greenplumn ginxlog 源码
greenplumn ginxlog 代码
文件路径：/src/backend/access/gin/ginxlog.c
/*-------------------------------------------------------------------------
*
* ginxlog.c
* WAL replay logic for inverted index.
*
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/access/gin/ginxlog.c
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/bufmask.h"
#include "access/gin_private.h"
#include "access/ginxlog.h"
#include "access/xlogutils.h"
#include "utils/memutils.h"
static MemoryContext opCtx; /* working memory for operations */
static void
ginRedoClearIncompleteSplit(XLogReaderState *record, uint8 block_id)
{
XLogRecPtr lsn = record->EndRecPtr;
Buffer buffer;
Page page;
if (XLogReadBufferForRedo(record, block_id, &buffer) == BLK_NEEDS_REDO)
{
page = (Page) BufferGetPage(buffer);
GinPageGetOpaque(page)->flags &= ~GIN_INCOMPLETE_SPLIT;
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
static void
ginRedoCreatePTree(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogCreatePostingTree *data = (ginxlogCreatePostingTree *) XLogRecGetData(record);
char *ptr;
Buffer buffer;
Page page;
buffer = XLogInitBufferForRedo(record, 0);
page = (Page) BufferGetPage(buffer);
GinInitBuffer(buffer, GIN_DATA | GIN_LEAF | GIN_COMPRESSED);
ptr = XLogRecGetData(record) + sizeof(ginxlogCreatePostingTree);
/* Place page data */
memcpy(GinDataLeafPageGetPostingList(page), ptr, data->size);
GinDataPageSetDataSize(page, data->size);
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
UnlockReleaseBuffer(buffer);
}
static void
ginRedoInsertEntry(Buffer buffer, bool isLeaf, BlockNumber rightblkno, void *rdata)
{
Page page = BufferGetPage(buffer);
ginxlogInsertEntry *data = (ginxlogInsertEntry *) rdata;
OffsetNumber offset = data->offset;
IndexTuple itup;
if (rightblkno != InvalidBlockNumber)
{
/* update link to right page after split */
Assert(!GinPageIsLeaf(page));
Assert(offset >= FirstOffsetNumber && offset <= PageGetMaxOffsetNumber(page));
itup = (IndexTuple) PageGetItem(page, PageGetItemId(page, offset));
GinSetDownlink(itup, rightblkno);
}
if (data->isDelete)
{
Assert(GinPageIsLeaf(page));
Assert(offset >= FirstOffsetNumber && offset <= PageGetMaxOffsetNumber(page));
PageIndexTupleDelete(page, offset);
}
itup = &data->tuple;
if (PageAddItem(page, (Item) itup, IndexTupleSize(itup), offset, false, false) == InvalidOffsetNumber)
{
RelFileNode node;
ForkNumber forknum;
BlockNumber blknum;
BufferGetTag(buffer, &node, &forknum, &blknum);
elog(ERROR, "failed to add item to index page in %u/%u/%u",
node.spcNode, node.dbNode, node.relNode);
}
}
/*
* Redo recompression of posting list. Doing all the changes in-place is not
* always possible, because it might require more space than we've on the page.
* Instead, once modification is required we copy unprocessed tail of the page
* into separately allocated chunk of memory for further reading original
* versions of segments. Thanks to that we don't bother about moving page data
* in-place.
*/
static void
ginRedoRecompress(Page page, ginxlogRecompressDataLeaf *data)
{
int actionno;
int segno;
GinPostingList *oldseg;
Pointer segmentend;
char *walbuf;
int totalsize;
Pointer tailCopy = NULL;
Pointer writePtr;
Pointer segptr;
/*
* If the page is in pre-9.4 format, convert to new format first.
