| /*------------------------------------------------------------------------ | |
| * PostgreSQL manual configuration settings | |
| * | |
| * This file contains various configuration symbols and limits. In | |
| * all cases, changing them is only useful in very rare situations or | |
| * for developers. If you edit any of these, be sure to do a *full* | |
| * rebuild (and an initdb if noted). | |
| * | |
| * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group | |
| * Portions Copyright (c) 1994, Regents of the University of California | |
| * | |
| * src/include/pg_config_manual.h | |
| *------------------------------------------------------------------------ | |
| */ | |
| /* | |
| * This is the default value for wal_segment_size to be used when initdb is run | |
| * without the --wal-segsize option. It must be a valid segment size. | |
| */ | |
| /* | |
| * Maximum length for identifiers (e.g. table names, column names, | |
| * function names). Names actually are limited to one fewer byte than this, | |
| * because the length must include a trailing zero byte. | |
| * | |
| * Changing this requires an initdb. | |
| */ | |
| /* | |
| * Maximum number of arguments to a function. | |
| * | |
| * The minimum value is 8 (GIN indexes use 8-argument support functions). | |
| * The maximum possible value is around 600 (limited by index tuple size in | |
| * pg_proc's index; BLCKSZ larger than 8K would allow more). Values larger | |
| * than needed will waste memory and processing time, but do not directly | |
| * cost disk space. | |
| * | |
| * Changing this does not require an initdb, but it does require a full | |
| * backend recompile (including any user-defined C functions). | |
| */ | |
| /* | |
| * When creating a product derived from PostgreSQL with changes that cause | |
| * incompatibilities for loadable modules, it is recommended to change this | |
| * string so that dfmgr.c can refuse to load incompatible modules with a clean | |
| * error message. Typical examples that cause incompatibilities are any | |
| * changes to node tags or node structures. (Note that dfmgr.c already | |
| * detects common sources of incompatibilities due to major version | |
| * differences and due to some changed compile-time constants. This setting | |
| * is for catching anything that cannot be detected in a straightforward way.) | |
| * | |
| * There is no prescribed format for the string. The suggestion is to include | |
| * product or company name, and optionally any internally-relevant ABI | |
| * version. Example: "ACME Postgres/1.2". Note that the string will appear | |
| * in a user-facing error message if an ABI mismatch is detected. | |
| */ | |
| /* | |
| * Maximum number of columns in an index. There is little point in making | |
| * this anything but a multiple of 32, because the main cost is associated | |
| * with index tuple header size (see access/itup.h). | |
| * | |
| * Changing this requires an initdb. | |
| */ | |
| /* | |
| * Maximum number of columns in a partition key | |
| */ | |
| /* | |
| * Decide whether built-in 8-byte types, including float8, int8, and | |
| * timestamp, are passed by value. This is on by default if sizeof(Datum) >= | |
| * 8 (that is, on 64-bit platforms). If sizeof(Datum) < 8 (32-bit platforms), | |
| * this must be off. We keep this here as an option so that it is easy to | |
| * test the pass-by-reference code paths on 64-bit platforms. | |
| * | |
| * Changing this requires an initdb. | |
| */ | |
| /* | |
| * When we don't have native spinlocks, we use semaphores to simulate them. | |
| * Decreasing this value reduces consumption of OS resources; increasing it | |
| * may improve performance, but supplying a real spinlock implementation is | |
| * probably far better. | |
| */ | |
| /* | |
| * When we have neither spinlocks nor atomic operations support we're | |
| * implementing atomic operations on top of spinlock on top of semaphores. To | |
| * be safe against atomic operations while holding a spinlock separate | |
| * semaphores have to be used. | |
| */ | |
| /* | |
| * MAXPGPATH: standard size of a pathname buffer in PostgreSQL (hence, | |
| * maximum usable pathname length is one less). | |
| * | |
| * We'd use a standard system header symbol for this, if there weren't | |
| * so many to choose from: MAXPATHLEN, MAX_PATH, PATH_MAX are all | |
| * defined by different "standards", and often have different values | |
| * on the same platform! So we just punt and use a reasonably | |
| * generous setting here. | |
| */ | |
| /* | |
| * You can try changing this if you have a machine with bytes of | |
| * another size, but no guarantee... | |
