sort Nothing currently diagnoses missing includes for global variables, but this is being cleaned up, and these ones had an obvious header file available. Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://www.postgresql.org/message-id/flat/e0a62134-83da-4ba4-8cdb-ceb0111c95ce@eisentraut.org
2024-04-06Increase default vacuum_buffer_usage_limit to 2MB.Thomas Munro
The BAS_VACUUM ring size has been 256kB since commit d526575f introduced the mechanism 17 years ago. Commit 1cbbee03 recently made it configurable but retained the traditional default. The correct default size has been debated for years, but 256kB is certainly very small. VACUUM soon needs to write back data it dirtied only 32 blocks ago, which usually requires flushing the WAL. New experiments in prefetching pages for VACUUM exacerbated the problem by crashing into dirty data even sooner. Let's make the default 2MB. That's 1.6% of the default toy buffer pool size, and 0.2% of 1GB, which would be a considered a small shared_buffers setting for a real system these days. Users are still free to set the GUC to a different value. Reviewed-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/20240403221257.md4gfki3z75cdyf6%40awork3.anarazel.de Discussion: https://postgr.es/m/CA%2BhUKGLY4Q4ZY4f1rvnFtv6%2BPkjNf8MejdPkcju3Qii9DYqqcQ%40mail.gmail.com
2024-03-18Refactor postmaster child process launchingHeikki Linnakangas
Introduce new postmaster_child_launch() function that deals with the differences in EXEC_BACKEND mode. Refactor the mechanism of passing information from the parent to child process. Instead of using different command-line arguments when launching the child process in EXEC_BACKEND mode, pass a variable-length blob of startup data along with all the global variables. The contents of that blob depend on the kind of child process being launched. In !EXEC_BACKEND mode, we use the same blob, but it's simply inherited from the parent to child process. Reviewed-by: Tristan Partin, Andres Freund Discussion: https://www.postgresql.org/message-id/7a59b073-5b5b-151e-7ed3-8b01ff7ce9ef@iki.fi
2024-03-13Introduce "builtin" collation provider.Jeff Davis
New provider for collations, like "libc" or "icu", but without any external dependency. Initially, the only locale supported by the builtin provider is "C", which is identical to the libc provider's "C" locale. The libc provider's "C" locale has always been treated as a special case that uses an internal implementation, without using libc at all -- so the new builtin provider uses the same implementation. The builtin provider's locale is independent of the server environment variables LC_COLLATE and LC_CTYPE. Using the builtin provider, the database collation locale can be "C" while LC_COLLATE and LC_CTYPE are set to "en_US", which is impossible with the libc provider. By offering a new builtin provider, it clarifies that the semantics of a collation using this provider will never depend on libc, and makes it easier to document the behavior. Discussion: https://postgr.es/m/ab925f69-5f9d-f85e-b87c-bd2a44798659@joeconway.com Discussion: https://postgr.es/m/dd9261f4-7a98-4565-93ec-336c1c110d90@manitou-mail.org Discussion: https://postgr.es/m/ff4c2f2f9c8fc7ca27c1c24ae37ecaeaeaff6b53.camel%40j-davis.com Reviewed-by: Daniel Vérité, Peter Eisentraut, Jeremy Schneider
2024-03-09Catalog changes preparing for builtin collation provider.Jeff Davis
Rename pg_collation.colliculocale to colllocale, and pg_database.daticulocale to datlocale. These names reflects that the fields will be useful for the upcoming builtin provider as well, not just for ICU. This is purely a rename; no changes to the meaning of the fields. Discussion: https://postgr.es/m/ff4c2f2f9c8fc7ca27c1c24ae37ecaeaeaff6b53.camel%40j-davis.com Reviewed-by: Peter Eisentraut
2024-03-04Remove unused #include's from backend .c filesPeter Eisentraut
as determined by include-what-you-use (IWYU) While IWYU also suggests to *add* a bunch of #include's (which is its main purpose), this patch does not do that. In some cases, a more specific #include replaces another less specific one. Some manual adjustments of the automatic result: - IWYU currently doesn't know about includes that provide global variable declarations (like -Wmissing-variable-declarations), so those includes are being kept manually. - All includes for port(ability) headers are being kept for now, to play it safe. - No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the patch from exploding in size. Note that this patch touches just *.c files, so nothing declared in header files changes in hidden ways. As a small example, in src/backend/access/transam/rmgr.c, some IWYU pragma annotations are added to handle a special case there. Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