*/
if (!GinPageIsCompressed(page))
{
ItemPointer uncompressed = (ItemPointer) GinDataPageGetData(page);
int nuncompressed = GinPageGetOpaque(page)->maxoff;
int npacked;
/*
* Empty leaf pages are deleted as part of vacuum, but leftmost and
* rightmost pages are never deleted. So, pg_upgrade'd from pre-9.4
* instances might contain empty leaf pages, and we need to handle
* them correctly.
*/
if (nuncompressed > 0)
{
GinPostingList *plist;
plist = ginCompressPostingList(uncompressed, nuncompressed,
BLCKSZ, &npacked);
totalsize = SizeOfGinPostingList(plist);
Assert(npacked == nuncompressed);
memcpy(GinDataLeafPageGetPostingList(page), plist, totalsize);
}
else
{
totalsize = 0;
}
GinDataPageSetDataSize(page, totalsize);
GinPageSetCompressed(page);
GinPageGetOpaque(page)->maxoff = InvalidOffsetNumber;
}
oldseg = GinDataLeafPageGetPostingList(page);
writePtr = (Pointer) oldseg;
segmentend = (Pointer) oldseg + GinDataLeafPageGetPostingListSize(page);
segno = 0;
walbuf = ((char *) data) + sizeof(ginxlogRecompressDataLeaf);
for (actionno = 0; actionno < data->nactions; actionno++)
{
uint8 a_segno = *((uint8 *) (walbuf++));
uint8 a_action = *((uint8 *) (walbuf++));
GinPostingList *newseg = NULL;
int newsegsize = 0;
ItemPointerData *items = NULL;
uint16 nitems = 0;
ItemPointerData *olditems;
int nolditems;
ItemPointerData *newitems;
int nnewitems;
int segsize;
/* Extract all the information we need from the WAL record */
if (a_action == GIN_SEGMENT_INSERT ||
a_action == GIN_SEGMENT_REPLACE)
{
newseg = (GinPostingList *) walbuf;
newsegsize = SizeOfGinPostingList(newseg);
walbuf += SHORTALIGN(newsegsize);
}
if (a_action == GIN_SEGMENT_ADDITEMS)
{
memcpy(&nitems, walbuf, sizeof(uint16));
walbuf += sizeof(uint16);
items = (ItemPointerData *) walbuf;
walbuf += nitems * sizeof(ItemPointerData);
}
/* Skip to the segment that this action concerns */
Assert(segno <= a_segno);
while (segno < a_segno)
{
/*
* Once modification is started and page tail is copied, we've to
* copy unmodified segments.
*/
segsize = SizeOfGinPostingList(oldseg);
if (tailCopy)
{
Assert(writePtr + segsize < PageGetSpecialPointer(page));
memcpy(writePtr, (Pointer) oldseg, segsize);
}
writePtr += segsize;
oldseg = GinNextPostingListSegment(oldseg);
segno++;
}
/*
* ADDITEMS action is handled like REPLACE, but the new segment to
* replace the old one is reconstructed using the old segment from
* disk and the new items from the WAL record.
*/
if (a_action == GIN_SEGMENT_ADDITEMS)
{
int npacked;
olditems = ginPostingListDecode(oldseg, &nolditems);
newitems = ginMergeItemPointers(items, nitems,
olditems, nolditems,
&nnewitems);
Assert(nnewitems == nolditems + nitems);
newseg = ginCompressPostingList(newitems, nnewitems,
BLCKSZ, &npacked);
Assert(npacked == nnewitems);
newsegsize = SizeOfGinPostingList(newseg);
a_action = GIN_SEGMENT_REPLACE;
}
segptr = (Pointer) oldseg;
if (segptr != segmentend)
segsize = SizeOfGinPostingList(oldseg);
else
{
/*
* Positioned after the last existing segment. Only INSERTs
* expected here.
*/
Assert(a_action == GIN_SEGMENT_INSERT);
segsize = 0;
}
/*
* We're about to start modification of the page. So, copy tail of
* the page if it's not done already.
