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openGauss-server/src/include/utils/memutils.h
2021-06-02 20:55:13 +08:00

198 lines
7.6 KiB
C++

/* -------------------------------------------------------------------------
*
* memutils.h
* This file contains declarations for memory allocation utility
* functions. These are functions that are not quite widely used
* enough to justify going in utils/palloc.h, but are still part
* of the API of the memory management subsystem.
*
*
* Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* src/include/utils/memutils.h
*
* -------------------------------------------------------------------------
*/
#ifndef MEMUTILS_H
#define MEMUTILS_H
#include "nodes/memnodes.h"
#include "pgtime.h"
#include "storage/proc.h"
enum MemoryContextType {
STANDARD_CONTEXT, // postgres orignal context
STACK_CONTEXT, // a simple context, do not support free single pointer
SHARED_CONTEXT, // shared context used by different threads
MEMALIGN_CONTEXT, // the context only used to allocate the aligned memory
MEMALIGN_SHRCTX, // the shared context only used to allocate the aligned memory
};
/*
* MaxAllocSize
* Quasi-arbitrary limit on size of allocations.
*
* Note:
* There is no guarantee that allocations smaller than MaxAllocSize
* will succeed. Allocation requests larger than MaxAllocSize will
* be summarily denied.
*
* XXX This is deliberately chosen to correspond to the limiting size
* of varlena objects under TOAST. See VARSIZE_4B() and related macros
* in postgres.h. Many datatypes assume that any allocatable size can
* be represented in a varlena header.
*
* XXX Also, various places in aset.c assume they can compute twice an
* allocation's size without overflow, so beware of raising this.
*/
#define MaxAllocSize ((Size)0x3fffffff) /* 1 gigabyte - 1 */
#define MaxBuildAllocSize ((Size)0x3ffffff) /* 64MB - 1 */
#define AllocSizeIsValid(size) ((Size)(size) <= MaxAllocSize)
#define MaxAllocHugeSize ((Size)-1 >> 1) /* SIZE_MAX / 2 */
#define AllocHugeSizeIsValid(size) ((Size)(size) <= MaxAllocHugeSize)
/*
* All chunks allocated by any memory context manager are required to be
* preceded by a StandardChunkHeader at a spacing of STANDARDCHUNKHEADERSIZE.
* A currently-allocated chunk must contain a backpointer to its owning
* context as well as the allocated size of the chunk. The backpointer is
* used by pfree() and repalloc() to find the context to call. The allocated
* size is not absolutely essential, but it's expected to be needed by any
* reasonable implementation.
*/
typedef struct StandardChunkHeader {
MemoryContext context; /* owning context */
Size size; /* size of data space allocated in chunk */
#ifdef MEMORY_CONTEXT_CHECKING
/* when debugging memory usage, also store actual requested size */
Size requested_size;
const char* file;
int line;
#endif
} StandardChunkHeader;
#define STANDARDCHUNKHEADERSIZE MAXALIGN(sizeof(StandardChunkHeader))
// Process wise memory context
//
extern MemoryContext AdioSharedContext;
extern MemoryContext ProcSubXidCacheContext;
extern MemoryContext PmTopMemoryContext;
extern MemoryContext StreamInfoContext;
extern THR_LOCAL PGDLLIMPORT MemoryContext ErrorContext;
/*
* Memory-context-type-independent functions in mcxt.c
*/
extern void MemoryContextInit(void);
extern void MemoryContextReset(MemoryContext context);
extern void MemoryContextDelete(MemoryContext context);
extern void MemoryContextResetChildren(MemoryContext context);
extern void MemoryContextDeleteChildren(MemoryContext context, List* context_list = NULL);
extern void MemoryContextDestroyAtThreadExit(MemoryContext context);
extern void MemoryContextResetAndDeleteChildren(MemoryContext context);
extern void MemoryContextSetParent(MemoryContext context, MemoryContext new_parent);
extern Size GetMemoryChunkSpace(void* pointer);
extern MemoryContext GetMemoryChunkContext(void* pointer);
extern MemoryContext MemoryContextGetParent(MemoryContext context);
extern bool MemoryContextIsEmpty(MemoryContext context);
extern void MemoryContextStats(MemoryContext context);
extern void MemoryContextSeal(MemoryContext context);
extern void MemoryContextUnSeal(MemoryContext context);
extern void MemoryContextUnSealChildren(MemoryContext context);
#ifdef MEMORY_CONTEXT_CHECKING
extern void MemoryContextCheck(MemoryContext context, bool own_by_session);
#define MemoryContextCheck2(mctx)
#endif
extern bool MemoryContextContains(MemoryContext context, void* pointer);
extern MemoryContext MemoryContextOriginal(const char* node);
/*
* This routine handles the context-type-independent part of memory
* context creation. It's intended to be called from context-type-
* specific creation routines, and noplace else.