2024-03-04Use MyBackendType in more places to check what process this isHeikki Linnakangas
Remove IsBackgroundWorker, IsAutoVacuumLauncherProcess(), IsAutoVacuumWorkerProcess(), and IsLogicalSlotSyncWorker() in favor of new Am*Process() macros that use MyBackendType. For consistency with the existing Am*Process() macros. Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/f3ecd4cb-85ee-4e54-8278-5fabfb3a4ed0@iki.fi
2024-03-03Replace BackendIds with 0-based ProcNumbersHeikki Linnakangas
Now that BackendId was just another index into the proc array, it was redundant with the 0-based proc numbers used in other places. Replace all usage of backend IDs with proc numbers. The only place where the term "backend id" remains is in a few pgstat functions that expose backend IDs at the SQL level. Those IDs are now in fact 0-based ProcNumbers too, but the documentation still calls them "backend ids". That term still seems appropriate to describe what the numbers are, so I let it be. One user-visible effect is that pg_temp_0 is now a valid temp schema name, for backend with ProcNumber 0. Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/8171f1aa-496f-46a6-afc3-c46fe7a9b407@iki.fi
2024-03-03Redefine backend ID to be an index into the proc arrayHeikki Linnakangas
Previously, backend ID was an index into the ProcState array, in the shared cache invalidation manager (sinvaladt.c). The entry in the ProcState array was reserved at backend startup by scanning the array for a free entry, and that was also when the backend got its backend ID. Things become slightly simpler if we redefine backend ID to be the index into the PGPROC array, and directly use it also as an index to the ProcState array. This uses a little more memory, as we reserve a few extra slots in the ProcState array for aux processes that don't need them, but the simplicity is worth it. Aux processes now also have a backend ID. This simplifies the reservation of BackendStatusArray and ProcSignal slots. You can now convert a backend ID into an index into the PGPROC array simply by subtracting 1. We still use 0-based "pgprocnos" in various places, for indexes into the PGPROC array, but the only difference now is that backend IDs start at 1 while pgprocnos start at 0. (The next commmit will get rid of the term "backend ID" altogether and make everything 0-based.) There is still a 'backendId' field in PGPROC, now part of 'vxid' which encapsulates the backend ID and local transaction ID together. It's needed for prepared xacts. For regular backends, the backendId is always equal to pgprocno + 1, but for prepared xact PGPROC entries, it's the ID of the original backend that processed the transaction. Reviewed-by: Andres Freund, Reid Thompson Discussion: https://www.postgresql.org/message-id/8171f1aa-496f-46a6-afc3-c46fe7a9b407@iki.fi
2024-02-28Improve performance of subsystems on top of SLRUAlvaro Herrera
More precisely, what we do here is make the SLRU cache sizes configurable with new GUCs, so that sites with high concurrency and big ranges of transactions in flight (resp. multixacts/subtransactions) can benefit from bigger caches. In order for this to work with good performance, two additional changes are made: 1. the cache is divided in "banks" (to borrow terminology from CPU caches), and algorithms such as eviction buffer search only affect one specific bank. This forestalls the problem that linear searching for a specific buffer across the whole cache takes too long: we only have to search the specific bank, whose size is small. This work is authored by Andrey Borodin. 