hio.c File Reference

#include "postgres.h"
#include "access/heapam.h"
#include "access/hio.h"
#include "access/htup_details.h"
#include "access/visibilitymap.h"
#include "storage/bufmgr.h"
#include "storage/freespace.h"
#include "storage/lmgr.h"
#include "storage/smgr.h"

Include dependency graph for hio.c:

Go to the source code of this file.

Functions
void	RelationPutHeapTuple (Relation relation, Buffer buffer, HeapTuple tuple, bool token)
static Buffer	ReadBufferBI (Relation relation, BlockNumber targetBlock, ReadBufferMode mode, BulkInsertState bistate)
static void	GetVisibilityMapPins (Relation relation, Buffer buffer1, Buffer buffer2, BlockNumber block1, BlockNumber block2, Buffer *vmbuffer1, Buffer *vmbuffer2)
static void	RelationAddExtraBlocks (Relation relation, BulkInsertState bistate)
Buffer	RelationGetBufferForTuple (Relation relation, Size len, Buffer otherBuffer, int options, BulkInsertState bistate, Buffer *vmbuffer, Buffer *vmbuffer_other)

Function Documentation

GetVisibilityMapPins()

static void GetVisibilityMapPins ( Relation  relation, Buffer  buffer1, Buffer  buffer2, BlockNumber  block1, BlockNumber  block2, Buffer *  vmbuffer1, Buffer *  vmbuffer2  )

static

Definition at line 139 of file hio.c.

{
    bool        need_to_pin_buffer1;
    bool        need_to_pin_buffer2;
 
    Assert(BufferIsValid(buffer1));
    Assert(buffer2 == InvalidBuffer || block1 <= block2);
 
    while (1)
    {
        /* Figure out which pins we need but don't have. */
        need_to_pin_buffer1 = PageIsAllVisible(BufferGetPage(buffer1))
            && !visibilitymap_pin_ok(block1, *vmbuffer1);
        need_to_pin_buffer2 = buffer2 != InvalidBuffer
            && PageIsAllVisible(BufferGetPage(buffer2))
            && !visibilitymap_pin_ok(block2, *vmbuffer2);
        if (!need_to_pin_buffer1 && !need_to_pin_buffer2)
            return;
 
        /* We must unlock both buffers before doing any I/O. */
        LockBuffer(buffer1, BUFFER_LOCK_UNLOCK);
        if (buffer2 != InvalidBuffer && buffer2 != buffer1)
            LockBuffer(buffer2, BUFFER_LOCK_UNLOCK);
 
        /* Get pins. */
        if (need_to_pin_buffer1)
            visibilitymap_pin(relation, block1, vmbuffer1);
        if (need_to_pin_buffer2)
            visibilitymap_pin(relation, block2, vmbuffer2);
 
        /* Relock buffers. */
        LockBuffer(buffer1, BUFFER_LOCK_EXCLUSIVE);
        if (buffer2 != InvalidBuffer && buffer2 != buffer1)
            LockBuffer(buffer2, BUFFER_LOCK_EXCLUSIVE);
 
        /*
         * If there are two buffers involved and we pinned just one of them,
         * it's possible that the second one became all-visible while we were
         * busy pinning the first one.  If it looks like that's a possible
         * scenario, we'll need to make a second pass through this loop.
         */
        if (buffer2 == InvalidBuffer || buffer1 == buffer2
            || (need_to_pin_buffer1 && need_to_pin_buffer2))
            break;
    }
}

References Assert(), BUFFER_LOCK_EXCLUSIVE, BUFFER_LOCK_UNLOCK, BufferGetPage(), BufferIsValid(), InvalidBuffer, LockBuffer(), PageIsAllVisible(), visibilitymap_pin(), and visibilitymap_pin_ok().

Referenced by RelationGetBufferForTuple().