*/
extern MemoryContext MemoryContextCreate(
NodeTag tag, Size size, MemoryContext parent, const char* name, const char* file, int line);
/* Interface for PosgGIS and has the same structure with PG's MemoryContextCreate*/
extern MemoryContext MemoryContextCreate(
NodeTag tag, Size size, MemoryContextMethods* methods, MemoryContext parent, const char* name);
/*
* Memory-context-type-specific functions
*/
#define DEFAULT_MEMORY_CONTEXT_MAX_SIZE 0 /* 0 MB as default value for AllocSetContextCreat function */
#define SHARED_MEMORY_CONTEXT_MAX_SIZE (100 * 1024 * 1024) /* 100 MB */
/* aset.c */
extern MemoryContext AllocSetContextCreate(MemoryContext parent, const char* name, Size minContextSize,
Size initBlockSize, Size maxBlockSize, MemoryContextType type = STANDARD_CONTEXT,
Size maxSize = DEFAULT_MEMORY_CONTEXT_MAX_SIZE, bool isSession = false);
/*
* Recommended default alloc parameters, suitable for "ordinary" contexts
* that might hold quite a lot of data.
*/
#define ALLOCSET_DEFAULT_MINSIZE 0
#define ALLOCSET_DEFAULT_INITSIZE (8 * 1024)
#define ALLOCSET_DEFAULT_MAXSIZE (8 * 1024 * 1024)
#define ALLOCSET_DEFAULT_SIZES ALLOCSET_DEFAULT_MINSIZE, ALLOCSET_DEFAULT_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE
/*
* Recommended alloc parameters for "small" contexts that are not expected
* to contain much data (for example, a context to contain a query plan).
*/
#define ALLOCSET_SMALL_MINSIZE 0
#define ALLOCSET_SMALL_INITSIZE (1 * 1024)
#define ALLOCSET_SMALL_MAXSIZE (8 * 1024)
/* default grow ratio for sort and materialize when it spreads */
#define DEFAULT_GROW_RATIO 2.0
/* default auto spread min ratio, and memory spread under this ratio is abondaned */
#define MEM_AUTO_SPREAD_MIN_RATIO 0.1
// AutoContextSwitch
// Auto object for memoryContext switch
//
class AutoContextSwitch {
public:
AutoContextSwitch(MemoryContext memContext)
{
if (memContext == NULL) {
m_oldMemContext = CurrentMemoryContext;
} else {
m_oldMemContext = MemoryContextSwitchTo(memContext);
}
};
~AutoContextSwitch()
{
MemoryContextSwitchTo(m_oldMemContext);
}
private:
MemoryContext m_oldMemContext;
};
/* In case we haven't init u_sess->when we try to create memory context and alloc memory */
#define IS_USESS_AVAILABLE (likely(u_sess != NULL))
#define GS_MP_INITED (t_thrd.utils_cxt.gs_mp_inited)
#define MEMORY_TRACKING_MODE (IS_USESS_AVAILABLE ? u_sess->attr.attr_memory.memory_tracking_mode : 0)
#define MEMORY_TRACKING_QUERY_PEAK (IS_USESS_AVAILABLE ? (u_sess->attr.attr_memory.memory_tracking_mode == MEMORY_TRACKING_PEAKMEMORY ) : 0)
#define ENABLE_MEMORY_CONTEXT_CONTROL \
(IS_USESS_AVAILABLE ? u_sess->attr.attr_memory.enable_memory_context_control : false)
#define MEMORY_FAULT_PERCENT (IS_USESS_AVAILABLE ? u_sess->attr.attr_resource.memory_fault_percent : 0)
#define STATEMENT_MAX_MEM (IS_USESS_AVAILABLE ? u_sess->attr.attr_sql.statement_max_mem : 0)
#endif /* MEMUTILS_H */