2. Change the locking regime for the SLRU banks, so that each bank uses a separate LWLock. This allows for increased scalability. This work is authored by Dilip Kumar. (A part of this was previously committed as d172b717c6f4.) Special care is taken so that the algorithms that can potentially traverse more than one bank release one bank's lock before acquiring the next. This should happen rarely, but particularly clog.c's group commit feature needed code adjustment to cope with this. I (Álvaro) also added lots of comments to make sure the design is sound. The new GUCs match the names introduced by bcdfa5f2e2f2 in the pg_stat_slru view. The default values for these parameters are similar to the previous sizes of each SLRU. commit_ts, clog and subtrans accept value 0, which means to adjust by dividing shared_buffers by 512 (so 2MB for every 1GB of shared_buffers), with a cap of 8MB. (A new slru.c function SimpleLruAutotuneBuffers() was added to support this.) The cap was previously 1MB for clog, so for sites with more than 512MB of shared memory the total memory used increases, which is likely a good tradeoff. However, other SLRUs (notably multixact ones) retain smaller sizes and don't support a configured value of 0. These values based on shared_buffers may need to be revisited, but that's an easy change. There was some resistance to adding these new GUCs: it would be better to adjust to memory pressure automatically somehow, for example by stealing memory from shared_buffers (where the caches can grow and shrink naturally). However, doing that seems to be a much larger project and one which has made virtually no progress in several years, and because this is such a pain point for so many users, here we take the pragmatic approach. Author: Andrey Borodin <x4mmm@yandex-team.ru> Author: Dilip Kumar <dilipbalaut@gmail.com> Reviewed-by: Amul Sul, Gilles Darold, Anastasia Lubennikova, Ivan Lazarev, Robert Haas, Thomas Munro, Tomas Vondra, Yura Sokolov, Васильев Дмитрий (Dmitry Vasiliev). Discussion: https://postgr.es/m/2BEC2B3F-9B61-4C1D-9FB5-5FAB0F05EF86@yandex-team.ru Discussion: https://postgr.es/m/CAFiTN-vzDvNz=ExGXz6gdyjtzGixKSqs0mKHMmaQ8sOSEFZ33A@mail.gmail.com
2024-02-22Add a new slot sync worker to synchronize logical slots.Amit Kapila
By enabling slot synchronization, all the failover logical replication slots on the primary (assuming configurations are appropriate) are automatically created on the physical standbys and are synced periodically. The slot sync worker on the standby server pings the primary server at regular intervals to get the necessary failover logical slots information and create/update the slots locally. The slots that no longer require synchronization are automatically dropped by the worker. The nap time of the worker is tuned according to the activity on the primary. The slot sync worker waits for some time before the next synchronization, with the duration varying based on whether any slots were updated during the last cycle. A new parameter sync_replication_slots enables or disables this new process. On promotion, the slot sync worker is shut down by the startup process to drop any temporary slots acquired by the slot sync worker and to prevent the worker from trying to fetch the failover slots. A functionality to allow logical walsenders to wait for the physical will be done in a subsequent commit. Author: Shveta Malik, Hou Zhijie based on design inputs by Masahiko Sawada and Amit Kapila Reviewed-by: Masahiko Sawada, Bertrand Drouvot, Peter Smith, Dilip Kumar, Ajin Cherian, Nisha Moond, Kuroda Hayato, Amit Kapila Discussion: https://postgr.es/m/514f6f2f-6833-4539-39f1-96cd1e011f23@enterprisedb.com
2024-02-15Introduce transaction_timeoutAlexander Korotkov
This commit adds timeout that is expected to be used as a prevention of long-running queries. Any session within the transaction will be terminated after spanning longer than this timeout. However, this timeout is not applied to prepared transactions. Only transactions with user connections are affected. Discussion: https://postgr.es/m/CAAhFRxiQsRs2Eq5kCo9nXE3HTugsAAJdSQSmxncivebAxdmBjQ%40mail.gmail.com Author: Andrey Borodin <amborodin@acm.org> Author: Japin Li <japinli@hotmail.com> Author: Junwang Zhao <zhjwpku@gmail.com> Reviewed-by: Nikolay Samokhvalov <samokhvalov@gmail.com> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com> Reviewed-by: bt23nguyent <bt23nguyent@oss.nttdata.com> Reviewed-by: Yuhang Qiu <iamqyh@gmail.com>
2024-01-03Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
2023-12-20Add a new WAL summarizer process.Robert Haas
