Hi, Justin! Thank you for revising documentation patch.
On Mon, May 7, 2018 at 7:55 PM, Justin Pryzby <pry...@telsasoft.com> wrote: > On Mon, May 07, 2018 at 07:26:25PM +0300, Alexander Korotkov wrote: > > Hi! > > > > I've revised docs and comments, and also made some fixes in the code. > > See the attached patchset. > > > > * 0004-btree-cleanup-docs-comments-fixes.patch > > Documentation and comment improvements from Justin Pryzby > > revised by me. > > 2nd iteration: > > diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml > index eabe2a9235..785ecf922a 100644 > --- a/doc/src/sgml/config.sgml > +++ b/doc/src/sgml/config.sgml > @@ -1893,15 +1893,35 @@ include_dir 'conf.d' > </term> > <listitem> > <para> > - When no tuples were deleted from the heap, B-tree indexes might > still > - be scanned during <command>VACUUM</command> cleanup stage by two > - reasons. The first reason is that B-tree index contains deleted > pages > - which can be recycled during cleanup. The second reason is that > B-tree > - index statistics is stalled. The criterion of stalled index > statistics > - is number of inserted tuples since previous statistics collection > - is greater than <varname>vacuum_cleanup_index_ > scale_factor</varname> > - fraction of total number of heap tuples. > + When no tuples were deleted from the heap, B-tree indexes are > still > + scanned during <command>VACUUM</command> cleanup stage unless two > + conditions are met: the index contains no deleted pages which can > be > + recycled during cleanup; and, the index statistics are not stale. > + In order to detect stale index statistics, number of total heap > tuples > should say: "THE number" > > + during previous statistics collection is memorized in the index > s/memorized/stored/ > > + meta-page. Once number number of inserted tuples since previous > Should say "Once the number of inserted tuples..." > > + statistics collection is more than > + <varname>vacuum_cleanup_index_scale_factor</varname> fraction of > + number of heap tuples memorized in the meta-page, index > statistics is > s/memorized/stored/ > > + considered to be stalled. Note, that number of heap tuples is > written > "THE number" > s/stalled/stale/ > > + to the meta-page at the first time when no dead tuples are found > remove "at" > > + during <command>VACUUM</command> cycle. Thus, skip of B-tree > index > I think should say: "Thus, skipping of the B-tree index scan" > > + scan during cleanup stage is only possible in second and > subsequent > s/in/when/ > > + <para> > + Zero value of <varname>vacuum_cleanup_index_ > scale_factor</varname> > I would say "A zero value of ..." > I've applied all the changes you suggested. Please, find it in the attached patchset. ------ Alexander Korotkov Postgres Professional: http://www.postgrespro.com The Russian Postgres Company
0001-vacuum-cleanup-index-scale-factor-user-set-2.patch
Description: Binary data
0002-vacuum-cleanup-index-scale-factor-tab-complete-2.patch
Description: Binary data
0003-btree-cleanup-condition-fix-2.patch
Description: Binary data
0004-btree-cleanup-docs-comments-fixes-2.patch
Description: Binary data
