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/*------------------------------------------------------------------------
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* PostgreSQL manual configuration settings
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* This file contains various configuration symbols and limits. In
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* all cases, changing them is only useful in very rare situations or
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* for developers. If you edit any of these, be sure to do a *full*
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* rebuild (and an initdb if noted).
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* Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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* src/include/pg_config_manual.h
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*------------------------------------------------------------------------
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* Maximum length for identifiers (e.g. table names, column names,
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* function names). Names actually are limited to one less byte than this,
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* because the length must include a trailing zero byte.
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* Changing this requires an initdb.
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#define NAMEDATALEN 64
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* Maximum number of arguments to a function.
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* The minimum value is 8 (GIN indexes use 8-argument support functions).
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* The maximum possible value is around 600 (limited by index tuple size in
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* pg_proc's index; BLCKSZ larger than 8K would allow more). Values larger
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* than needed will waste memory and processing time, but do not directly
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* Changing this does not require an initdb, but it does require a full
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* backend recompile (including any user-defined C functions).
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#define FUNC_MAX_ARGS 100
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* Maximum number of columns in an index. There is little point in making
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* this anything but a multiple of 32, because the main cost is associated
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* with index tuple header size (see access/itup.h).
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* Changing this requires an initdb.
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#define INDEX_MAX_KEYS 32
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* Set the upper and lower bounds of sequence values.
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#define SEQ_MAXVALUE INT64CONST(0x7FFFFFFFFFFFFFFF)
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#define SEQ_MINVALUE (-SEQ_MAXVALUE)
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* Number of spare LWLocks to allocate for user-defined add-on code.
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#define NUM_USER_DEFINED_LWLOCKS 4
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* Define this if you want to allow the lo_import and lo_export SQL
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* functions to be executed by ordinary users. By default these
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* functions are only available to the Postgres superuser. CAUTION:
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* These functions are SECURITY HOLES since they can read and write
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* any file that the PostgreSQL server has permission to access. If
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* you turn this on, don't say we didn't warn you.
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/* #define ALLOW_DANGEROUS_LO_FUNCTIONS */
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* MAXPGPATH: standard size of a pathname buffer in PostgreSQL (hence,
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* maximum usable pathname length is one less).
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* We'd use a standard system header symbol for this, if there weren't
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* so many to choose from: MAXPATHLEN, MAX_PATH, PATH_MAX are all
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* defined by different "standards", and often have different values
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* on the same platform! So we just punt and use a reasonably
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* generous setting here.
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#define MAXPGPATH 1024
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* PG_SOMAXCONN: maximum accept-queue length limit passed to
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* listen(2). You'd think we should use SOMAXCONN from
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* <sys/socket.h>, but on many systems that symbol is much smaller
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* than the kernel's actual limit. In any case, this symbol need be
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* twiddled only if you have a kernel that refuses large limit values,
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* rather than silently reducing the value to what it can handle
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* (which is what most if not all Unixen do).
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#define PG_SOMAXCONN 10000
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* You can try changing this if you have a machine with bytes of
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* another size, but no guarantee...
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#define BITS_PER_BYTE 8
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* Preferred alignment for disk I/O buffers. On some CPUs, copies between
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* user space and kernel space are significantly faster if the user buffer
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* is aligned on a larger-than-MAXALIGN boundary. Ideally this should be
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* a platform-dependent value, but for now we just hard-wire it.
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#define ALIGNOF_BUFFER 32
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* Disable UNIX sockets for certain operating systems.
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#undef HAVE_UNIX_SOCKETS
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* Define this if your operating system supports link()
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#if !defined(WIN32) && !defined(__CYGWIN__)
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#define HAVE_WORKING_LINK 1
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* USE_POSIX_FADVISE controls whether Postgres will attempt to use the
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* posix_fadvise() kernel call. Usually the automatic configure tests are
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* sufficient, but some older Linux distributions had broken versions of
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* posix_fadvise(). If necessary you can remove the #define here.
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#if HAVE_DECL_POSIX_FADVISE && defined(HAVE_POSIX_FADVISE)
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#define USE_POSIX_FADVISE
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* USE_PREFETCH code should be compiled only if we have a way to implement
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* prefetching. (This is decoupled from USE_POSIX_FADVISE because there
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* might in future be support for alternative low-level prefetch APIs.)