When active, this process writes WAL summary files to $PGDATA/pg_wal/summaries. Each summary file contains information for a certain range of LSNs on a certain TLI. For each relation, it stores a "limit block" which is 0 if a relation is created or destroyed within a certain range of WAL records, or otherwise the shortest length to which the relation was truncated during that range of WAL records, or otherwise InvalidBlockNumber. In addition, it stores a list of blocks which have been modified during that range of WAL records, but excluding blocks which were removed by truncation after they were modified and never subsequently modified again. In other words, it tells us which blocks need to copied in case of an incremental backup covering that range of WAL records. But this doesn't yet add the capability to actually perform an incremental backup; the next patch will do that. A new parameter summarize_wal enables or disables this new background process. The background process also automatically deletes summary files that are older than wal_summarize_keep_time, if that parameter has a non-zero value and the summarizer is configured to run. Patch by me, with some design help from Dilip Kumar and Andres Freund. Reviewed by Matthias van de Meent, Dilip Kumar, Jakub Wartak, Peter Eisentraut, and Álvaro Herrera. Discussion: http://postgr.es/m/CA+TgmoYOYZfMCyOXFyC-P+-mdrZqm5pP2N7S-r0z3_402h9rsA@mail.gmail.com
2023-12-01Adjust obsolete comment explaining set_stack_base().Thomas Munro
Commit 7389aad6 removed the notion of backends started from inside a signal handler. A stray comment still referred to them, while explaining the need for a call to set_stack_base(). That leads to the question of whether we still need the call in !EXEC_BACKEND builds. There doesn't seem to be much point in suppressing it now, as it doesn't hurt and probably helps to measure the stack base from the exact same place in EXEC_BACKEND and !EXEC_BACKEND builds. Back-patch to 16. Reported-by: Heikki Linnakangas <hlinnaka@iki.fi> Reported-by: Tristan Partin <tristan@neon.tech> Reported-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/CA%2BhUKG%2BEJHcevNGNOxVWxTNFbuB%3Dvjf4U68%2B85rAC_Sxvy2zEQ%40mail.gmail.com
2023-11-06Set GUC "is_superuser" in all processes that set AuthenticatedUserId.Noah Misch
It was always false in single-user mode, in autovacuum workers, and in background workers. This had no specifically-identified security consequences, but non-core code or future work might make it security-relevant. Back-patch to v11 (all supported versions). Jelte Fennema-Nio. Reported by Jelte Fennema-Nio.
2023-10-16Add support event triggers on authenticated loginAlexander Korotkov
This commit introduces trigger on login event, allowing to fire some actions right on the user connection. This can be useful for logging or connection check purposes as well as for some personalization of environment. Usage details are described in the documentation included, but shortly usage is the same as for other triggers: create function returning event_trigger and then create event trigger on login event. In order to prevent the connection time overhead when there are no triggers the commit introduces pg_database.dathasloginevt flag, which indicates database has active login triggers. This flag is set by CREATE/ALTER EVENT TRIGGER command, and unset at connection time when no active triggers found. Author: Konstantin Knizhnik, Mikhail Gribkov Discussion: https://postgr.es/m/0d46d29f-4558-3af9-9c85-7774e14a7709%40postgrespro.ru Reviewed-by: Pavel Stehule, Takayuki Tsunakawa, Greg Nancarrow, Ivan Panchenko Reviewed-by: Daniel Gustafsson, Teodor Sigaev, Robert Haas, Andres Freund Reviewed-by: Tom Lane, Andrey Sokolov, Zhihong Yu, Sergey Shinderuk Reviewed-by: Gregory Stark, Nikita Malakhov, Ted Yu
2023-10-12Add option to bgworkers to allow the bypass of role login checkMichael Paquier
This adds a new option called BGWORKER_BYPASS_ROLELOGINCHECK to the flags available to BackgroundWorkerInitializeConnection() and BackgroundWorkerInitializeConnectionByOid(). This gives the possibility to bgworkers to bypass the role login check, making possible the use of a role that has no login rights while not being a superuser. PostgresInit() gains a new flag called INIT_PG_OVERRIDE_ROLE_LOGIN, taking advantage of the refactoring done in 4800a5dfb4c4. Regression tests are added to worker_spi to check the behavior of this new option with bgworkers. Author: Bertrand Drouvot Reviewed-by: Nathan Bossart, Michael Paquier, Bharath Rupireddy Discussion: https://postgr.es/m/bcc36259-7850-4882-97ef-d6b905d2fc51@gmail.com
2023-10-11Refactor InitPostgres() to use bitwise option flagsMichael Paquier
