buf_init.c File Reference

#include "postgres.h"
#include "storage/aio.h"
#include "storage/buf_internals.h"
#include "storage/bufmgr.h"
#include "storage/proclist.h"
#include "storage/shmem.h"
#include "storage/subsystems.h"

Include dependency graph for buf_init.c:

Go to the source code of this file.

Functions
static void	BufferManagerShmemRequest (void *arg)
static void	BufferManagerShmemInit (void *arg)
static void	BufferManagerShmemAttach (void *arg)

Variables
BufferDescPadded *	BufferDescriptors
char *	BufferBlocks
ConditionVariableMinimallyPadded *	BufferIOCVArray
WritebackContext	BackendWritebackContext
CkptSortItem *	CkptBufferIds
const ShmemCallbacks	BufferManagerShmemCallbacks

Function Documentation

BufferManagerShmemAttach()

static void BufferManagerShmemAttach ( void *  arg )

static

Definition at line 148 of file buf_init.c.

{
    /* Initialize per-backend file flush context */
    WritebackContextInit(&BackendWritebackContext,
                         &backend_flush_after);
}

References backend_flush_after, BackendWritebackContext, and WritebackContextInit().

BufferManagerShmemInit()

static void BufferManagerShmemInit ( void *  arg )

static

Definition at line 120 of file buf_init.c.

{
    /*
     * Initialize all the buffer headers.
     */
    for (int i = 0; i < NBuffers; i++)
    {
        BufferDesc *buf = GetBufferDescriptor(i);
 
        ClearBufferTag(&buf->tag);
 
        pg_atomic_init_u64(&buf->state, 0);
        buf->wait_backend_pgprocno = INVALID_PROC_NUMBER;
 
        buf->buf_id = i;
 
        pgaio_wref_clear(&buf->io_wref);
 
        proclist_init(&buf->lock_waiters);
        ConditionVariableInit(BufferDescriptorGetIOCV(buf));
    }
 
    /* Initialize per-backend file flush context */
    WritebackContextInit(&BackendWritebackContext,
                         &backend_flush_after);
}

References backend_flush_after, BackendWritebackContext, buf, BufferDescriptorGetIOCV(), ClearBufferTag(), ConditionVariableInit(), GetBufferDescriptor(), i, INVALID_PROC_NUMBER, NBuffers, pg_atomic_init_u64(), pgaio_wref_clear(), proclist_init(), and WritebackContextInit().

BufferManagerShmemRequest()

static void BufferManagerShmemRequest ( void *  arg )

static

Definition at line 77 of file buf_init.c.

{
    ShmemRequestStruct(.name = "Buffer Descriptors",
                       .size = NBuffers * sizeof(BufferDescPadded),
    /* Align descriptors to a cacheline boundary. */
                       .alignment = PG_CACHE_LINE_SIZE,
                       .ptr = (void **) &BufferDescriptors,
        );
 
    ShmemRequestStruct(.name = "Buffer Blocks",
                       .size = NBuffers * (Size) BLCKSZ,
    /* Align buffer pool on IO page size boundary. */
                       .alignment = PG_IO_ALIGN_SIZE,
                       .ptr = (void **) &BufferBlocks,
        );
 
    ShmemRequestStruct(.name = "Buffer IO Condition Variables",
                       .size = NBuffers * sizeof(ConditionVariableMinimallyPadded),
    /* Align descriptors to a cacheline boundary. */
                       .alignment = PG_CACHE_LINE_SIZE,
                       .ptr = (void **) &BufferIOCVArray,
        );
 
    /*
     * The array used to sort to-be-checkpointed buffer ids is located in
     * shared memory, to avoid having to allocate significant amounts of
     * memory at runtime. As that'd be in the middle of a checkpoint, or when
     * the checkpointer is restarted, memory allocation failures would be
     * painful.
     */
    ShmemRequestStruct(.name = "Checkpoint BufferIds",
                       .size = NBuffers * sizeof(CkptSortItem),
                       .ptr = (void **) &CkptBufferIds,
        );
}

References BufferBlocks, BufferDescriptors, BufferIOCVArray, CkptBufferIds, fb(), name, NBuffers, PG_CACHE_LINE_SIZE, PG_IO_ALIGN_SIZE, and ShmemRequestStruct.

Variable Documentation

BackendWritebackContext

WritebackContext BackendWritebackContext

Definition at line 27 of file buf_init.c.

Referenced by BufferManagerShmemAttach(), BufferManagerShmemInit(), and GetVictimBuffer().

BufferBlocks

char* BufferBlocks

Definition at line 25 of file buf_init.c.

Referenced by BufferGetBlock(), and BufferManagerShmemRequest().

BufferDescriptors

BufferDescPadded* BufferDescriptors

Definition at line 24 of file buf_init.c.

Referenced by BufferManagerShmemRequest(), and GetBufferDescriptor().

BufferIOCVArray

ConditionVariableMinimallyPadded* BufferIOCVArray

Definition at line 26 of file buf_init.c.

Referenced by BufferDescriptorGetIOCV(), and BufferManagerShmemRequest().

BufferManagerShmemCallbacks

const ShmemCallbacks BufferManagerShmemCallbacks

Initial value:

= {
    .request_fn = BufferManagerShmemRequest,
    .init_fn = BufferManagerShmemInit,
    .attach_fn = BufferManagerShmemAttach,
}

Definition at line 34 of file buf_init.c.

                                                   {
    .request_fn = BufferManagerShmemRequest,
    .init_fn = BufferManagerShmemInit,
    .attach_fn = BufferManagerShmemAttach,
};

CkptBufferIds

CkptSortItem* CkptBufferIds

Definition at line 28 of file buf_init.c.

Referenced by BufferManagerShmemRequest(), and BufferSync().