ReadBufferBI()

static Buffer ReadBufferBI ( Relation  relation, BlockNumber  targetBlock, ReadBufferMode  mode, BulkInsertState  bistate  )

static

Definition at line 89 of file hio.c.

{
    Buffer      buffer;
 
    /* If not bulk-insert, exactly like ReadBuffer */
    if (!bistate)
        return ReadBufferExtended(relation, MAIN_FORKNUM, targetBlock,
                                  mode, NULL);
 
    /* If we have the desired block already pinned, re-pin and return it */
    if (bistate->current_buf != InvalidBuffer)
    {
        if (BufferGetBlockNumber(bistate->current_buf) == targetBlock)
        {
            /*
             * Currently the LOCK variants are only used for extending
             * relation, which should never reach this branch.
             */
            Assert(mode != RBM_ZERO_AND_LOCK &&
                   mode != RBM_ZERO_AND_CLEANUP_LOCK);
 
            IncrBufferRefCount(bistate->current_buf);
            return bistate->current_buf;
        }
        /* ... else drop the old buffer */
        ReleaseBuffer(bistate->current_buf);
        bistate->current_buf = InvalidBuffer;
    }
 
    /* Perform a read using the buffer strategy */
    buffer = ReadBufferExtended(relation, MAIN_FORKNUM, targetBlock,
                                mode, bistate->strategy);
 
    /* Save the selected block as target for future inserts */
    IncrBufferRefCount(buffer);
    bistate->current_buf = buffer;
 
    return buffer;
}

References Assert(), BufferGetBlockNumber(), BulkInsertStateData::current_buf, IncrBufferRefCount(), InvalidBuffer, MAIN_FORKNUM, mode, RBM_ZERO_AND_CLEANUP_LOCK, RBM_ZERO_AND_LOCK, ReadBufferExtended(), ReleaseBuffer(), and BulkInsertStateData::strategy.

Referenced by RelationAddExtraBlocks(), and RelationGetBufferForTuple().

RelationAddExtraBlocks()

static void RelationAddExtraBlocks ( Relation  relation, BulkInsertState  bistate  )

static

Definition at line 195 of file hio.c.

{
    BlockNumber blockNum,
                firstBlock = InvalidBlockNumber;
    int         extraBlocks;
    int         lockWaiters;
 
    /* Use the length of the lock wait queue to judge how much to extend. */
    lockWaiters = RelationExtensionLockWaiterCount(relation);
    if (lockWaiters <= 0)
        return;
 
    /*
     * It might seem like multiplying the number of lock waiters by as much as
     * 20 is too aggressive, but benchmarking revealed that smaller numbers
     * were insufficient.  512 is just an arbitrary cap to prevent
     * pathological results.
     */
    extraBlocks = Min(512, lockWaiters * 20);
 
    do
    {
        Buffer      buffer;
        Page        page;
        Size        freespace;
 
        /*
         * Extend by one page.  This should generally match the main-line
         * extension code in RelationGetBufferForTuple, except that we hold
         * the relation extension lock throughout, and we don't immediately
         * initialize the page (see below).
         */
        buffer = ReadBufferBI(relation, P_NEW, RBM_ZERO_AND_LOCK, bistate);
        page = BufferGetPage(buffer);
 
        if (!PageIsNew(page))
            elog(ERROR, "page %u of relation \"%s\" should be empty but is not",
                 BufferGetBlockNumber(buffer),
                 RelationGetRelationName(relation));
 
        /*
         * Add the page to the FSM without initializing. If we were to
         * initialize here, the page would potentially get flushed out to disk
         * before we add any useful content. There's no guarantee that that'd
         * happen before a potential crash, so we need to deal with
         * uninitialized pages anyway, thus avoid the potential for
         * unnecessary writes.
         */
 
        /* we'll need this info below */
        blockNum = BufferGetBlockNumber(buffer);
        freespace = BufferGetPageSize(buffer) - SizeOfPageHeaderData;
 
        UnlockReleaseBuffer(buffer);
 