InitPostgres() has been using a set of boolean arguments to control its behavior, and a patch under discussion was aiming at expanding it with a third one. In preparation for expanding this area, this commit switches all the current boolean arguments of this routine to a single bits32 argument instead. Two values are currently supported for the flags: - INIT_PG_LOAD_SESSION_LIBS to load [session|local]_preload_libraries at startup. - INIT_PG_OVERRIDE_ALLOW_CONNS to allow connection to a database even if it has !datallowconn. This is used by bgworkers. Reviewed-by: Bertrand Drouvot Discussion: https://postgr.es/m/ZSTn66_BXRZCeaqS@paquier.xyz
2023-09-04Fix handling of shared statistics with dropped databasesMichael Paquier
Dropping a database while a connection is attempted on it was able to lead to the presence of valid database entries in shared statistics. The issue is that MyDatabaseId was getting set too early than it should, as, if the connection attempted on the dropped database fails when renamed or dropped, the shutdown callback of the shared statistics would finish by re-inserting a correct entry related to the database already dropped. As analyzed by the bug reporters, this issue could lead to phantom entries in the database list maintained by the autovacuum launcher (in rebuild_database_list()) if the database dropped was part of the database list when it was still valid. After the database was dropped, it would remain the highest on the list of databases to considered by the autovacuum worker as things to process. This would prevent autovacuum jobs to happen on all the other databases still present. The commit fixes this issue by delaying setting MyDatabaseId until the database existence has been re-checked with the second scan on pg_database after getting a shared lock on it, and by switching pgstat_update_dbstats() so as nothing happens if MyDatabaseId is not valid. Issue introduced by 5891c7a8ed8f, so backpatch down to 15. Reported-by: Will Mortensen, Jacob Speidel Analyzed-by: Will Mortensen, Jacob Speidel Author: Andres Freund Discussion: https://postgr.es/m/17973-bca1f7d5c14f601e@postgresql.org Backpatch-through: 15
2023-07-13Fix privilege check for SET SESSION AUTHORIZATION.Nathan Bossart
Presently, the privilege check for SET SESSION AUTHORIZATION checks whether the original authenticated role was a superuser at connection start time. Even if the role loses the superuser attribute, its existing sessions are permitted to change session authorization to any role. This commit modifies this privilege check to verify the original authenticated role currently has superuser. In the event that the authenticated role loses superuser within a session authorization change, the authorization change will remain in effect, which means the user can still take advantage of the target role's privileges. However, [RE]SET SESSION AUTHORIZATION will only permit switching to the original authenticated role. Author: Joseph Koshakow Discussion: https://postgr.es/m/CAAvxfHc-HHzONQ2oXdvhFF9ayRnidPwK%2BfVBhRzaBWYYLVQL-g%40mail.gmail.com
2023-07-13Move privilege check for SET SESSION AUTHORIZATION.Nathan Bossart
Presently, the privilege check for SET SESSION AUTHORIZATION is performed in session_authorization's assign_hook. A relevant comment states, "It's OK because the check does not require catalog access and can't fail during an end-of-transaction GUC reversion..." However, we plan to add a catalog lookup to this privilege check in a follow-up commit. This commit moves this privilege check to the check_hook for session_authorization. Like check_role(), we do not throw a hard error for insufficient privileges when the source is PGC_S_TEST. Author: Joseph Koshakow Discussion: https://postgr.es/m/CAAvxfHc-HHzONQ2oXdvhFF9ayRnidPwK%2BfVBhRzaBWYYLVQL-g%40mail.gmail.com
2023-07-13Handle DROP DATABASE getting interruptedAndres Freund
Until now, when DROP DATABASE got interrupted in the wrong moment, the removal of the pg_database row would also roll back, even though some irreversible steps have already been taken. E.g. DropDatabaseBuffers() might have thrown out dirty buffers, or files could have been unlinked. But we continued to allow connections to such a corrupted database. To fix this, mark databases invalid with an in-place update, just before starting to perform irreversible steps. As we can't add a new column in the back branches, we use pg_database.datconnlimit = -2 for this purpose. An invalid database cannot be connected to anymore, but can still be dropped. Unfortunately we can't easily add output to psql's \l to indicate that some database is invalid, it doesn't fit in any of the existing columns. Add tests verifying that a interrupted DROP DATABASE is handled correctly in the backend and in various tools. Reported-by: Evgeny Morozov <postgresql3@realityexists.net> Author: Andres Freund <andres@anarazel.de> Reviewed-by: Daniel Gustafsson <daniel@yesql.se> Reviewed-by: Thomas Munro <thomas.munro@gmail.com> Discussion: https://postgr.es/m/20230509004637.cgvmfwrbht7xm7p6@awork3.anarazel.de Discussion: https://postgr.es/m/20230314174521.74jl6ffqsee5mtug@awork3.anarazel.de Backpatch: 11-, bug present in all supported versions
