/*
* emit a completed btree page, and release the working storage.
*/
static void
_bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno)
{
/* Ensure rd_smgr is open (could have been closed by relcache flush!) */
RelationOpenSmgr(wstate->index);
/* XLOG stuff */
if (wstate->btws_use_wal)
{
/* We use the heap NEWPAGE record type for this */
log_newpage(&wstate->index->rd_node, MAIN_FORKNUM, blkno, page);
}
else
{
/* Leave the page LSN zero if not WAL-logged, but set TLI anyway */
PageSetTLI(page, ThisTimeLineID);
}
/*
* If we have to write pages nonsequentially, fill in the space with
* zeroes until we come back and overwrite. This is not logically
* necessary on standard Unix filesystems (unwritten space will read as
* zeroes anyway), but it should help to avoid fragmentation. The dummy
* pages aren't WAL-logged though.
*/
while (blkno > wstate->btws_pages_written)
{
if (!wstate->btws_zeropage)
wstate->btws_zeropage = (Page) palloc0(BLCKSZ);
smgrextend(wstate->index->rd_smgr, MAIN_FORKNUM,
wstate->btws_pages_written++,
(char *) wstate->btws_zeropage,
true);
}
/*
* Now write the page. We say isTemp = true even if it's not a temp
* index, because there's no need for smgr to schedule an fsync for this
* write; we'll do it ourselves before ending the build.
*/
if (blkno == wstate->btws_pages_written)
{
/* extending the file... */
smgrextend(wstate->index->rd_smgr, MAIN_FORKNUM, blkno,
(char *) page, true);
wstate->btws_pages_written++;
}
else
{
/* overwriting a block we zero-filled before */
smgrwrite(wstate->index->rd_smgr, MAIN_FORKNUM, blkno,
(char *) page, true);
}
pfree(page);
}
/*
* SetMatViewToPopulated
* Indicate that the materialized view has been populated by its query.
*
* NOTE: The heap starts out in a state that doesn't look scannable, and can
* only transition from there to scannable at the time a new heap is created.
*
* NOTE: caller must be holding an appropriate lock on the relation.
*/
void
SetMatViewToPopulated(Relation relation)
{
Page page;
Assert(relation->rd_rel->relkind == RELKIND_MATVIEW);
Assert(relation->rd_ispopulated == false);
page = (Page) palloc(BLCKSZ);
PageInit(page, BLCKSZ, 0);
if (RelationNeedsWAL(relation))
log_newpage(&(relation->rd_node), MAIN_FORKNUM, 0, page);
RelationOpenSmgr(relation);
PageSetChecksumInplace(page, 0);
smgrextend(relation->rd_smgr, MAIN_FORKNUM, 0, (char *) page, true);
pfree(page);
smgrimmedsync(relation->rd_smgr, MAIN_FORKNUM);
RelationCacheInvalidateEntry(relation->rd_id);
}
/*
* Ensure that the visibility map fork is at least vm_nblocks long, extending
* it if necessary with zeroed pages.
*/
static void
vm_extend(Relation rel, BlockNumber vm_nblocks)
{
BlockNumber vm_nblocks_now;
Page pg;
pg = (Page) palloc(BLCKSZ);
PageInit(pg, BLCKSZ, 0);
/*
* We use the relation extension lock to lock out other backends trying to
* extend the visibility map at the same time. It also locks out extension
* of the main fork, unnecessarily, but extending the visibility map
* happens seldom enough that it doesn't seem worthwhile to have a
* separate lock tag type for it.
*
* Note that another backend might have extended or created the relation
* by the time we get the lock.
*/
LockRelationForExtension(rel, ExclusiveLock);
/* Might have to re-open if a cache flush happened */
RelationOpenSmgr(rel);
/*
* Create the file first if it doesn't exist. If smgr_vm_nblocks is
* positive then it must exist, no need for an smgrexists call.
