Remove dedicated B-tree root-split record types.

Since commit 40dae7ec53, which changed the way b-tree page splitting
works, there has been no difference in the handling of root, and non-root
split WAL records. We don't need to distinguish them anymore

If you're worried about the loss of debugging information, note that
usually a root split record will normally be followed by a WAL record to
create the new root page. The root page will also have the BTP_ROOT flag
set on the page itself, and there is a pointer to it from the metapage.

Author: Aleksander Alekseev
Discussion: https://www.postgresql.org/message-id/20170406122116.GA11081@e733.localdomain
This commit is contained in:
Heikki Linnakangas 2017-08-16 12:16:18 +03:00
parent 77d05706be
commit 0c504a80cf
4 changed files with 5 additions and 26 deletions

View File

@ -980,7 +980,6 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
rightoff;
OffsetNumber maxoff;
OffsetNumber i;
bool isroot;
bool isleaf;
/* Acquire a new page to split into */
@ -1019,7 +1018,6 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
lopaque = (BTPageOpaque) PageGetSpecialPointer(leftpage);
ropaque = (BTPageOpaque) PageGetSpecialPointer(rightpage);
isroot = P_ISROOT(oopaque);
isleaf = P_ISLEAF(oopaque);
/* if we're splitting this page, it won't be the root when we're done */
@ -1330,11 +1328,7 @@ _bt_split(Relation rel, Buffer buf, Buffer cbuf, OffsetNumber firstright,
(char *) rightpage + ((PageHeader) rightpage)->pd_upper,
((PageHeader) rightpage)->pd_special - ((PageHeader) rightpage)->pd_upper);
if (isroot)
xlinfo = newitemonleft ? XLOG_BTREE_SPLIT_L_ROOT : XLOG_BTREE_SPLIT_R_ROOT;
else
xlinfo = newitemonleft ? XLOG_BTREE_SPLIT_L : XLOG_BTREE_SPLIT_R;
xlinfo = newitemonleft ? XLOG_BTREE_SPLIT_L : XLOG_BTREE_SPLIT_R;
recptr = XLogInsert(RM_BTREE_ID, xlinfo);
PageSetLSN(origpage, recptr);

View File

@ -193,7 +193,7 @@ btree_xlog_insert(bool isleaf, bool ismeta, XLogReaderState *record)
}
static void
btree_xlog_split(bool onleft, bool isroot, XLogReaderState *record)
btree_xlog_split(bool onleft, XLogReaderState *record)
{
XLogRecPtr lsn = record->EndRecPtr;
xl_btree_split *xlrec = (xl_btree_split *) XLogRecGetData(record);
@ -996,16 +996,10 @@ btree_redo(XLogReaderState *record)
btree_xlog_insert(false, true, record);
break;
case XLOG_BTREE_SPLIT_L:
btree_xlog_split(true, false, record);
btree_xlog_split(true, record);
break;
case XLOG_BTREE_SPLIT_R:
btree_xlog_split(false, false, record);
break;
case XLOG_BTREE_SPLIT_L_ROOT:
btree_xlog_split(true, true, record);
break;
case XLOG_BTREE_SPLIT_R_ROOT:
btree_xlog_split(false, true, record);
btree_xlog_split(false, record);
break;
case XLOG_BTREE_VACUUM:
btree_xlog_vacuum(record);

View File

@ -35,8 +35,6 @@ btree_desc(StringInfo buf, XLogReaderState *record)
}
case XLOG_BTREE_SPLIT_L:
case XLOG_BTREE_SPLIT_R:
case XLOG_BTREE_SPLIT_L_ROOT:
case XLOG_BTREE_SPLIT_R_ROOT:
{
xl_btree_split *xlrec = (xl_btree_split *) rec;
@ -121,12 +119,6 @@ btree_identify(uint8 info)
case XLOG_BTREE_SPLIT_R:
id = "SPLIT_R";
break;
case XLOG_BTREE_SPLIT_L_ROOT:
id = "SPLIT_L_ROOT";
break;
case XLOG_BTREE_SPLIT_R_ROOT:
id = "SPLIT_R_ROOT";
break;
case XLOG_BTREE_VACUUM:
id = "VACUUM";
break;

View File

@ -28,8 +28,7 @@
#define XLOG_BTREE_INSERT_META 0x20 /* same, plus update metapage */
#define XLOG_BTREE_SPLIT_L 0x30 /* add index tuple with split */
#define XLOG_BTREE_SPLIT_R 0x40 /* as above, new item on right */
#define XLOG_BTREE_SPLIT_L_ROOT 0x50 /* add tuple with split of root */
#define XLOG_BTREE_SPLIT_R_ROOT 0x60 /* as above, new item on right */
/* 0x50 and 0x60 are unused */
#define XLOG_BTREE_DELETE 0x70 /* delete leaf index tuples for a page */
#define XLOG_BTREE_UNLINK_PAGE 0x80 /* delete a half-dead page */
#define XLOG_BTREE_UNLINK_PAGE_META 0x90 /* same, and update metapage */