2023-06-29Error message wording improvementsPeter Eisentraut
2023-06-07Remove read-only server settings lc_collate and lc_ctypePeter Eisentraut
The GUC settings lc_collate and lc_ctype are from a time when those locale settings were cluster-global. When those locale settings were made per-database (PG 8.4), the settings were kept as read-only. As of PG 15, you can use ICU as the per-database locale provider, so examining these settings is already less meaningful and possibly confusing, since you need to look into pg_database to find out what is really happening, and they would likely become fully obsolete in the future anyway. Reviewed-by: Jeff Davis <pgsql@j-davis.com> Discussion: https://www.postgresql.org/message-id/696054d1-bc88-b6ab-129a-18b8bce6a6f0@enterprisedb.com
2023-05-21Expand some more uses of "deleg" to "delegation" or "delegated".Tom Lane
Complete the task begun in 9c0a0e2ed: we don't want to use the abbreviation "deleg" for GSS delegation in any user-visible places. (For consistency, this also changes most internal uses too.) Abhijit Menon-Sen and Tom Lane Discussion: https://postgr.es/m/949048.1684639317@sss.pgh.pa.us
2023-05-20rename "gss_accept_deleg" to "gss_accept_delegation".Bruce Momjian
This is more consistent with existing GUC spelling. Discussion: https://postgr.es/m/ZGdnEsGtNj7+fZoa@momjian.us
2023-05-19Pre-beta mechanical code beautification.Tom Lane
Run pgindent, pgperltidy, and reformat-dat-files. This set of diffs is a bit larger than typical. We've updated to pg_bsd_indent 2.1.2, which properly indents variable declarations that have multi-line initialization expressions (the continuation lines are now indented one tab stop). We've also updated to perltidy version 20230309 and changed some of its settings, which reduces its desire to add whitespace to lines to make assignments etc. line up. Going forward, that should make for fewer random-seeming changes to existing code. Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
2023-04-20Remove obsolete defense against strxfrm() bugs.Thomas Munro
Old versions of Solaris and illumos had buffer overrun bugs in their strxfrm() implementations. The bugs were fixed more than a decade ago and the relevant releases are long out of vendor support. It's time to remove the defense added by commit be8b06c3. Reviewed-by: Nathan Bossart <nathandbossart@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CA+hUKGJ-ZPJwKHVLbqye92-ZXeLoCHu5wJL6L6HhNP7FkJ=meA@mail.gmail.com
2023-04-13De-Revert "Add support for Kerberos credential delegation"Stephen Frost
This reverts commit 3d03b24c3 (Revert Add support for Kerberos credential delegation) which was committed on the grounds of concern about portability, but on further review and discussion, it's clear that we are better off explicitly requiring MIT Kerberos as that appears to be the only GSSAPI library currently that's under proper maintenance and ongoing development. The API used for storing credentials was added to MIT Kerberos over a decade ago while for the other libraries which appear to be mainly based on Heimdal, which exists explicitly to be a re-implementation of MIT Kerberos, the API never made it to a released version (even though it was added to the Heimdal git repo over 5 years ago..). This post-feature-freeze change was approved by the RMT. Discussion: https://postgr.es/m/ZDDO6jaESKaBgej0%40tamriel.snowman.net
2023-04-08Revert "Add support for Kerberos credential delegation"Stephen Frost
This reverts commit 3d4fa227bce4294ce1cc214b4a9d3b7caa3f0454. Per discussion and buildfarm, this depends on APIs that seem to not be available on at least one platform (NetBSD). Should be certainly possible to rework to be optional on that platform if necessary but bit late for that at this point. Discussion: https://postgr.es/m/3286097.1680922218@sss.pgh.pa.us
