pg.ddx.io  pgsql-hackers@postgresql.org mailing list archive  

help / color / mirror / Atom feed
From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
To: Alexander Korotkov <aekorotkov@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: WIP: Fast GiST index build
Date: Thu, 11 Aug 2011 09:21:17 +0300
Message-ID: <4E4374DD.3000003@enterprisedb.com> (raw)
In-Reply-To: <CAPpHfdunxCQ-FU=eNHRKqgmw5wbXHOdj+28X_WqsZxU9r2X21w@mail.gmail.com>
References: <BANLkTikgOQ1+r=A9b08szNTeEWsk-cNMMg@mail.gmail.com>
	<CAPpHfdvoOh78ycX3eRePTS29635pHCSTfLdFDzHZhxTKsggCuQ@mail.gmail.com>
	<4E2DBB60.80604@enterprisedb.com>
	<4E2EF83A.8000304@enterprisedb.com>
	<CAPpHfdso-oOo4+3r9yBn=PATz3BC4z4cxK9Ew8tFRT1MkVVoiA@mail.gmail.com>
	<4E31D03D.70206@enterprisedb.com>
	<CAPpHfdtmgwOjNr7J15eCe6sXrtmq_c_52oNh-=D934SKekoGxg@mail.gmail.com>
	<CAPpHfdv=HQDmUGTARKjH+AiHMDpXa+8+WwuqjUSfZnVdC-LJbQ@mail.gmail.com>
	<CAPpHfduAhSNo8LHMPj_pqQ_2W6ZDPzdQBPzHbnpqaKz6kf4nrw@mail.gmail.com>
	<4E3977D8.1020506@enterprisedb.com>
	<CAPpHfducs8Ussw+t8iP3WS3ZTuX2J-77FOY=jAZUg-K6AuOC0g@mail.gmail.com>
	<CAPpHfdusd_b_dtvNY2uuJict6=VEUTGAS8ELXGck=o=kOdMnOw@mail.gmail.com>
	<4E3FAB1D.1060105@enterprisedb.com>
	<CAPpHfdsovwbgs30TojJc_zDsc+0ghapm+-AALfP58UaHiYjr2A@mail.gmail.com>
	<CAPpHfdvi5WZKdRD+s60R+pdm8dLczRQ5_RYt4L8OA_bhorPjpg@mail.gmail.com>
	<CAPpHfdunxCQ-FU=eNHRKqgmw5wbXHOdj+28X_WqsZxU9r2X21w@mail.gmail.com>

Split of an internal node works like this:

1. Gather all the existing tuples on the page, plus the new tuple being 
inserted.
2. Call picksplit on the tuples, to divide them into pages
3. Go through all tuples on the buffer associated with the page, and 
divide them into buffers on the new pages. This is done by calling 
penalty function on each buffered tuple.

I wonder if it would be better for index quality to pass the buffered 
tuples to picksplit in the 2nd step, so that they too can affect the 
split decision. Maybe it doesn't make much difference in practice..

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com



view thread (114+ messages)  latest in thread

Message-ID: <4E4374DD.3000003@enterprisedb.com>
Permalink:  ../4E4374DD.3000003@enterprisedb.com/
Also on:    postgresql.org/message-id/4E4374DD.3000003@enterprisedb.com

 · 

reply
Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-hackers@postgresql.org
  Cc: heikki.linnakangas@enterprisedb.com, aekorotkov@gmail.com
  Subject: Re: WIP: Fast GiST index build
  In-Reply-To: <4E4374DD.3000003@enterprisedb.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox