diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtinsert.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtinsert.c | 107 |
1 files changed, 62 insertions, 45 deletions
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index c1671ce333..775eaca242 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.155 2007/03/25 19:45:14 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.156 2007/04/11 20:47:37 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -49,7 +49,7 @@ static TransactionId _bt_check_unique(Relation rel, IndexTuple itup, Relation heapRel, Buffer buf, OffsetNumber ioffset, ScanKey itup_scankey); static void _bt_findinsertloc(Relation rel, - Buffer *bufptr, + Buffer *bufptr, OffsetNumber *offsetptr, int keysz, ScanKey scankey, @@ -66,7 +66,7 @@ static OffsetNumber _bt_findsplitloc(Relation rel, Page page, OffsetNumber newitemoff, Size newitemsz, bool *newitemonleft); -static void _bt_checksplitloc(FindSplitData *state, +static void _bt_checksplitloc(FindSplitData *state, OffsetNumber firstoldonright, bool newitemonleft, int dataitemstoleft, Size firstoldonrightsz); static void _bt_pgaddtup(Relation rel, Page page, @@ -459,7 +459,7 @@ _bt_findinsertloc(Relation rel, * the hint supplied by the caller invalid */ vacuumed = true; - if (PageGetFreeSpace(page) >= itemsz) + if (PageGetFreeSpace(page) >= itemsz) break; /* OK, now we have enough space */ } @@ -506,7 +506,7 @@ _bt_findinsertloc(Relation rel, * moved right at all, we know we should insert at the start of the * page. If we didn't move right, we can use the firstlegaloff hint * if the caller supplied one, unless we vacuumed the page which - * might have moved tuples around making the hint invalid. If we + * might have moved tuples around making the hint invalid. If we * didn't move right or can't use the hint, find the position * by searching. */ @@ -779,8 +779,6 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, Buffer sbuf = InvalidBuffer; Page spage = NULL; BTPageOpaque sopaque = NULL; - OffsetNumber itup_off = 0; - BlockNumber itup_blkno = 0; Size itemsz; ItemId itemid; IndexTuple item; @@ -798,6 +796,14 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, _bt_pageinit(leftpage, BufferGetPageSize(buf)); /* rightpage was already initialized by _bt_getbuf */ + /* + * Copy the original page's LSN and TLI into leftpage, which will become + * the updated version of the page. We need this because XLogInsert will + * examine these fields and possibly dump them in a page image. + */ + PageSetLSN(leftpage, PageGetLSN(origpage)); + PageSetTLI(leftpage, PageGetTLI(origpage)); + /* init btree private data */ oopaque = (BTPageOpaque) PageGetSpecialPointer(origpage); lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage); @@ -864,7 +870,10 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, leftoff = OffsetNumberNext(leftoff); /* - * Now transfer all the data items to the appropriate page + * Now transfer all the data items to the appropriate page. + * + * Note: we *must* insert at least the right page's items in item-number + * order, for the benefit of _bt_restore_page(). */ maxoff = PageGetMaxOffsetNumber(origpage); @@ -881,16 +890,12 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, { _bt_pgaddtup(rel, leftpage, newitemsz, newitem, leftoff, "left sibling"); - itup_off = leftoff; - itup_blkno = BufferGetBlockNumber(buf); leftoff = OffsetNumberNext(leftoff); } else { _bt_pgaddtup(rel, rightpage, newitemsz, newitem, rightoff, "right sibling"); - itup_off = rightoff; - itup_blkno = BufferGetBlockNumber(rbuf); rightoff = OffsetNumberNext(rightoff); } } @@ -921,8 +926,6 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, Assert(!newitemonleft); _bt_pgaddtup(rel, rightpage, newitemsz, newitem, rightoff, "right sibling"); - itup_off = rightoff; - itup_blkno = BufferGetBlockNumber(rbuf); rightoff = OffsetNumberNext(rightoff); } @@ -961,7 +964,7 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, /* * Right sibling is locked, new siblings are prepared, but original page - * is not updated yet. Log changes before continuing. + * is not updated yet. * * NO EREPORT(ERROR) till right sibling is updated. We can get away with * not starting the critical section till here because we haven't been @@ -970,15 +973,6 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, */ START_CRIT_SECTION(); - MarkBufferDirty(buf); - MarkBufferDirty(rbuf); - - if (!P_RIGHTMOST(ropaque)) - { - sopaque->btpo_prev = BufferGetBlockNumber(rbuf); - MarkBufferDirty(sbuf); - } - /* * By here, the original data page has been split into two new halves, and * these are correct. The algorithm requires that the left page never @@ -994,6 +988,15 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, */ PageRestoreTempPage(leftpage, origpage); + MarkBufferDirty(buf); + MarkBufferDirty(rbuf); + + if (!P_RIGHTMOST(ropaque)) + { + sopaque->btpo_prev = BufferGetBlockNumber(rbuf); + MarkBufferDirty(sbuf); + } + /* XLOG stuff */ if (!rel->rd_istemp) { @@ -1006,9 +1009,9 