        /* Remember first block number thus added. */
        if (firstBlock == InvalidBlockNumber)
            firstBlock = blockNum;
 
        /*
         * Immediately update the bottom level of the FSM.  This has a good
         * chance of making this page visible to other concurrently inserting
         * backends, and we want that to happen without delay.
         */
        RecordPageWithFreeSpace(relation, blockNum, freespace);
    }
    while (--extraBlocks > 0);
 
    /*
     * Updating the upper levels of the free space map is too expensive to do
     * for every block, but it's worth doing once at the end to make sure that
     * subsequent insertion activity sees all of those nifty free pages we
     * just inserted.
     */
    FreeSpaceMapVacuumRange(relation, firstBlock, blockNum + 1);
}

References BufferGetBlockNumber(), BufferGetPage(), BufferGetPageSize(), elog(), ERROR, FreeSpaceMapVacuumRange(), InvalidBlockNumber, Min, P_NEW, PageIsNew(), RBM_ZERO_AND_LOCK, ReadBufferBI(), RecordPageWithFreeSpace(), RelationExtensionLockWaiterCount(), RelationGetRelationName, SizeOfPageHeaderData, and UnlockReleaseBuffer().

Referenced by RelationGetBufferForTuple().

RelationGetBufferForTuple()

Buffer RelationGetBufferForTuple	(	Relation	relation,
		Size	len,
		Buffer	otherBuffer,
		int	options,
		BulkInsertState	bistate,
		Buffer *	vmbuffer,
		Buffer *	vmbuffer_other
	)

Definition at line 333 of file hio.c.

{
    bool        use_fsm = !(options & HEAP_INSERT_SKIP_FSM);
    Buffer      buffer = InvalidBuffer;
    Page        page;
    Size        nearlyEmptyFreeSpace,
                pageFreeSpace = 0,
                saveFreeSpace = 0,
                targetFreeSpace = 0;
    BlockNumber targetBlock,
                otherBlock;
    bool        needLock;
 
    len = MAXALIGN(len);        /* be conservative */
 
    /* Bulk insert is not supported for updates, only inserts. */
    Assert(otherBuffer == InvalidBuffer || !bistate);
 
    /*
     * If we're gonna fail for oversize tuple, do it right away
     */
    if (len > MaxHeapTupleSize)
        ereport(ERROR,
                (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
                 errmsg("row is too big: size %zu, maximum size %zu",
                        len, MaxHeapTupleSize)));
 
    /* Compute desired extra freespace due to fillfactor option */
    saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
                                                   HEAP_DEFAULT_FILLFACTOR);
 
    /*
     * Since pages without tuples can still have line pointers, we consider
     * pages "empty" when the unavailable space is slight.  This threshold is
     * somewhat arbitrary, but it should prevent most unnecessary relation
     * extensions while inserting large tuples into low-fillfactor tables.
     */
    nearlyEmptyFreeSpace = MaxHeapTupleSize -
        (MaxHeapTuplesPerPage / 8 * sizeof(ItemIdData));
    if (len + saveFreeSpace > nearlyEmptyFreeSpace)
        targetFreeSpace = Max(len, nearlyEmptyFreeSpace);
    else
        targetFreeSpace = len + saveFreeSpace;
 
    if (otherBuffer != InvalidBuffer)
        otherBlock = BufferGetBlockNumber(otherBuffer);
    else
        otherBlock = InvalidBlockNumber;    /* just to keep compiler quiet */
 