| */ | |
| /* | |
| * Preferred alignment for disk I/O buffers. On some CPUs, copies between | |
| * user space and kernel space are significantly faster if the user buffer | |
| * is aligned on a larger-than-MAXALIGN boundary. Ideally this should be | |
| * a platform-dependent value, but for now we just hard-wire it. | |
| */ | |
| /* | |
| * If EXEC_BACKEND is defined, the postmaster uses an alternative method for | |
| * starting subprocesses: Instead of simply using fork(), as is standard on | |
| * Unix platforms, it uses fork()+exec() or something equivalent on Windows, | |
| * as well as lots of extra code to bring the required global state to those | |
| * new processes. This must be enabled on Windows (because there is no | |
| * fork()). On other platforms, it's only useful for verifying those | |
| * otherwise Windows-specific code paths. | |
| */ | |
| /* | |
| * USE_POSIX_FADVISE controls whether Postgres will attempt to use the | |
| * posix_fadvise() kernel call. Usually the automatic configure tests are | |
| * sufficient, but some older Linux distributions had broken versions of | |
| * posix_fadvise(). If necessary you can remove the #define here. | |
| */ | |
| /* | |
| * USE_PREFETCH code should be compiled only if we have a way to implement | |
| * prefetching. (This is decoupled from USE_POSIX_FADVISE because there | |
| * might in future be support for alternative low-level prefetch APIs. | |
| * If you change this, you probably need to adjust the error message in | |
| * check_effective_io_concurrency.) | |
| */ | |
| /* | |
| * Default and maximum values for backend_flush_after, bgwriter_flush_after | |
| * and checkpoint_flush_after; measured in blocks. Currently, these are | |
| * enabled by default if sync_file_range() exists, ie, only on Linux. Perhaps | |
| * we could also enable by default if we have mmap and msync(MS_ASYNC)? | |
| */ | |
| /* upper limit for all three variables */ | |
| /* | |
| * USE_SSL code should be compiled only when compiling with an SSL | |
| * implementation. | |
| */ | |
| /* | |
| * This is the default directory in which AF_UNIX socket files are | |
| * placed. Caution: changing this risks breaking your existing client | |
| * applications, which are likely to continue to look in the old | |
| * directory. But if you just hate the idea of sockets in /tmp, | |
| * here's where to twiddle it. You can also override this at runtime | |
| * with the postmaster's -k switch. | |
| * | |
| * If set to an empty string, then AF_UNIX sockets are not used by default: A | |
| * server will not create an AF_UNIX socket unless the run-time configuration | |
| * is changed, a client will connect via TCP/IP by default and will only use | |
| * an AF_UNIX socket if one is explicitly specified. | |
| * | |
| * This is done by default on Windows because there is no good standard | |
| * location for AF_UNIX sockets and many installations on Windows don't | |
| * support them yet. | |
| */ | |
| /* | |
| * This is the default event source for Windows event log. | |
| */ | |
| /* | |
| * Assumed cache line size. This doesn't affect correctness, but can be used | |
| * for low-level optimizations. This is mostly used to pad various data | |
| * structures, to ensure that highly-contended fields are on different cache | |
| * lines. Too small a value can hurt performance due to false sharing, while | |
| * the only downside of too large a value is a few bytes of wasted memory. | |
| * The default is 128, which should be large enough for all supported | |
| * platforms. | |
| */ | |
| /* | |
| * Assumed alignment requirement for direct I/O. 4K corresponds to common | |
| * sector and memory page size. | |
| */ | |
| /* | |
| *------------------------------------------------------------------------ | |
| * The following symbols are for enabling debugging code, not for | |
| * controlling user-visible features or resource limits. | |
| *------------------------------------------------------------------------ | |
| */ | |
| /* | |
| * Force use of the non-recursive JSON parser in all cases. This is useful | |
| * to validate the working of the parser, and the regression tests should | |
| * pass except for some different error messages about the stack limit. | |
| */ | |
| /* #define FORCE_JSON_PSTACK */ | |
| /* | |
| * Include Valgrind "client requests", mostly in the memory allocator, so | |
| * Valgrind understands PostgreSQL memory contexts. This permits detecting | |
| * memory errors that Valgrind would not detect on a vanilla build. It also | |
| * enables detection of buffer accesses that take place without holding a | |
