mirrors/postgres
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Correct obsolete nbtree recovery comments.

Browse Source 
Commit 40dae7ec537, which made the handling of interrupted nbtree page
splits more robust, removed an nbtree-specific end-of-recovery cleanup
step.  This meant that it was no longer possible to complete an
interrupted page split during recovery.  However, a reference to
recovery as a reason for using a NULL stack while inserting into a
parent page was missed.  Remove the reference.

Remove a similar obsolete reference to recovery that was introduced much
more recently, as part of the btree fastpath optimization enhancement
that made it into Postgres 11 (commit 2b272734, and follow-up commits).

Backpatch: 11-, where the fastpath optimization was introduced.
This commit is contained in:
Peter Geoghegan 2018-12-18 16:59:50 -08:00
parent 3cab54878d
commit 60f3cc9553
1 changed files with 6 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/access/nbtree/nbtinsert.c
View File

@ -876,10 +876,10 @@ _bt_insertonpg(Relation rel,
* all the required conditions, including the fact that this page has * all the required conditions, including the fact that this page has
* enough freespace. Note that this routine can in theory deal with * enough freespace. Note that this routine can in theory deal with
* the situation where a NULL stack pointer is passed (that's what * the situation where a NULL stack pointer is passed (that's what
* would happen if the fastpath is taken), like it does during crash * would happen if the fastpath is taken). But that path is much
* recovery. But that path is much slower, defeating the very purpose * slower, defeating the very purpose of the optimization. The
* of the optimization. The following assertion should protect us * following assertion should protect us from any future code changes
* from any future code changes that invalidate those assumptions. * that invalidate those assumptions.
* *
* Note that whenever we fail to take the fastpath, we clear the * Note that whenever we fail to take the fastpath, we clear the
* cached block. Checking for a valid cached block at this point is * cached block. Checking for a valid cached block at this point is
@ -1807,8 +1807,8 @@ _bt_checksplitloc(FindSplitData *state,
* and it'd be possible for some other process to try to split or delete * and it'd be possible for some other process to try to split or delete
* one of these pages, and get confused because it cannot find the downlink.) * one of these pages, and get confused because it cannot find the downlink.)
* *
* stack - stack showing how we got here. May be NULL in cases that don't * stack - stack showing how we got here. Will be NULL when splitting true
* have to be efficient (concurrent ROOT split, WAL recovery) * root, or during concurrent root split, where we can be inefficient
* is_root - we split the true root * is_root - we split the true root
* is_only - we split a page alone on its level (might have been fast root) * is_only - we split a page alone on its level (might have been fast root)
*/ */