    /*
     * We first try to put the tuple on the same page we last inserted a tuple
     * on, as cached in the BulkInsertState or relcache entry.  If that
     * doesn't work, we ask the Free Space Map to locate a suitable page.
     * Since the FSM's info might be out of date, we have to be prepared to
     * loop around and retry multiple times. (To insure this isn't an infinite
     * loop, we must update the FSM with the correct amount of free space on
     * each page that proves not to be suitable.)  If the FSM has no record of
     * a page with enough free space, we give up and extend the relation.
     *
     * When use_fsm is false, we either put the tuple onto the existing target
     * page or extend the relation.
     */
    if (bistate && bistate->current_buf != InvalidBuffer)
        targetBlock = BufferGetBlockNumber(bistate->current_buf);
    else
        targetBlock = RelationGetTargetBlock(relation);
 
    if (targetBlock == InvalidBlockNumber && use_fsm)
    {
        /*
         * We have no cached target page, so ask the FSM for an initial
         * target.
         */
        targetBlock = GetPageWithFreeSpace(relation, targetFreeSpace);
    }
 
    /*
     * If the FSM knows nothing of the rel, try the last page before we give
     * up and extend.  This avoids one-tuple-per-page syndrome during
     * bootstrapping or in a recently-started system.
     */
    if (targetBlock == InvalidBlockNumber)
    {
        BlockNumber nblocks = RelationGetNumberOfBlocks(relation);
 
        if (nblocks > 0)
            targetBlock = nblocks - 1;
    }
 
loop:
    while (targetBlock != InvalidBlockNumber)
    {
        /*
         * Read and exclusive-lock the target block, as well as the other
         * block if one was given, taking suitable care with lock ordering and
         * the possibility they are the same block.
         *
         * If the page-level all-visible flag is set, caller will need to
         * clear both that and the corresponding visibility map bit.  However,
         * by the time we return, we'll have x-locked the buffer, and we don't
         * want to do any I/O while in that state.  So we check the bit here
         * before taking the lock, and pin the page if it appears necessary.
         * Checking without the lock creates a risk of getting the wrong
         * answer, so we'll have to recheck after acquiring the lock.
         */
        if (otherBuffer == InvalidBuffer)
        {
            /* easy case */
            buffer = ReadBufferBI(relation, targetBlock, RBM_NORMAL, bistate);
            if (PageIsAllVisible(BufferGetPage(buffer)))
                visibilitymap_pin(relation, targetBlock, vmbuffer);
 
            /*
             * If the page is empty, pin vmbuffer to set all_frozen bit later.
             */
            if ((options & HEAP_INSERT_FROZEN) &&
                (PageGetMaxOffsetNumber(BufferGetPage(buffer)) == 0))
                visibilitymap_pin(relation, targetBlock, vmbuffer);
 
            LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
        }
        else if (otherBlock == targetBlock)
        {
            /* also easy case */
            buffer = otherBuffer;
            if (PageIsAllVisible(BufferGetPage(buffer)))
                visibilitymap_pin(relation, targetBlock, vmbuffer);
            LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
        }
        else if (otherBlock < targetBlock)
        {
            /* lock other buffer first */
            buffer = ReadBuffer(relation, targetBlock);
            if (PageIsAllVisible(BufferGetPage(buffer)))
                visibilitymap_pin(relation, targetBlock, vmbuffer);
            LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);
            LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
        }
        else
        {
            /* lock target buffer first */
            buffer = ReadBuffer(relation, targetBlock);
            if (PageIsAllVisible(BufferGetPage(buffer)))
                visibilitymap_pin(relation, targetBlock, vmbuffer);
            LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
            LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);
        }
 
        /*
         * We now have the target page (and the other buffer, if any) pinned
         * and locked.  However, since our initial PageIsAllVisible checks
         * were performed before acquiring the lock, the results might now be
         * out of date, either for the selected victim buffer, or for the
         * other buffer passed by the caller.  In that case, we'll need to
         * give up our locks, go get the pin(s) we failed to get earlier, and
         * re-lock.  That's pretty painful, but hopefully shouldn't happen
         * often.
         *
         * Note that there's a small possibility that we didn't pin the page
         * above but still have the correct page pinned anyway, either because
         * we've already made a previous pass through this loop, or because
         * caller passed us the right page anyway.
         *
         * Note also that it's possible that by the time we get the pin and
         * retake the buffer locks, the visibility map bit will have been
         * cleared by some other backend anyway.  In that case, we'll have
         * done a bit of extra work for no gain, but there's no real harm
         * done.
         */
        if (otherBuffer == InvalidBuffer || targetBlock <= otherBlock)
            GetVisibilityMapPins(relation, buffer, otherBuffer,
                                 targetBlock, otherBlock, vmbuffer,
                                 vmbuffer_other);
        else
            GetVisibilityMapPins(relation, otherBuffer, buffer,
                                 otherBlock, targetBlock, vmbuffer_other,
                                 vmbuffer);
 
