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/*------------------------------------------------------------------------
* 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) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/pg_config_manual.h
*------------------------------------------------------------------------
*/
/*
* Maximum length for identifiers (e.g. table names, column names,
* function names). Names actually are limited to one less byte than this,
* because the length must include a trailing zero byte.
*
* Changing this requires an initdb.
*/
#define NAMEDATALEN 64
/*
* 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).
*/
#define FUNC_MAX_ARGS 100
/*
* 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.
*/
#define INDEX_MAX_KEYS 32
/*
* Set the upper and lower bounds of sequence values.
*/
#define SEQ_MAXVALUE INT64CONST(0x7FFFFFFFFFFFFFFF)
#define SEQ_MINVALUE (-SEQ_MAXVALUE)
/*
* Number of spare LWLocks to allocate for user-defined add-on code.
*/
#define NUM_USER_DEFINED_LWLOCKS 4
/*
* 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.
*/
#define NUM_SPINLOCK_SEMAPHORES 128
/*
* Define this if you want to allow the lo_import and lo_export SQL
* functions to be executed by ordinary users. By default these
* functions are only available to the Postgres superuser. CAUTION:
* These functions are SECURITY HOLES since they can read and write
* any file that the PostgreSQL server has permission to access. If
* you turn this on, don't say we didn't warn you.
*/
/* #define ALLOW_DANGEROUS_LO_FUNCTIONS */
/*
* 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.
*/
#define MAXPGPATH 1024
/*
* PG_SOMAXCONN: maximum accept-queue length limit passed to
* listen(2). You'd think we should use SOMAXCONN from
* <sys/socket.h>, but on many systems that symbol is much smaller
* than the kernel's actual limit. In any case, this symbol need be
* twiddled only if you have a kernel that refuses large limit values,
* rather than silently reducing the value to what it can handle
* (which is what most if not all Unixen do).
*/
#define PG_SOMAXCONN 10000
/*
* You can try changing this if you have a machine with bytes of
* another size, but no guarantee...
*/
#define BITS_PER_BYTE 8
/*
* 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.
*/
#define ALIGNOF_BUFFER 32
/*
* Disable UNIX sockets for certain operating systems.
*/
#if defined(WIN32)
#undef HAVE_UNIX_SOCKETS
#endif
/*
* Define this if your operating system supports link()
*/
#if !defined(WIN32) && !defined(__CYGWIN__)
#define HAVE_WORKING_LINK 1
#endif
/*
* 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.
*/
#if HAVE_DECL_POSIX_FADVISE && defined(HAVE_POSIX_FADVISE)
#define USE_POSIX_FADVISE
#endif
/*
* 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.)
*/
#ifdef USE_POSIX_FADVISE
#define USE_PREFETCH
#endif
/*
* 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.
*/
#define DEFAULT_PGSOCKET_DIR "/var/run/postgresql"
/*
* The random() function is expected to yield values between 0 and
* MAX_RANDOM_VALUE. Currently, all known implementations yield
* 0..2^31-1, so we just hardwire this constant. We could do a
* configure test if it proves to be necessary. CAUTION: Think not to
* replace this with RAND_MAX. RAND_MAX defines the maximum value of
* the older rand() function, which is often different from --- and
* considerably inferior to --- random().
*/
#define MAX_RANDOM_VALUE (0x7FFFFFFF)
/*
* Set the format style used by gcc to check printf type functions. We really
* want the "gnu_printf" style set, which includes what glibc uses, such
* as %m for error strings and %lld for 64 bit long longs. But not all gcc
* compilers are known to support it, so we just use "printf" which all
* gcc versions alive are known to support, except on Windows where
* using "gnu_printf" style makes a dramatic difference. Maybe someday
* we'll have a configure test for this, if we ever discover use of more
* variants to be necessary.
*/
#ifdef WIN32
#define PG_PRINTF_ATTRIBUTE gnu_printf
#else
#define PG_PRINTF_ATTRIBUTE printf
#endif
/*
* On PPC machines, decide whether to use the mutex hint bit in LWARX
* instructions. Setting the hint bit will slightly improve spinlock
* performance on POWER6 and later machines, but does nothing before that,
* and will result in illegal-instruction failures on some pre-POWER4
* machines. By default we use the hint bit when building for 64-bit PPC,
* which should be safe in nearly all cases. You might want to override
* this if you are building 32-bit code for a known-recent PPC machine.
*/
#ifdef HAVE_PPC_LWARX_MUTEX_HINT /* must have assembler support in any case */
#if defined(__ppc64__) || defined(__powerpc64__)
#define USE_PPC_LWARX_MUTEX_HINT
#endif
#endif
/*
* On PPC machines, decide whether to use LWSYNC instructions in place of
* ISYNC and SYNC. This provides slightly better performance, but will
* result in illegal-instruction failures on some pre-POWER4 machines.
* By default we use LWSYNC when building for 64-bit PPC, which should be
* safe in nearly all cases.
*/
#if defined(__ppc64__) || defined(__powerpc64__)
#define USE_PPC_LWSYNC
#endif
/*
*------------------------------------------------------------------------
* The following symbols are for enabling debugging code, not for
* controlling user-visible features or resource limits.
*------------------------------------------------------------------------
*/
/*
* 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.
*/
#ifdef USE_ASSERT_CHECKING
#define CLOBBER_FREED_MEMORY
#endif
/*
* Define this to check memory allocation errors (scribbling on more
* bytes than were allocated). Right now, this gets defined
* automatically if --enable-cassert.
*/
#ifdef USE_ASSERT_CHECKING
#define MEMORY_CONTEXT_CHECKING
#endif
/*
* 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 */
/*
* 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 */
/*
* 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.
*/
#define TRACE_SORT 1
/*
* Enable tracing of syncscan operations (see also the trace_syncscan GUC var).
*/
/* #define TRACE_SYNCSCAN */
/*
* Other debug #defines (documentation, anyone?)
*/
/* #define HEAPDEBUGALL */
/* #define ACLDEBUG */
/* #define RTDEBUG */