*/
if (!tailCopy && segptr != segmentend)
{
int tailSize = segmentend - segptr;
tailCopy = (Pointer) palloc(tailSize);
memcpy(tailCopy, segptr, tailSize);
segptr = tailCopy;
oldseg = (GinPostingList *) segptr;
segmentend = segptr + tailSize;
}
switch (a_action)
{
case GIN_SEGMENT_DELETE:
segptr += segsize;
segno++;
break;
case GIN_SEGMENT_INSERT:
/* copy the new segment in place */
Assert(writePtr + newsegsize <= PageGetSpecialPointer(page));
memcpy(writePtr, newseg, newsegsize);
writePtr += newsegsize;
break;
case GIN_SEGMENT_REPLACE:
/* copy the new version of segment in place */
Assert(writePtr + newsegsize <= PageGetSpecialPointer(page));
memcpy(writePtr, newseg, newsegsize);
writePtr += newsegsize;
segptr += segsize;
segno++;
break;
default:
elog(ERROR, "unexpected GIN leaf action: %u", a_action);
}
oldseg = (GinPostingList *) segptr;
}
/* Copy the rest of unmodified segments if any. */
segptr = (Pointer) oldseg;
if (segptr != segmentend && tailCopy)
{
int restSize = segmentend - segptr;
Assert(writePtr + restSize <= PageGetSpecialPointer(page));
memcpy(writePtr, segptr, restSize);
writePtr += restSize;
}
totalsize = writePtr - (Pointer) GinDataLeafPageGetPostingList(page);
GinDataPageSetDataSize(page, totalsize);
}
static void
ginRedoInsertData(Buffer buffer, bool isLeaf, BlockNumber rightblkno, void *rdata)
{
Page page = BufferGetPage(buffer);
if (isLeaf)
{
ginxlogRecompressDataLeaf *data = (ginxlogRecompressDataLeaf *) rdata;
Assert(GinPageIsLeaf(page));
ginRedoRecompress(page, data);
}
else
{
ginxlogInsertDataInternal *data = (ginxlogInsertDataInternal *) rdata;
PostingItem *oldpitem;
Assert(!GinPageIsLeaf(page));
/* update link to right page after split */
oldpitem = GinDataPageGetPostingItem(page, data->offset);
PostingItemSetBlockNumber(oldpitem, rightblkno);
GinDataPageAddPostingItem(page, &data->newitem, data->offset);
}
}
static void
ginRedoInsert(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogInsert *data = (ginxlogInsert *) XLogRecGetData(record);
Buffer buffer;
#ifdef NOT_USED
BlockNumber leftChildBlkno = InvalidBlockNumber;
#endif
BlockNumber rightChildBlkno = InvalidBlockNumber;
bool isLeaf = (data->flags & GIN_INSERT_ISLEAF) != 0;
/*
* First clear incomplete-split flag on child page if this finishes a
* split.
*/
if (!isLeaf)
{
char *payload = XLogRecGetData(record) + sizeof(ginxlogInsert);
#ifdef NOT_USED
leftChildBlkno = BlockIdGetBlockNumber((BlockId) payload);
#endif
payload += sizeof(BlockIdData);
rightChildBlkno = BlockIdGetBlockNumber((BlockId) payload);
payload += sizeof(BlockIdData);
ginRedoClearIncompleteSplit(record, 1);
}
if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
{
Page page = BufferGetPage(buffer);
Size len;
char *payload = XLogRecGetBlockData(record, 0, &len);
/* How to insert the payload is tree-type specific */
if (data->flags & GIN_INSERT_ISDATA)
{
Assert(GinPageIsData(page));
ginRedoInsertData(buffer, isLeaf, rightChildBlkno, payload);
}
else
{
Assert(!GinPageIsData(page));
ginRedoInsertEntry(buffer, isLeaf, rightChildBlkno, payload);
}
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
static void
ginRedoSplit(XLogReaderState *record)
{
ginxlogSplit *data = (ginxlogSplit *) XLogRecGetData(record);
Buffer lbuffer,
rbuffer,
rootbuf;
bool isLeaf = (data->flags & GIN_INSERT_ISLEAF) != 0;
bool isRoot = (data->flags & GIN_SPLIT_ROOT) != 0;
/*
* First clear incomplete-split flag on child page if this finishes a
* split
*/
if (!isLeaf)
ginRedoClearIncompleteSplit(record, 3);
if (XLogReadBufferForRedo(record, 0, &lbuffer) != BLK_RESTORED)
elog(ERROR, "GIN split record did not contain a full-page image of left page");
if (XLogReadBufferForRedo(record, 1, &rbuffer) != BLK_RESTORED)
elog(ERROR, "GIN split record did not contain a full-page image of right page");
if (isRoot)
{
if (XLogReadBufferForRedo(record, 2, &rootbuf) != BLK_RESTORED)
elog(ERROR, "GIN split record did not contain a full-page image of root page");
UnlockReleaseBuffer(rootbuf);
}
UnlockReleaseBuffer(rbuffer);
UnlockReleaseBuffer(lbuffer);
}
/*
* VACUUM_PAGE record contains simply a full image of the page, similar to
* an XLOG_FPI record.