        /*
         * Now we can check to see if there's enough free space here. If so,
         * we're done.
         */
        page = BufferGetPage(buffer);
 
        /*
         * If necessary initialize page, it'll be used soon.  We could avoid
         * dirtying the buffer here, and rely on the caller to do so whenever
         * it puts a tuple onto the page, but there seems not much benefit in
         * doing so.
         */
        if (PageIsNew(page))
        {
            PageInit(page, BufferGetPageSize(buffer), 0);
            MarkBufferDirty(buffer);
        }
 
        pageFreeSpace = PageGetHeapFreeSpace(page);
        if (targetFreeSpace <= pageFreeSpace)
        {
            /* use this page as future insert target, too */
            RelationSetTargetBlock(relation, targetBlock);
            return buffer;
        }
 
        /*
         * Not enough space, so we must give up our page locks and pin (if
         * any) and prepare to look elsewhere.  We don't care which order we
         * unlock the two buffers in, so this can be slightly simpler than the
         * code above.
         */
        LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
        if (otherBuffer == InvalidBuffer)
            ReleaseBuffer(buffer);
        else if (otherBlock != targetBlock)
        {
            LockBuffer(otherBuffer, BUFFER_LOCK_UNLOCK);
            ReleaseBuffer(buffer);
        }
 
        /* Without FSM, always fall out of the loop and extend */
        if (!use_fsm)
            break;
 
        /*
         * Update FSM as to condition of this page, and ask for another page
         * to try.
         */
        targetBlock = RecordAndGetPageWithFreeSpace(relation,
                                                    targetBlock,
                                                    pageFreeSpace,
                                                    targetFreeSpace);
    }
 
    /*
     * Have to extend the relation.
     *
     * We have to use a lock to ensure no one else is extending the rel at the
     * same time, else we will both try to initialize the same new page.  We
     * can skip locking for new or temp relations, however, since no one else
     * could be accessing them.
     */
    needLock = !RELATION_IS_LOCAL(relation);
 
    /*
     * If we need the lock but are not able to acquire it immediately, we'll
     * consider extending the relation by multiple blocks at a time to manage
     * contention on the relation extension lock.  However, this only makes
     * sense if we're using the FSM; otherwise, there's no point.
     */
    if (needLock)
    {
        if (!use_fsm)
            LockRelationForExtension(relation, ExclusiveLock);
        else if (!ConditionalLockRelationForExtension(relation, ExclusiveLock))
        {
            /* Couldn't get the lock immediately; wait for it. */
            LockRelationForExtension(relation, ExclusiveLock);
 
            /*
             * Check if some other backend has extended a block for us while
             * we were waiting on the lock.
             */
            targetBlock = GetPageWithFreeSpace(relation, targetFreeSpace);
 
            /*
             * If some other waiter has already extended the relation, we
             * don't need to do so; just use the existing freespace.
             */
            if (targetBlock != InvalidBlockNumber)
            {
                UnlockRelationForExtension(relation, ExclusiveLock);
                goto loop;
            }
 
            /* Time to bulk-extend. */
            RelationAddExtraBlocks(relation, bistate);
        }
    }
 