*/
if ((rel->rd_smgr->smgr_vm_nblocks == 0 ||
rel->rd_smgr->smgr_vm_nblocks == InvalidBlockNumber) &&
!smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM))
smgrcreate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, false);
vm_nblocks_now = smgrnblocks(rel->rd_smgr, VISIBILITYMAP_FORKNUM);
/* Now extend the file */
while (vm_nblocks_now < vm_nblocks)
{
smgrextend(rel->rd_smgr, VISIBILITYMAP_FORKNUM, vm_nblocks_now,
(char *) pg, false);
vm_nblocks_now++;
}
/*
* Send a shared-inval message to force other backends to close any smgr
* references they may have for this rel, which we are about to change.
* This is a useful optimization because it means that backends don't have
* to keep checking for creation or extension of the file, which happens
* infrequently.
*/
CacheInvalidateSmgr(rel->rd_smgr->smgr_rnode);
/* Update local cache with the up-to-date size */
rel->rd_smgr->smgr_vm_nblocks = vm_nblocks_now;
UnlockRelationForExtension(rel, ExclusiveLock);
pfree(pg);
}
/*
* End a rewrite.
*
* state and any other resources are freed.
*/
void
end_heap_rewrite(RewriteState state)
{
HASH_SEQ_STATUS seq_status;
UnresolvedTup unresolved;
/*
* Write any remaining tuples in the UnresolvedTups table. If we have any
* left, they should in fact be dead, but let's err on the safe side.
*/
hash_seq_init(&seq_status, state->rs_unresolved_tups);
while ((unresolved = hash_seq_search(&seq_status)) != NULL)
{
ItemPointerSetInvalid(&unresolved->tuple->t_data->t_ctid);
raw_heap_insert(state, unresolved->tuple);
}
/* Write the last page, if any */
if (state->rs_buffer_valid)
{
if (state->rs_use_wal)
log_newpage(&state->rs_new_rel->rd_node,
MAIN_FORKNUM,
state->rs_blockno,
state->rs_buffer,
true);
RelationOpenSmgr(state->rs_new_rel);
PageSetChecksumInplace(state->rs_buffer, state->rs_blockno);
smgrextend(state->rs_new_rel->rd_smgr, MAIN_FORKNUM, state->rs_blockno,
(char *) state->rs_buffer, true);
}
/*
* If the rel is WAL-logged, must fsync before commit. We use heap_sync
* to ensure that the toast table gets fsync'd too.
*
* It's obvious that we must do this when not WAL-logging. It's less
* obvious that we have to do it even if we did WAL-log the pages. The
* reason is the same as in tablecmds.c's copy_relation_data(): we're
* writing data that's not in shared buffers, and so a CHECKPOINT
* occurring during the rewriteheap operation won't have fsync'd data we
* wrote before the checkpoint.
*/
if (RelationNeedsWAL(state->rs_new_rel))
heap_sync(state->rs_new_rel);
/* Deleting the context frees everything */
MemoryContextDelete(state->rs_cxt);
}
/*
* Ensure that the FSM fork is at least fsm_nblocks long, extending
* it if necessary with empty pages. And by empty, I mean pages filled
* with zeros, meaning there's no free space.
*/
static void
fsm_extend(Relation rel, BlockNumber fsm_nblocks)
{
BlockNumber fsm_nblocks_now;
Page pg;
pg = (Page) palloc(BLCKSZ);
PageInit(pg, BLCKSZ, 0);
/*
* We use the relation extension lock to lock out other backends trying to
* extend the FSM at the same time. It also locks out extension of the
* main fork, unnecessarily, but extending the FSM happens seldom enough
* that it doesn't seem worthwhile to have a separate lock tag type for
* it.
*
* Note that another backend might have extended or created the relation
* by the time we get the lock.
