optimization (can I move pgsql_tmp)? - Mailing list pgsql-general
From | Ozz Nixon |
---|---|
Subject | optimization (can I move pgsql_tmp)? |
Date | |
Msg-id | B840BB82-FC53-4ADF-9077-4450D35E905D@gmail.com Whole thread Raw |
In response to | Re: pg_dump --compress error (Alvaro Herrera <alvherre@commandprompt.com>) |
Responses |
Re: optimization (can I move pgsql_tmp)?
Re: optimization (can I move pgsql_tmp)? |
List | pgsql-general |
Good after everyone, We are experiencing some performance issues on a table with 7 fields, 8,800,000 rows. During some exercises, one thingI noticed is I need to change the configuration of the system to house pgsql_tmp on a host partition instead of thedrive array... that will get me a little more speed... is this controlled via a .conf file or pgamin? Optimization questions: When is pgsql_tmp used? (Right now as I am creating indexes by hand, I see it grow for about 10 minutes): du -h /mnt/data/base/ 5.1M /mnt/data/base/1 5.1M /mnt/data/base/11563 4.0G /mnt/data/base/11564 8.9M /mnt/data/base/16395 586M /mnt/data/base/pgsql_tmp During the create index - communications in general to the drive array is "consumed". Before I keep experimenting and making things worse, I will ask - what indexes should I have to make this query better- or how does on debug when they find a query is taking too long??? STRUCTURE: quer.SQL.Add('create table '+DBTags+' ('); quer.SQL.Add(' pagename '+SQL_TITLE+'(100) not null,'); quer.SQL.Add(' tagword '+SQL_TITLE+'(15) not null,'); quer.SQL.Add(' soundex2 '+SQL_TITLE+'(4) not null,'); quer.SQL.Add(' metaphone '+SQL_TITLE+'(15) not null,'); quer.SQL.Add(' metaphone2 '+SQL_TITLE+'(22) not null,'); quer.SQL.Add(' carverphone '+SQL_TITLE+'(22) not null,'); quer.SQL.Add(' instances '+SQL_INT32+' not null,'); if SQL_NAME_PRIMARY_KEYS then quer.SQL.Add(' constraint '+DBTags+'_PK'); quer.SQL.Add(' primary key(pagename, tagword, instances)'); WAS 18 seconds with just the primary key, so I tried: create index tags1 on allwikitags(tagword) -- after still 18 seconds Then I tried: create index tags6 on allwikitags(tagword,instances desc, pagename) -- after now 32 seconds My Query: select pagename,tagword,instances from allwikitags where tagword in ('journey','journeys','journeyes','journeyd','journeyed','journeyly','journeyy','journeyth','journeydom','journeying','journeyize','journeyion','journeyism','journeyized','journeyizes','journeyizing','journeyions','journeyists','journeyfulness','journeyise','journeyish','journeyist','journeyful','journeytion','journeyless','journeyable','journeyfull','journeyious','journeylike','journeyment','journeyness') or soundex2 in ('J650') or metaphone in ('jrny') or metaphone2 in ('JRN') group by pagename,tagword,instances order by tagword,instances desc,pagename Thanks, Ozz
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