*/
static void
ginRedoVacuumPage(XLogReaderState *record)
{
Buffer buffer;
if (XLogReadBufferForRedo(record, 0, &buffer) != BLK_RESTORED)
{
elog(ERROR, "replay of gin entry tree page vacuum did not restore the page");
}
UnlockReleaseBuffer(buffer);
}
static void
ginRedoVacuumDataLeafPage(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
Buffer buffer;
if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
{
Page page = BufferGetPage(buffer);
Size len;
ginxlogVacuumDataLeafPage *xlrec;
xlrec = (ginxlogVacuumDataLeafPage *) XLogRecGetBlockData(record, 0, &len);
Assert(GinPageIsLeaf(page));
Assert(GinPageIsData(page));
ginRedoRecompress(page, &xlrec->data);
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
static void
ginRedoDeletePage(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogDeletePage *data = (ginxlogDeletePage *) XLogRecGetData(record);
Buffer dbuffer;
Buffer pbuffer;
Buffer lbuffer;
Page page;
/*
* Lock left page first in order to prevent possible deadlock with
* ginStepRight().
*/
if (XLogReadBufferForRedo(record, 2, &lbuffer) == BLK_NEEDS_REDO)
{
page = BufferGetPage(lbuffer);
Assert(GinPageIsData(page));
GinPageGetOpaque(page)->rightlink = data->rightLink;
PageSetLSN(page, lsn);
MarkBufferDirty(lbuffer);
}
if (XLogReadBufferForRedo(record, 0, &dbuffer) == BLK_NEEDS_REDO)
{
page = BufferGetPage(dbuffer);
Assert(GinPageIsData(page));
GinPageGetOpaque(page)->flags = GIN_DELETED;
GinPageSetDeleteXid(page, data->deleteXid);
PageSetLSN(page, lsn);
MarkBufferDirty(dbuffer);
}
if (XLogReadBufferForRedo(record, 1, &pbuffer) == BLK_NEEDS_REDO)
{
page = BufferGetPage(pbuffer);
Assert(GinPageIsData(page));
Assert(!GinPageIsLeaf(page));
GinPageDeletePostingItem(page, data->parentOffset);
PageSetLSN(page, lsn);
MarkBufferDirty(pbuffer);
}
if (BufferIsValid(lbuffer))
UnlockReleaseBuffer(lbuffer);
if (BufferIsValid(pbuffer))
UnlockReleaseBuffer(pbuffer);
if (BufferIsValid(dbuffer))
UnlockReleaseBuffer(dbuffer);
}
static void
ginRedoUpdateMetapage(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogUpdateMeta *data = (ginxlogUpdateMeta *) XLogRecGetData(record);
Buffer metabuffer;
Page metapage;
Buffer buffer;
/*
* Restore the metapage. This is essentially the same as a full-page
* image, so restore the metapage unconditionally without looking at the
* LSN, to avoid torn page hazards.