*/
LockRelationForExtension(rel, ExclusiveLock);
/* Might have to re-open if a cache flush happened */
RelationOpenSmgr(rel);
/*
* Create the FSM file first if it doesn't exist. If smgr_fsm_nblocks is
* positive then it must exist, no need for an smgrexists call.
*/
if ((rel->rd_smgr->smgr_fsm_nblocks == 0 ||
rel->rd_smgr->smgr_fsm_nblocks == InvalidBlockNumber) &&
!smgrexists(rel->rd_smgr, FSM_FORKNUM))
smgrcreate(rel->rd_smgr, FSM_FORKNUM, false);
fsm_nblocks_now = smgrnblocks(rel->rd_smgr, FSM_FORKNUM);
while (fsm_nblocks_now < fsm_nblocks)
{
PageSetChecksumInplace(pg, fsm_nblocks_now);
smgrextend(rel->rd_smgr, FSM_FORKNUM, fsm_nblocks_now,
(char *) pg, false);
fsm_nblocks_now++;
}
/* Update local cache with the up-to-date size */
rel->rd_smgr->smgr_fsm_nblocks = fsm_nblocks_now;
UnlockRelationForExtension(rel, ExclusiveLock);
pfree(pg);
}
/*
* _hash_alloc_buckets -- allocate a new splitpoint's worth of bucket pages
*
* This does not need to initialize the new bucket pages; we'll do that as
* each one is used by _hash_expandtable(). But we have to extend the logical
* EOF to the end of the splitpoint; otherwise the first overflow page
* allocated beyond the splitpoint will represent a noncontiguous access,
* which can confuse md.c (and will probably be forbidden by future changes
* to md.c).
*
* We do this by writing a page of zeroes at the end of the splitpoint range.
* We expect that the filesystem will ensure that the intervening pages read
* as zeroes too. On many filesystems this "hole" will not be allocated
* immediately, which means that the index file may end up more fragmented
* than if we forced it all to be allocated now; but since we don't scan
* hash indexes sequentially anyway, that probably doesn't matter.
*
* XXX It's annoying that this code is executed with the metapage lock held.
* We need to interlock against _hash_getovflpage() adding a new overflow page
* concurrently, but it'd likely be better to use LockRelationForExtension
* for the purpose. OTOH, adding a splitpoint is a very infrequent operation,
* so it may not be worth worrying about.
*
* Returns TRUE if successful, or FALSE if allocation failed due to
* BlockNumber overflow.
*/
static bool
_hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
{
BlockNumber lastblock;
BlockNumber endblock;
char zerobuf[BLCKSZ];
lastblock = firstblock + nblocks - 1;
/*
* Check for overflow in block number calculation; if so, we cannot
* extend the index anymore.
*/
if (lastblock < firstblock || lastblock == InvalidBlockNumber)
return false;
MemSet(zerobuf, 0, sizeof(zerobuf));
RelationOpenSmgr(rel);
/*
* XXX If the extension results in creation of new segment files,
* we have to make sure that each non-last file is correctly filled out to
* RELSEG_SIZE blocks. This ought to be done inside mdextend, but
* changing the smgr API seems best left for development cycle not late
* beta. Temporary fix for bug #2737.
*/
#ifndef LET_OS_MANAGE_FILESIZE
for (endblock = firstblock | (RELSEG_SIZE - 1);
endblock < lastblock;
endblock += RELSEG_SIZE)
smgrextend(rel->rd_smgr, endblock, zerobuf, rel->rd_istemp);
#endif
smgrextend(rel->rd_smgr, lastblock, zerobuf, rel->rd_istemp);
return true;
}
/*
* Ensure that the visibility map fork is at least vm_nblocks long, extending
* it if necessary with zeroed pages.
*/
static void
vm_extend(Relation rel, BlockNumber vm_nblocks)
{
BlockNumber vm_nblocks_now;
Page pg;
pg = (Page) palloc(BLCKSZ);
PageInit(pg, BLCKSZ, 0);
/*
* We use the relation extension lock to lock out other backends trying to
* extend the visibility map at the same time. It also locks out extension
* of the main fork, unnecessarily, but extending the visibility map
* happens seldom enough that it doesn't seem worthwhile to have a
* separate lock tag type for it.