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, xlrec.node = rel->rd_node; xlrec.leftsib = BufferGetBlockNumber(buf); xlrec.rightsib = BufferGetBlockNumber(rbuf); - xlrec.firstright = firstright; xlrec.rnext = ropaque->btpo_next; xlrec.level = ropaque->btpo.level; + xlrec.firstright = firstright; rdata[0].data = (char *) &xlrec; rdata[0].len = SizeOfBtreeSplit; @@ -1027,14 +1030,18 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, lastrdata->buffer = InvalidBuffer; } - /* Log the new item, if it was inserted on the left page. If it was - * put on the right page, we don't need to explicitly WAL log it - * because it's included with all the other items on the right page. + /* + * Log the new item and its offset, if it was inserted on the left + * page. (If it was put on the right page, we don't need to explicitly + * WAL log it because it's included with all the other items on the + * right page.) Show these as belonging to the left page buffer, + * so that they are not stored if XLogInsert decides it needs a + * full-page image of the left page. */ - lastrdata->next = lastrdata + 1; - lastrdata++; if (newitemonleft) { + lastrdata->next = lastrdata + 1; + lastrdata++; lastrdata->data = (char *) &newitemoff; lastrdata->len = sizeof(OffsetNumber); lastrdata->buffer = buf; /* backup block 1 */ @@ -1042,39 +1049,49 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, lastrdata->next = lastrdata + 1; lastrdata++; - lastrdata->data = (char *)newitem; - lastrdata->len = newitemsz; + lastrdata->data = (char *) newitem; + lastrdata->len = MAXALIGN(newitemsz); lastrdata->buffer = buf; /* backup block 1 */ lastrdata->buffer_std = true; } else { + /* + * Although we don't need to WAL-log the new item, we still + * need XLogInsert to consider storing a full-page image of the + * left page, so make an empty entry referencing that buffer. + * This also ensures that the left page is always backup block 1. + */ + lastrdata->next = lastrdata + 1; + lastrdata++; lastrdata->data = NULL; lastrdata->len = 0; lastrdata->buffer = buf; /* backup block 1 */ lastrdata->buffer_std = true; } - /* Log the contents of the right page in the format understood by + /* + * Log the contents of the right page in the format understood by * _bt_restore_page(). We set lastrdata->buffer to InvalidBuffer, - * because we're going to recreate the whole page anyway. + * because we're going to recreate the whole page anyway, so it + * should never be stored by XLogInsert. * * Direct access to page is not good but faster - we should implement * some new func in page API. Note we only store the tuples - * themselves, knowing that the item pointers are in the same order - * and can be reconstructed by scanning the tuples. See comments for + * themselves, knowing that they were inserted in item-number order + * and so the item pointers can be reconstructed. See comments for * _bt_restore_page(). */ lastrdata->next = lastrdata + 1; lastrdata++; - lastrdata->data = (char *) rightpage + + lastrdata->data = (char *) rightpage + ((PageHeader) rightpage)->pd_upper; lastrdata->len = ((PageHeader) rightpage)->pd_special - ((PageHeader) rightpage)->pd_upper; lastrdata->buffer = InvalidBuffer; - /* Log the right sibling, because we've changed it's prev-pointer. */ + /* Log the right sibling, because we've changed its' prev-pointer. */ if (!P_RIGHTMOST(ropaque)) { lastrdata->next = lastrdata + 1; @@ -1216,7 +1233,7 @@ _bt_findsplitloc(Relation rel, olddataitemstoleft = 0; goodenoughfound = false; maxoff = PageGetMaxOffsetNumber(page); - + for (offnum = P_FIRSTDATAKEY(opaque); offnum <= maxoff; offnum = OffsetNumberNext(offnum)) @@ -1234,7 +1251,7 @@ _bt_findsplitloc(Relation rel, olddataitemstoleft, itemsz); else if (offnum < newitemoff) - _bt_checksplitloc(&state, offnum, false, + _bt_checksplitloc(&state, offnum, false, olddataitemstoleft, itemsz); else { @@ -1285,11 +1302,11 @@ _bt_findsplitloc(Relation rel, * items go to the left page and only the new item goes to the right page. * In that case, firstoldonrightsz is not used. * - * olddataitemstoleft is the total size of all old items to the left of - * firstoldonright. + * olddataitemstoleft is the total size of all old items to the left of + * firstoldonright. */ static void -_bt_checksplitloc(FindSplitData *state, +_bt_checksplitloc(FindSplitData *state, OffsetNumber firstoldonright, bool newitemonleft, int olddataitemstoleft, @@ -1311,7 +1328,7 @@ _bt_checksplitloc(FindSplitData *state, /* Account for all the old tuples */ leftfree = state->leftspace - olddataitemstoleft; - rightfree = state->rightspace - + rightfree = state->rightspace - (state->olddataitemstotal - olddataitemstoleft); /* @@ -1854,7 +1871,7 @@ _bt_vacuum_one_page(Relation rel, Buffer buffer) BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page); /* - * Scan over all items to see which ones need to be deleted + * Scan over all items to see which ones need to be deleted * according to LP_DELETE flags. */ minoff = P_FIRSTDATAKEY(opaque); |