*/
metabuffer = XLogInitBufferForRedo(record, 0);
Assert(BufferGetBlockNumber(metabuffer) == GIN_METAPAGE_BLKNO);
metapage = BufferGetPage(metabuffer);
GinInitMetabuffer(metabuffer);
memcpy(GinPageGetMeta(metapage), &data->metadata, sizeof(GinMetaPageData));
PageSetLSN(metapage, lsn);
MarkBufferDirty(metabuffer);
if (data->ntuples > 0)
{
/*
* insert into tail page
*/
if (XLogReadBufferForRedo(record, 1, &buffer) == BLK_NEEDS_REDO)
{
Page page = BufferGetPage(buffer);
OffsetNumber off;
int i;
Size tupsize;
char *payload;
IndexTuple tuples;
Size totaltupsize;
payload = XLogRecGetBlockData(record, 1, &totaltupsize);
tuples = (IndexTuple) payload;
if (PageIsEmpty(page))
off = FirstOffsetNumber;
else
off = OffsetNumberNext(PageGetMaxOffsetNumber(page));
for (i = 0; i < data->ntuples; i++)
{
tupsize = IndexTupleSize(tuples);
if (PageAddItem(page, (Item) tuples, tupsize, off,
false, false) == InvalidOffsetNumber)
elog(ERROR, "failed to add item to index page");
tuples = (IndexTuple) (((char *) tuples) + tupsize);
off++;
}
Assert(payload + totaltupsize == (char *) tuples);
/*
* Increase counter of heap tuples
*/
GinPageGetOpaque(page)->maxoff++;
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
else if (data->prevTail != InvalidBlockNumber)
{
/*
* New tail
*/
if (XLogReadBufferForRedo(record, 1, &buffer) == BLK_NEEDS_REDO)
{
Page page = BufferGetPage(buffer);
GinPageGetOpaque(page)->rightlink = data->newRightlink;
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
}
if (BufferIsValid(buffer))
UnlockReleaseBuffer(buffer);
}
UnlockReleaseBuffer(metabuffer);
}
static void
ginRedoInsertListPage(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogInsertListPage *data = (ginxlogInsertListPage *) XLogRecGetData(record);
Buffer buffer;
Page page;
OffsetNumber l,
off = FirstOffsetNumber;
int i,
tupsize;
char *payload;
IndexTuple tuples;
Size totaltupsize;
/* We always re-initialize the page. */
buffer = XLogInitBufferForRedo(record, 0);
page = BufferGetPage(buffer);
GinInitBuffer(buffer, GIN_LIST);
GinPageGetOpaque(page)->rightlink = data->rightlink;
if (data->rightlink == InvalidBlockNumber)
{
/* tail of sublist */
GinPageSetFullRow(page);
GinPageGetOpaque(page)->maxoff = 1;
}
else
{
GinPageGetOpaque(page)->maxoff = 0;
}
payload = XLogRecGetBlockData(record, 0, &totaltupsize);
tuples = (IndexTuple) payload;
for (i = 0; i < data->ntuples; i++)
{
tupsize = IndexTupleSize(tuples);
l = PageAddItem(page, (Item) tuples, tupsize, off, false, false);
if (l == InvalidOffsetNumber)
elog(ERROR, "failed to add item to index page");
tuples = (IndexTuple) (((char *) tuples) + tupsize);
off++;
}
Assert((char *) tuples == payload + totaltupsize);
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
UnlockReleaseBuffer(buffer);
}
static void
ginRedoDeleteListPages(XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
ginxlogDeleteListPages *data = (ginxlogDeleteListPages *) XLogRecGetData(record);
Buffer metabuffer;
Page metapage;
int i;
metabuffer = XLogInitBufferForRedo(record, 0);
Assert(BufferGetBlockNumber(metabuffer) == GIN_METAPAGE_BLKNO);
metapage = BufferGetPage(metabuffer);
GinInitMetabuffer(metabuffer);
memcpy(GinPageGetMeta(metapage), &data->metadata, sizeof(GinMetaPageData));
PageSetLSN(metapage, lsn);
MarkBufferDirty(metabuffer);
/*
* In normal operation, shiftList() takes exclusive lock on all the
* pages-to-be-deleted simultaneously. During replay, however, it should
* be all right to lock them one at a time. This is dependent on the fact
* that we are deleting pages from the head of the list, and that readers
* share-lock the next page before releasing the one they are on. So we
* cannot get past a reader that is on, or due to visit, any page we are
* going to delete. New incoming readers will block behind our metapage
* lock and then see a fully updated page list.