*
* Note that another backend might have extended or created the relation
* before we get the lock.
*/
LockRelationForExtension(rel, ExclusiveLock);
/* Create the file first if it doesn't exist */
if ((rel->rd_vm_nblocks == 0 || rel->rd_vm_nblocks == InvalidBlockNumber)
&& !smgrexists(rel->rd_smgr, VISIBILITYMAP_FORKNUM))
{
smgrcreate(rel->rd_smgr, VISIBILITYMAP_FORKNUM, false);
vm_nblocks_now = 0;
}
else
vm_nblocks_now = smgrnblocks(rel->rd_smgr, VISIBILITYMAP_FORKNUM);
while (vm_nblocks_now < vm_nblocks)
{
smgrextend(rel->rd_smgr, VISIBILITYMAP_FORKNUM, vm_nblocks_now,
(char *) pg, rel->rd_istemp);
vm_nblocks_now++;
}
UnlockRelationForExtension(rel, ExclusiveLock);
pfree(pg);
/* Update the relcache with the up-to-date size */
if (!InRecovery)
CacheInvalidateRelcache(rel);
rel->rd_vm_nblocks = vm_nblocks_now;
}
/*
* _hash_alloc_buckets -- allocate a new splitpoint's worth of bucket pages
*
* This does not need to initialize the new bucket pages; we'll do that as
* each one is used by _hash_expandtable(). But we have to extend the logical
* EOF to the end of the splitpoint; this keeps smgr's idea of the EOF in
* sync with ours, so that we don't get complaints from smgr.
*
* We do this by writing a page of zeroes at the end of the splitpoint range.
* We expect that the filesystem will ensure that the intervening pages read
* as zeroes too. On many filesystems this "hole" will not be allocated
* immediately, which means that the index file may end up more fragmented
* than if we forced it all to be allocated now; but since we don't scan
* hash indexes sequentially anyway, that probably doesn't matter.
*
* XXX It's annoying that this code is executed with the metapage lock held.
* We need to interlock against _hash_addovflpage() adding a new overflow page
* concurrently, but it'd likely be better to use LockRelationForExtension
* for the purpose. OTOH, adding a splitpoint is a very infrequent operation,
* so it may not be worth worrying about.
*
* Returns TRUE if successful, or FALSE if allocation failed due to
* BlockNumber overflow.
*/
static bool
_hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
{
BlockNumber lastblock;
char zerobuf[BLCKSZ];
Page page;
HashPageOpaque ovflopaque;
lastblock = firstblock + nblocks - 1;
/*
* Check for overflow in block number calculation; if so, we cannot extend
* the index anymore.
*/
if (lastblock < firstblock || lastblock == InvalidBlockNumber)
return false;
page = (Page) zerobuf;
/*
* Initialize the page. Just zeroing the page won't work; see
* _hash_freeovflpage for similar usage. We take care to make the special
* space valid for the benefit of tools such as pageinspect.
*/
_hash_pageinit(page, BLCKSZ);
ovflopaque = (HashPageOpaque) PageGetSpecialPointer(page);
ovflopaque->hasho_prevblkno = InvalidBlockNumber;
ovflopaque->hasho_nextblkno = InvalidBlockNumber;
ovflopaque->hasho_bucket = -1;
ovflopaque->hasho_flag = LH_UNUSED_PAGE;
ovflopaque->hasho_page_id = HASHO_PAGE_ID;
if (RelationNeedsWAL(rel))
log_newpage(&rel->rd_node,
MAIN_FORKNUM,
lastblock,
zerobuf,
true);
RelationOpenSmgr(rel);
smgrextend(rel->rd_smgr, MAIN_FORKNUM, lastblock, zerobuf, false);
return true;
}
/*
* _hash_alloc_buckets -- allocate a new splitpoint's worth of bucket pages
*
* This does not need to initialize the new bucket pages; we'll do that as
* each one is used by _hash_expandtable(). But we have to extend the logical
* EOF to the end of the splitpoint; this keeps smgr's idea of the EOF in
* sync with ours, so that we don't get complaints from smgr.