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#ifdef USE_POSIX_FADVISE
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* This is the default directory in which AF_UNIX socket files are
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* placed. Caution: changing this risks breaking your existing client
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* applications, which are likely to continue to look in the old
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* directory. But if you just hate the idea of sockets in /tmp,
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* here's where to twiddle it. You can also override this at runtime
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* with the postmaster's -k switch.
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#define DEFAULT_PGSOCKET_DIR "/tmp"
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* The random() function is expected to yield values between 0 and
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* MAX_RANDOM_VALUE. Currently, all known implementations yield
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* 0..2^31-1, so we just hardwire this constant. We could do a
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* configure test if it proves to be necessary. CAUTION: Think not to
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* replace this with RAND_MAX. RAND_MAX defines the maximum value of
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* the older rand() function, which is often different from --- and
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* considerably inferior to --- random().
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#define MAX_RANDOM_VALUE (0x7FFFFFFF)
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* Set the format style used by gcc to check printf type functions. We really
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* want the "gnu_printf" style set, which includes what glibc uses, such
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* as %m for error strings and %lld for 64 bit long longs. But not all gcc
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* compilers are known to support it, so we just use "printf" which all
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* gcc versions alive are known to support, except on Windows where
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* using "gnu_printf" style makes a dramatic difference. Maybe someday
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* we'll have a configure test for this, if we ever discover use of more
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* variants to be necessary.
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#define PG_PRINTF_ATTRIBUTE gnu_printf
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#define PG_PRINTF_ATTRIBUTE printf
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* On PPC machines, decide whether to use the mutex hint bit in LWARX
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* instructions. Setting the hint bit will slightly improve spinlock
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* performance on POWER6 and later machines, but does nothing before that,
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* and will result in illegal-instruction failures on some pre-POWER4
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* machines. By default we use the hint bit when building for 64-bit PPC,
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* which should be safe in nearly all cases. You might want to override
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* this if you are building 32-bit code for a known-recent PPC machine.
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#ifdef HAVE_PPC_LWARX_MUTEX_HINT /* must have assembler support in any case */
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#if defined(__ppc64__) || defined(__powerpc64__)
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#define USE_PPC_LWARX_MUTEX_HINT
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* On PPC machines, decide whether to use LWSYNC instructions in place of
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* ISYNC and SYNC. This provides slightly better performance, but will
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* result in illegal-instruction failures on some pre-POWER4 machines.
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* By default we use LWSYNC when building for 64-bit PPC, which should be
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* safe in nearly all cases.
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#if defined(__ppc64__) || defined(__powerpc64__)
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#define USE_PPC_LWSYNC
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*------------------------------------------------------------------------
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* The following symbols are for enabling debugging code, not for
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* controlling user-visible features or resource limits.
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*------------------------------------------------------------------------
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* Define this to cause pfree()'d memory to be cleared immediately, to
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* facilitate catching bugs that refer to already-freed values.
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* Right now, this gets defined automatically if --enable-cassert.
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#ifdef USE_ASSERT_CHECKING
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#define CLOBBER_FREED_MEMORY
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* Define this to check memory allocation errors (scribbling on more
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* bytes than were allocated). Right now, this gets defined
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* automatically if --enable-cassert.
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#ifdef USE_ASSERT_CHECKING
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#define MEMORY_CONTEXT_CHECKING
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* Define this to cause palloc()'d memory to be filled with random data, to
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* facilitate catching code that depends on the contents of uninitialized
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* memory. Caution: this is horrendously expensive.
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/* #define RANDOMIZE_ALLOCATED_MEMORY */
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* Define this to force all parse and plan trees to be passed through
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* copyObject(), to facilitate catching errors and omissions in
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/* #define COPY_PARSE_PLAN_TREES */
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* Enable debugging print statements for lock-related operations.
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/* #define LOCK_DEBUG */
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* Enable debugging print statements for WAL-related operations; see
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* also the wal_debug GUC var.
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/* #define WAL_DEBUG */
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* Enable tracing of resource consumption during sort operations;
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* see also the trace_sort GUC var. For 8.1 this is enabled by default.
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* Enable tracing of syncscan operations (see also the trace_syncscan GUC var).
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/* #define TRACE_SYNCSCAN */
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* Other debug #defines (documentation, anyone?)
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/* #define HEAPDEBUGALL */
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/* #define ACLDEBUG */
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/* #define RTDEBUG */