2023-04-07Add support for Kerberos credential delegationStephen Frost
Support GSSAPI/Kerberos credentials being delegated to the server by a client. With this, a user authenticating to PostgreSQL using Kerberos (GSSAPI) credentials can choose to delegate their credentials to the PostgreSQL server (which can choose to accept them, or not), allowing the server to then use those delegated credentials to connect to another service, such as with postgres_fdw or dblink or theoretically any other service which is able to be authenticated using Kerberos. Both postgres_fdw and dblink are changed to allow non-superuser password-less connections but only when GSSAPI credentials have been delegated to the server by the client and GSSAPI is used to authenticate to the remote system. Authors: Stephen Frost, Peifeng Qiu Reviewed-By: David Christensen Discussion: https://postgr.es/m/CO1PR05MB8023CC2CB575E0FAAD7DF4F8A8E29@CO1PR05MB8023.namprd05.prod.outlook.com
2023-04-07Add VACUUM/ANALYZE BUFFER_USAGE_LIMIT optionDavid Rowley
Add new options to the VACUUM and ANALYZE commands called BUFFER_USAGE_LIMIT to allow users more control over how large to make the buffer access strategy that is used to limit the usage of buffers in shared buffers. Larger rings can allow VACUUM to run more quickly but have the drawback of VACUUM possibly evicting more buffers from shared buffers that might be useful for other queries running on the database. Here we also add a new GUC named vacuum_buffer_usage_limit which controls how large to make the access strategy when it's not specified in the VACUUM/ANALYZE command. This defaults to 256KB, which is the same size as the access strategy was prior to this change. This setting also controls how large to make the buffer access strategy for autovacuum. Per idea by Andres Freund. Author: Melanie Plageman Reviewed-by: David Rowley Reviewed-by: Andres Freund Reviewed-by: Justin Pryzby Reviewed-by: Bharath Rupireddy Discussion: https://postgr.es/m/20230111182720.ejifsclfwymw2reb@awork3.anarazel.de
2023-04-05Fix wrong word in comment.Robert Haas
Reported by Peter Smith. Discussion: http://postgr.es/m/CAHut+Pt52ueOEAO-G5qeZiiPv1p9pBT_W5Vj3BTYfC8sD8LFxw@mail.gmail.com
2023-04-04Perform logical replication actions as the table owner.Robert Haas
Up until now, logical replication actions have been performed as the subscription owner, who will generally be a superuser. Commit cec57b1a0fbcd3833086ba686897c5883e0a2afc documented hazards associated with that situation, namely, that any user who owns a table on the subscriber side could assume the privileges of the subscription owner by attaching a trigger, expression index, or some other kind of executable code to it. As a remedy, it suggested not creating configurations where users who are not fully trusted own tables on the subscriber. Although that will work, it basically precludes using logical replication in the way that people typically want to use it, namely, to replicate a database from one node to another without necessarily having any restrictions on which database users can own tables. So, instead, change logical replication to execute INSERT, UPDATE, DELETE, and TRUNCATE operations as the table owner when they are replicated. Since this involves switching the active user frequently within a session that is authenticated as the subscription user, also impose SECURITY_RESTRICTED_OPERATION restrictions on logical replication code. As an exception, if the table owner can SET ROLE to the subscription owner, these restrictions have no security value, so don't impose them in that case. Subscription owners are now required to have the ability to SET ROLE to every role that owns a table that the subscription is replicating. If they don't, replication will fail. Superusers, who normally own subscriptions, satisfy this property by default. Non-superusers users who own subscriptions will need to be granted the roles that own relevant tables. Patch by me, reviewed (but not necessarily in its entirety) by Jelte Fennema, Jeff Davis, and Noah Misch. Discussion: http://postgr.es/m/CA+TgmoaSCkg9ww9oppPqqs+9RVqCexYCE6Aq=UsYPfnOoDeFkw@mail.gmail.com
2023-03-25Add SysCacheGetAttrNotNull for guaranteed not-null attrsDaniel Gustafsson