*
* We do this by writing a page of zeroes at the end of the splitpoint range.
* We expect that the filesystem will ensure that the intervening pages read
* as zeroes too. On many filesystems this "hole" will not be allocated
* immediately, which means that the index file may end up more fragmented
* than if we forced it all to be allocated now; but since we don't scan
* hash indexes sequentially anyway, that probably doesn't matter.
*
* XXX It's annoying that this code is executed with the metapage lock held.
* We need to interlock against _hash_getovflpage() adding a new overflow page
* concurrently, but it'd likely be better to use LockRelationForExtension
* for the purpose. OTOH, adding a splitpoint is a very infrequent operation,
* so it may not be worth worrying about.
*
* Returns TRUE if successful, or FALSE if allocation failed due to
* BlockNumber overflow.
*/
static bool
_hash_alloc_buckets(Relation rel, BlockNumber firstblock, uint32 nblocks)
{
BlockNumber lastblock;
char zerobuf[BLCKSZ];
lastblock = firstblock + nblocks - 1;
/*
* Check for overflow in block number calculation; if so, we cannot extend
* the index anymore.
*/
if (lastblock < firstblock || lastblock == InvalidBlockNumber)
return false;
MemSet(zerobuf, 0, sizeof(zerobuf));
RelationOpenSmgr(rel);
smgrextend(rel->rd_smgr, MAIN_FORKNUM, lastblock, zerobuf, false);
return true;
}
/*
* Insert a tuple to the new relation. This has to track heap_insert
* and its subsidiary functions!
*
* t_self of the tuple is set to the new TID of the tuple. If t_ctid of the
* tuple is invalid on entry, it's replaced with the new TID as well (in
* the inserted data only, not in the caller's copy).
*/
static void
raw_heap_insert(RewriteState state, HeapTuple tup)
{
Page page = state->rs_buffer;
Size pageFreeSpace,
saveFreeSpace;
Size len;
OffsetNumber newoff;
HeapTuple heaptup;
/*
* If the new tuple is too big for storage or contains already toasted
* out-of-line attributes from some other relation, invoke the toaster.
*
* Note: below this point, heaptup is the data we actually intend to store
* into the relation; tup is the caller's original untoasted data.
*/
if (state->rs_new_rel->rd_rel->relkind == RELKIND_TOASTVALUE)
{
/* toast table entries should never be recursively toasted */
Assert(!HeapTupleHasExternal(tup));
heaptup = tup;
}
else if (HeapTupleHasExternal(tup) || tup->t_len > TOAST_TUPLE_THRESHOLD)
heaptup = toast_insert_or_update(state->rs_new_rel, tup, NULL,
HEAP_INSERT_SKIP_FSM |
(state->rs_use_wal ?
0 : HEAP_INSERT_SKIP_WAL));
else
heaptup = tup;
len = MAXALIGN(heaptup->t_len); /* be conservative */
/*
* 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(state->rs_new_rel,
HEAP_DEFAULT_FILLFACTOR);
/* Now we can check to see if there's enough free space already. */
if (state->rs_buffer_valid)
{
pageFreeSpace = PageGetHeapFreeSpace(page);
if (len + saveFreeSpace > pageFreeSpace)
{
/* Doesn't fit, so write out the existing page */
/* XLOG stuff */
if (state->rs_use_wal)
log_newpage(&state->rs_new_rel->rd_node,
MAIN_FORKNUM,
state->rs_blockno,
page,
true);
/*
* Now write the page. We say isTemp = true even if it's not a
* temp table, because there's no need for smgr to schedule an
* fsync for this write; we'll do it ourselves in
* end_heap_rewrite.
