On 2018-11-29 14:27:50 +0100, Dmitry Dolgov wrote: > > On Fri, Sep 21, 2018 at 5:52 AM Andrey Lepikhov <a.lepik...@postgrespro.ru> > > wrote: > > > > The v6 version of quick vacuum, which utilizes the amtargetdelete() > > interface for retail indextuple deletion. > > Now it is more simple and laconic. > > It must be applied after Retail-IndexTuple-Deletion-Access-Method.patch. > > > > BENCHMARKS: > > ----------- > > > > Initial script: > > pgbench -i -s $scale # initial DB generation > > "CREATE INDEX pgbench_accounts_ext ON public.pgbench_accounts USING > > btree (abalance);" # additional index > > > > Comparison with lazy vacuum: > > > > script: > > "DELETE FROM pgbench_accounts WHERE (random() < $factor);" # delete a > > part of tuples for cleaning strategies comparison > > "VACUUM pgbench_accounts;" # check time of vacuum process by bash 'date > > +%s%N | cut -b1-13' command > > > > Results: > > | $scale=10 | $scale=100 | > > $factor| QVAC | LVAC | QVAC | LVAC | > > 1E-6 | - | - | 284 | 979 | > > 1E-5 | 78 | 144 | 288 | 1423 | > > 1E-4 | 72 | 280 | 388 | 3304 | > > 1E-3 | 189 | 609 | 2294 | 6029 | > > 1E-2 | 443 | 783 | 54232| 67884| > > 1E-1 | 1593 | 1237 | 83092| 86104| > > > > where QVAC - forced use of quick vacuum; LVAC - use lazy vacuum for > > index cleanup. $factor corresponds a number of vacuumed tuples. For > > example, $scale=10, $factor=1E-1 -> 100000 tuples vacuumed. Time > > measured in ms. > > > > So, quick strategy can be used in a vacuum process effectively up to > > 1-2% of DEAD tuples in a relation. > > Hi, > > Unfortunately, this patch doesn't compile anymore: > > index.c: In function ‘htid2IndexDatum’: > index.c:4172:2: error: too few arguments to function > ‘MakeSingleTupleTableSlot’ > TupleTableSlot *slot = MakeSingleTupleTableSlot(RelationGetDescr(hrel)); > ^ > > Also I'm a bit confused about the current status of collaboration between this > patch and [1], one is tightly depends on another or not? Does it makes sense > to have only one corresponding CF item then? For now I'll move this one to > the next CF. > > [1]: > https://www.postgresql.org/message-id/flat/CAH2-WzkVb0Kom%3DR%2B88fDFb%3DJSxZMFvbHVC6Mn9LJ2n%3DX%3DkS-Uw%40mail.gmail.com
Given this patch has not been updated since Dmitry's message above, I'm marking this as returned with feedback. Greetings, Andres Freund