    /*
     * In addition to whatever extension we performed above, we always add at
     * least one block to satisfy our own request.
     *
     * XXX This does an lseek - rather expensive - but at the moment it is the
     * only way to accurately determine how many blocks are in a relation.  Is
     * it worth keeping an accurate file length in shared memory someplace,
     * rather than relying on the kernel to do it for us?
     */
    buffer = ReadBufferBI(relation, P_NEW, RBM_ZERO_AND_LOCK, bistate);
 
    /*
     * We need to initialize the empty new page.  Double-check that it really
     * is empty (this should never happen, but if it does we don't want to
     * risk wiping out valid data).
     */
    page = BufferGetPage(buffer);
 
    if (!PageIsNew(page))
        elog(ERROR, "page %u of relation \"%s\" should be empty but is not",
             BufferGetBlockNumber(buffer),
             RelationGetRelationName(relation));
 
    PageInit(page, BufferGetPageSize(buffer), 0);
    MarkBufferDirty(buffer);
 
    /*
     * The page is empty, pin vmbuffer to set all_frozen bit.
     */
    if (options & HEAP_INSERT_FROZEN)
    {
        Assert(PageGetMaxOffsetNumber(BufferGetPage(buffer)) == 0);
        visibilitymap_pin(relation, BufferGetBlockNumber(buffer), vmbuffer);
    }
 
    /*
     * Release the file-extension lock; it's now OK for someone else to extend
     * the relation some more.
     */
    if (needLock)
        UnlockRelationForExtension(relation, ExclusiveLock);
 
    /*
     * Lock the other buffer. It's guaranteed to be of a lower page number
     * than the new page. To conform with the deadlock prevent rules, we ought
     * to lock otherBuffer first, but that would give other backends a chance
     * to put tuples on our page. To reduce the likelihood of that, attempt to
     * lock the other buffer conditionally, that's very likely to work.
     * Otherwise we need to lock buffers in the correct order, and retry if
     * the space has been used in the mean time.
     *
     * Alternatively, we could acquire the lock on otherBuffer before
     * extending the relation, but that'd require holding the lock while
     * performing IO, which seems worse than an unlikely retry.
     */
    if (otherBuffer != InvalidBuffer)
    {
        Assert(otherBuffer != buffer);
        targetBlock = BufferGetBlockNumber(buffer);
        Assert(targetBlock > otherBlock);
 
        if (unlikely(!ConditionalLockBuffer(otherBuffer)))
        {
            LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
            LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);
            LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
        }
 
        /*
         * Because the buffers were unlocked for a while, it's possible,
         * although unlikely, that an all-visible flag became set or that
         * somebody used up the available space in the new page.  We can use
         * GetVisibilityMapPins to deal with the first case.  In the second
         * case, just retry from start.
         */
        GetVisibilityMapPins(relation, otherBuffer, buffer,
                             otherBlock, targetBlock, vmbuffer_other,
                             vmbuffer);
 
        /*
         * Note that we have to check the available space even if our
         * conditional lock succeeded, because GetVisibilityMapPins might've
         * transiently released lock on the target buffer to acquire a VM pin
         * for the otherBuffer.
         */
        if (len > PageGetHeapFreeSpace(page))
        {
            LockBuffer(otherBuffer, BUFFER_LOCK_UNLOCK);
            UnlockReleaseBuffer(buffer);
 
            goto loop;
        }
    }
    else if (len > PageGetHeapFreeSpace(page))
    {
        /* We should not get here given the test at the top */
        elog(PANIC, "tuple is too big: size %zu", len);
    }
 