*/
RelationOpenSmgr(state->rs_new_rel);
PageSetChecksumInplace(page, state->rs_blockno);
smgrextend(state->rs_new_rel->rd_smgr, MAIN_FORKNUM,
state->rs_blockno, (char *) page, true);
state->rs_blockno++;
state->rs_buffer_valid = false;
}
}
if (!state->rs_buffer_valid)
{
/* Initialize a new empty page */
PageInit(page, BLCKSZ, 0);
state->rs_buffer_valid = true;
}
/* And now we can insert the tuple into the page */
newoff = PageAddItem(page, (Item) heaptup->t_data, heaptup->t_len,
InvalidOffsetNumber, false, true);
if (newoff == InvalidOffsetNumber)
elog(ERROR, "failed to add tuple");
/* Update caller's t_self to the actual position where it was stored */
ItemPointerSet(&(tup->t_self), state->rs_blockno, newoff);
/*
* Insert the correct position into CTID of the stored tuple, too, if the
* caller didn't supply a valid CTID.
*/
if (!ItemPointerIsValid(&tup->t_data->t_ctid))
{
ItemId newitemid;
HeapTupleHeader onpage_tup;
newitemid = PageGetItemId(page, newoff);
onpage_tup = (HeapTupleHeader) PageGetItem(page, newitemid);
onpage_tup->t_ctid = tup->t_self;
}
/* If heaptup is a private copy, release it. */
if (heaptup != tup)
heap_freetuple(heaptup);
}
/*
* emit a completed btree page, and release the working storage.
*/
static void
_bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno)
{
// Fetch gp_persistent_relation_node information that will be added to XLOG record.
RelationFetchGpRelationNodeForXLog(wstate->index);
/* Ensure rd_smgr is open (could have been closed by relcache flush!) */
RelationOpenSmgr(wstate->index);
/* XLOG stuff */
if (wstate->btws_use_wal)
{
_bt_lognewpage(wstate->index, page, blkno);
}
else
{
/* Leave the page LSN zero if not WAL-logged, but set TLI anyway */
PageSetTLI(page, ThisTimeLineID);
}
/*
* If we have to write pages nonsequentially, fill in the space with
* zeroes until we come back and overwrite. This is not logically
* necessary on standard Unix filesystems (unwritten space will read as
* zeroes anyway), but it should help to avoid fragmentation. The dummy
* pages aren't WAL-logged though.
*/
while (blkno > wstate->btws_pages_written)
{
if (!wstate->btws_zeropage)
wstate->btws_zeropage = (Page) palloc0(BLCKSZ);
// -------- MirroredLock ----------
// UNDONE: Unfortunately, I think we write temp relations to the mirror...
LWLockAcquire(MirroredLock, LW_SHARED);
smgrextend(wstate->index->rd_smgr, wstate->btws_pages_written++,
(char *) wstate->btws_zeropage,
true);
LWLockRelease(MirroredLock);
// -------- MirroredLock ----------
}
// -------- MirroredLock ----------
// UNDONE: Unfortunately, I think we write temp relations to the mirror...
LWLockAcquire(MirroredLock, LW_SHARED);
/*
* Now write the page. We say isTemp = true even if it's not a temp
* index, because there's no need for smgr to schedule an fsync for this
* write; we'll do it ourselves before ending the build.
*/
if (blkno == wstate->btws_pages_written)
{
/* extending the file... */
smgrextend(wstate->index->rd_smgr, blkno, (char *) page, true);
wstate->btws_pages_written++;
}
else
{
/* overwriting a block we zero-filled before */
smgrwrite(wstate->index->rd_smgr, blkno, (char *) page, true);
}
LWLockRelease(MirroredLock);
// -------- MirroredLock ----------
pfree(page);
}