*
* No full-page images are taken of the deleted pages. Instead, they are
* re-initialized as empty, deleted pages. Their right-links don't need to
* be preserved, because no new readers can see the pages, as explained
* above.
*/
for (i = 0; i < data->ndeleted; i++)
{
Buffer buffer;
Page page;
buffer = XLogInitBufferForRedo(record, i + 1);
page = BufferGetPage(buffer);
GinInitBuffer(buffer, GIN_DELETED);
PageSetLSN(page, lsn);
MarkBufferDirty(buffer);
UnlockReleaseBuffer(buffer);
}
UnlockReleaseBuffer(metabuffer);
}
void
gin_redo(XLogReaderState *record)
{
uint8 info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
MemoryContext oldCtx;
/*
* GIN indexes do not require any conflict processing. NB: If we ever
* implement a similar optimization as we have in b-tree, and remove
* killed tuples outside VACUUM, we'll need to handle that here.
*/
oldCtx = MemoryContextSwitchTo(opCtx);
switch (info)
{
case XLOG_GIN_CREATE_PTREE:
ginRedoCreatePTree(record);
break;
case XLOG_GIN_INSERT:
ginRedoInsert(record);
break;
case XLOG_GIN_SPLIT:
ginRedoSplit(record);
break;
case XLOG_GIN_VACUUM_PAGE:
ginRedoVacuumPage(record);
break;
case XLOG_GIN_VACUUM_DATA_LEAF_PAGE:
ginRedoVacuumDataLeafPage(record);
break;
case XLOG_GIN_DELETE_PAGE:
ginRedoDeletePage(record);
break;
case XLOG_GIN_UPDATE_META_PAGE:
ginRedoUpdateMetapage(record);
break;
case XLOG_GIN_INSERT_LISTPAGE:
ginRedoInsertListPage(record);
break;
case XLOG_GIN_DELETE_LISTPAGE:
ginRedoDeleteListPages(record);
break;
default:
elog(PANIC, "gin_redo: unknown op code %u", info);
}
MemoryContextSwitchTo(oldCtx);
MemoryContextReset(opCtx);
}
void
gin_xlog_startup(void)
{
opCtx = AllocSetContextCreate(CurrentMemoryContext,
"GIN recovery temporary context",
ALLOCSET_DEFAULT_SIZES);
}
void
gin_xlog_cleanup(void)
{
MemoryContextDelete(opCtx);
opCtx = NULL;
}
/*
* Mask a GIN page before running consistency checks on it.
*/
void
gin_mask(char *pagedata, BlockNumber blkno)
{
Page page = (Page) pagedata;
PageHeader pagehdr = (PageHeader) page;
GinPageOpaque opaque;
mask_page_lsn_and_checksum(page);
opaque = GinPageGetOpaque(page);
mask_page_hint_bits(page);
/*
* For a GIN_DELETED page, the page is initialized to empty. Hence, mask
* the whole page content. For other pages, mask the hole if pd_lower
* appears to have been set correctly.
*/
if (opaque->flags & GIN_DELETED)
mask_page_content(page);
else if (pagehdr->pd_lower > SizeOfPageHeaderData)
mask_unused_space(page);
}
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