| * buffer pin (or without holding a buffer lock in the case of index access | |
| * methods that superimpose their own custom client requests on top of the | |
| * generic bufmgr.c requests). | |
| * | |
| * "make installcheck" is significantly slower under Valgrind. The client | |
| * requests fall in hot code paths, so USE_VALGRIND slows execution by a few | |
| * percentage points even when not run under Valgrind. | |
| * | |
| * Do not try to test the server under Valgrind without having built the | |
| * server with USE_VALGRIND; else you will get false positives from sinval | |
| * messaging (see comments in AddCatcacheInvalidationMessage). It's also | |
| * important to use the suppression file src/tools/valgrind.supp to | |
| * exclude other known false positives. | |
| * | |
| * You should normally use MEMORY_CONTEXT_CHECKING with USE_VALGRIND; | |
| * instrumentation of repalloc() is inferior without it. | |
| */ | |
| /* #define USE_VALGRIND */ | |
| /* | |
| * Define this to cause pfree()'d memory to be cleared immediately, to | |
| * facilitate catching bugs that refer to already-freed values. | |
| * Right now, this gets defined automatically if --enable-cassert. | |
| */ | |
| /* | |
| * Define this to check memory allocation errors (scribbling on more | |
| * bytes than were allocated). Right now, this gets defined | |
| * automatically if --enable-cassert or USE_VALGRIND. | |
| */ | |
| /* | |
| * Define this to cause palloc()'d memory to be filled with random data, to | |
| * facilitate catching code that depends on the contents of uninitialized | |
| * memory. Caution: this is horrendously expensive. | |
| */ | |
| /* #define RANDOMIZE_ALLOCATED_MEMORY */ | |
| /* | |
| * For cache-invalidation debugging, define DISCARD_CACHES_ENABLED to enable | |
| * use of the debug_discard_caches GUC to aggressively flush syscache/relcache | |
| * entries whenever it's possible to deliver invalidations. See | |
| * AcceptInvalidationMessages() in src/backend/utils/cache/inval.c for | |
| * details. | |
| * | |
| * USE_ASSERT_CHECKING builds default to enabling this. It's possible to use | |
| * DISCARD_CACHES_ENABLED without a cassert build and the implied | |
| * CLOBBER_FREED_MEMORY and MEMORY_CONTEXT_CHECKING options, but it's unlikely | |
| * to be as effective at identifying problems. | |
| */ | |
| /* #define DISCARD_CACHES_ENABLED */ | |
| /* | |
| * Backwards compatibility for the older compile-time-only clobber-cache | |
| * macros. | |
| */ | |
| /* | |
| * Recover memory used for relcache entries when invalidated. See | |
| * RelationBuildDesc() in src/backend/utils/cache/relcache.c. | |
| * | |
| * This is active automatically for clobber-cache builds when clobbering is | |
| * active, but can be overridden here by explicitly defining | |
| * RECOVER_RELATION_BUILD_MEMORY. Define to 1 to always free relation cache | |
| * memory even when clobber is off, or to 0 to never free relation cache | |
| * memory even when clobbering is on. | |
| */ | |
| /* #define RECOVER_RELATION_BUILD_MEMORY 0 */ /* Force disable */ | |
| /* #define RECOVER_RELATION_BUILD_MEMORY 1 */ /* Force enable */ | |
| /* | |
| * Define this to force all parse and plan trees to be passed through | |
| * copyObject(), to facilitate catching errors and omissions in | |
| * copyObject(). | |
| */ | |
| /* #define COPY_PARSE_PLAN_TREES */ | |
| /* | |
| * Define this to force Bitmapset reallocation on each modification. Helps | |
| * to find dangling pointers to Bitmapset's. | |
| */ | |
| /* #define REALLOCATE_BITMAPSETS */ | |
| /* | |
| * Define this to force all parse and plan trees to be passed through | |
| * outfuncs.c/readfuncs.c, to facilitate catching errors and omissions in | |
| * those modules. | |
| */ | |
| /* #define WRITE_READ_PARSE_PLAN_TREES */ | |
| /* | |
| * Define this to force all raw parse trees for DML statements to be scanned | |
| * by raw_expression_tree_walker(), to facilitate catching errors and | |
| * omissions in that function. | |
| */ | |
| /* #define RAW_EXPRESSION_COVERAGE_TEST */ | |
| /* | |
| * Enable debugging print statements for lock-related operations. | |
| */ | |
| /* #define LOCK_DEBUG */ | |
| /* | |
| * Enable debugging print statements for WAL-related operations; see | |
| * also the wal_debug GUC var. | |
| */ | |
| /* #define WAL_DEBUG */ | |
| /* | |
| * Enable tracing of resource consumption during sort operations; | |
| * see also the trace_sort GUC var. For 8.1 this is enabled by default. | |
| */ | |
| /* | |
| * Enable tracing of syncscan operations (see also the trace_syncscan GUC var). | |
| */ | |
| /* #define TRACE_SYNCSCAN */ | |