When extracting an attr from a cached tuple in the syscache with SysCacheGetAttr the isnull parameter must be checked in case the attr cannot be NULL. For cases when this is known beforehand, a wrapper is introduced which perform the errorhandling internally on behalf of the caller, invoking an elog in case of a NULL attr. Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: David Rowley <dgrowleyml@gmail.com> Discussion: https://postgr.es/m/AD76405E-DB45-46B6-941F-17B1EB3A9076@yesql.se
2023-03-17Fix t_isspace(), etc., when datlocprovider=i and datctype=C.Jeff Davis
Check whether the datctype is C to determine whether t_isspace() and related functions use isspace() or iswspace(). Previously, t_isspace() checked whether the database default collation was C; which is incorrect when the default collation uses the ICU provider. Discussion: https://postgr.es/m/79e4354d9eccfdb00483146a6b9f6295202e7890.camel@j-davis.com Reviewed-by: Peter Eisentraut Backpatch-through: 15
2023-03-17Improve several permission-related error messages.Peter Eisentraut
Mainly move some detail from errmsg to errdetail, remove explicit mention of superuser where appropriate, since that is implied in most permission checks, and make messages more uniform. Author: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://www.postgresql.org/message-id/20230316234701.GA903298@nathanxps13
2023-03-16Integrate superuser check into has_rolreplication()Peter Eisentraut
This makes it consistent with similar functions like has_createrole_privilege() and allows removing some explicit superuser checks. Author: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://www.postgresql.org/message-id/20230310000313.GA3992372%40nathanxps13
2023-03-08Allow tailoring of ICU locales with custom rulesPeter Eisentraut
This exposes the ICU facility to add custom collation rules to a standard collation. New options are added to CREATE COLLATION, CREATE DATABASE, createdb, and initdb to set the rules. Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at> Reviewed-by: Daniel Verite <daniel@manitou-mail.org> Discussion: https://www.postgresql.org/message-id/flat/821c71a4-6ef0-d366-9acf-bb8e367f739f@enterprisedb.com
2023-03-03Don't leak descriptors into subprograms.Thomas Munro
Open long-lived data and WAL file descriptors with O_CLOEXEC. This flag was introduced by SUSv4 (POSIX.1-2008), and by now all of our target Unix systems have it. Our open() implementation for Windows already had that behavior, so provide a dummy O_CLOEXEC flag on that platform. For now, callers of open() and the "thin" wrappers in fd.c that deal in raw descriptors need to pass in O_CLOEXEC explicitly if desired. This commit does that for WAL files, and automatically for everything accessed via VFDs including SMgrRelation and BufFile. (With more discussion we might decide to turn it on automatically for the thin open()-wrappers too to avoid risk of missing places that need it, but these are typically used for short-lived descriptors where we don't expect to fork/exec, and it's remotely possible that extensions could be using these APIs and passing descriptors to subprograms deliberately, so that hasn't been done here.) Do the same for sockets and the postmaster pipe with FD_CLOEXEC. (Later commits might use modern interfaces to remove these extra fcntl() calls and more where possible, but we'll need them as a fallback for a couple of systems, so do it that way in this initial commit.) With this change, subprograms executed for archiving, copying etc will no longer have access to the server's descriptors, other than the ones that we decide to pass down. Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version) Discussion: https://postgr.es/m/CA%2BhUKGKb6FsAdQWcRL35KJsftv%2B9zXqQbzwkfRf1i0J2e57%2BhQ%40mail.gmail.com
2023-02-03Retire PG_SETMASK() macro.Thomas Munro
In the 90s we needed to deal with computers that still had the pre-standard signal masking APIs. That hasn't been relevant for a very long time on Unix systems, and c94ae9d8 got rid of a remaining dependency in our Windows porting code. PG_SETMASK didn't expose save/restore functionality, so we'd already started using sigprocmask() directly in places, creating the visual distraction of having two ways to spell it. It's not part of the API that extensions are expected to be using (but if they are, the change will be trivial). It seems like a good time to drop the old macro and just call the standard POSIX function. Reviewed-by: Nathan Bossart <nathandbossart@gmail.com> Discussion: https://postgr.es/m/CA%2BhUKG%2BKfQgrhHP2DLTohX1WwubaCBHmTzGnAEDPZ-Gug-Xskg%40mail.gmail.com