    /*
     * Remember the new page as our target for future insertions.
     *
     * XXX should we enter the new page into the free space map immediately,
     * or just keep it for this backend's exclusive use in the short run
     * (until VACUUM sees it)?  Seems to depend on whether you expect the
     * current backend to make more insertions or not, which is probably a
     * good bet most of the time.  So for now, don't add it to FSM yet.
     */
    RelationSetTargetBlock(relation, BufferGetBlockNumber(buffer));
 
    return buffer;
}

References Assert(), BUFFER_LOCK_EXCLUSIVE, BUFFER_LOCK_UNLOCK, BufferGetBlockNumber(), BufferGetPage(), BufferGetPageSize(), ConditionalLockBuffer(), ConditionalLockRelationForExtension(), BulkInsertStateData::current_buf, elog(), ereport, errcode(), errmsg(), ERROR, ExclusiveLock, GetPageWithFreeSpace(), GetVisibilityMapPins(), HEAP_DEFAULT_FILLFACTOR, HEAP_INSERT_FROZEN, HEAP_INSERT_SKIP_FSM, InvalidBlockNumber, InvalidBuffer, len, LockBuffer(), LockRelationForExtension(), MarkBufferDirty(), Max, MAXALIGN, MaxHeapTupleSize, MaxHeapTuplesPerPage, P_NEW, PageGetHeapFreeSpace(), PageGetMaxOffsetNumber(), PageInit(), PageIsAllVisible(), PageIsNew(), PANIC, RBM_NORMAL, RBM_ZERO_AND_LOCK, ReadBuffer(), ReadBufferBI(), RecordAndGetPageWithFreeSpace(), RELATION_IS_LOCAL, RelationAddExtraBlocks(), RelationGetNumberOfBlocks, RelationGetRelationName, RelationGetTargetBlock, RelationGetTargetPageFreeSpace, RelationSetTargetBlock, ReleaseBuffer(), unlikely, UnlockRelationForExtension(), UnlockReleaseBuffer(), and visibilitymap_pin().

Referenced by heap_insert(), heap_multi_insert(), and heap_update().

RelationPutHeapTuple()

void RelationPutHeapTuple	(	Relation	relation,
		Buffer	buffer,
		HeapTuple	tuple,
		bool	token
	)

Definition at line 36 of file hio.c.

{
    Page        pageHeader;
    OffsetNumber offnum;
 
    /*
     * A tuple that's being inserted speculatively should already have its
     * token set.
     */
    Assert(!token || HeapTupleHeaderIsSpeculative(tuple->t_data));
 
    /*
     * Do not allow tuples with invalid combinations of hint bits to be placed
     * on a page.  This combination is detected as corruption by the
     * contrib/amcheck logic, so if you disable this assertion, make
     * corresponding changes there.
     */
    Assert(!((tuple->t_data->t_infomask & HEAP_XMAX_COMMITTED) &&
             (tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI)));
 
    /* Add the tuple to the page */
    pageHeader = BufferGetPage(buffer);
 
    offnum = PageAddItem(pageHeader, (Item) tuple->t_data,
                         tuple->t_len, InvalidOffsetNumber, false, true);
 
    if (offnum == InvalidOffsetNumber)
        elog(PANIC, "failed to add tuple to page");
 
    /* Update tuple->t_self to the actual position where it was stored */
    ItemPointerSet(&(tuple->t_self), BufferGetBlockNumber(buffer), offnum);
 
    /*
     * Insert the correct position into CTID of the stored tuple, too (unless
     * this is a speculative insertion, in which case the token is held in
     * CTID field instead)
     */
    if (!token)
    {
        ItemId      itemId = PageGetItemId(pageHeader, offnum);
        HeapTupleHeader item = (HeapTupleHeader) PageGetItem(pageHeader, itemId);
 
        item->t_ctid = tuple->t_self;
    }
}

References Assert(), BufferGetBlockNumber(), BufferGetPage(), elog(), HEAP_XMAX_COMMITTED, HEAP_XMAX_IS_MULTI, HeapTupleHeaderIsSpeculative, InvalidOffsetNumber, ItemPointerSet(), PageAddItem, PageGetItem(), PageGetItemId(), PANIC, HeapTupleHeaderData::t_ctid, HeapTupleData::t_data, HeapTupleHeaderData::t_infomask, HeapTupleData::t_len, HeapTupleData::t_self, and token.

Referenced by heap_insert(), heap_multi_insert(), and heap_update().