threads listlengths 1 275 |
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[
{
"msg_contents": "Hi,\n\nI've been trying to spec a new server for my company's database for a\nfew weeks and one of the biggest problems I've had is trying to find\nmeaningful performance information about how PostgreSQL will perfom\nunder various disk configurations.\n\nBut, we have now taken the plunge and ... |
[
{
"msg_contents": "> > \tThere is also the fact that NTFS is a very slow filesystem, and\n> > Linux is\n> > a lot better than Windows for everything disk, caching and IO related.\n> Try\n> > to copy some files in NTFS and in ReiserFS...\n> \n> I'm not so sure I would agree with such a blanket generalization. I... |
[
{
"msg_contents": "I was just copying a database that was in UNICODE encoding into a new\ndb for some testing. I hand't realized it was UNICODE and when it hit\nsome funky chinese data (from some spam that came in...) it errored\nout with a string too long for a varchar(255).\n\nThe dump was created on PG 7.4.... |
[
{
"msg_contents": "Greetings,\n\nI have observed that in a dump/restore scenario the longest time is \nspent on index creation for larger tables, I have a suggestion of how \nthe performance could be improved thus reducing the time to recover \nfrom a crash. Not sure if this is possible but would definitely be ... |
[
{
"msg_contents": "I have been experimenting with the 'IPC::Shareable' module under the \nnative implementation of Perl 5 for OpenBSD 3.5. While it is not loaded \nby default it is a pure pure implementation.\n\nI have tested this module under two machines, one which used to run \nPostgreSQL and has a higher ... |
[
{
"msg_contents": "Sorry for crossposting, didn't know where to post.\n\nAny hint/help on this?!\n\ndb_postgres1=# truncate ref_v2_drs_valid_product ;\nERROR: expected both swapped tables to have TOAST tables\n\nI need to truncate this table, this is the first time I see this error.\n\nRegards,\nGuido\n\n",
... |
[
{
"msg_contents": "Ok, problem solved.\n\nA previous ALTER TABLE DROP COLUMN over this table was performed.\nBy some reason, truncate didn't work then. Would like to know why...it does not seems to be a very frequent problem, due to the fact I only found one chat on the mailing lists talking about this issue, a... |
[
{
"msg_contents": "-----BEGIN PGP SIGNED MESSAGE-----\nHash: SHA1\n\nI have a problem where I have the table format listed below. I have the \nprimary key tsyslog_id and the index built against it. However, when I \nselect a unique row, it will only ever do a seq scan even after I turn off \nall other types e... |
[
{
"msg_contents": "Hi. I hope I'm not asking a too trivial question here...\n\nI'm having trouble with a (quite big) query, and can't find a way to make it \nfaster.\n\nHere is the information :\n\nTables :\n============================\nsces_vte -> 2753539 rows\nsces_art -> 602327\nsces_fsf -> 8126\nsces_frc -... |
[
{
"msg_contents": "What would be performance of pgSQL text search vs MySQL vs Lucene (flat \nfile) for a 2 terabyte db?\nthanks for any comments.\n.V\n-- \nPlease post on Rich Internet Applications User Interface (RiA/SoA) \n<http://www.portalvu.com>\n",
"msg_date": "Thu, 09 Sep 2004 07:56:20 -0500",
"m... |
[
{
"msg_contents": "Hello,\n\nI'm tuning my PostgreSQL DB (7.3.4) and have come across a query that\ndoesn't use an index I created specially for it, and consequently takes\ncirca 2 seconds to run. :(\n\nThe ugly query looks like this (the important part is really at the\nvery end - order by piece):\n\nselect us... |
[
{
"msg_contents": "#postgresql on Freenode recommended I post this here.\n\nI'm seeing some odd behaviour with LIMIT. The query plans are included\nhere, as are the applicable table and index definitions. All table,\nindex, and query information can be found in a standard dbmail 1.2.6\ninstall, if anyone wants ... |
[
{
"msg_contents": "Hello,\n\nI saw a few mentions of 'effective_cache_size' parameter. Is this a\nnew PG 7.4 option? I have PG 7.3.4 and didn't see that parameter in my\npostgresql.conf.\n\nThanks,\nOtis\n\n",
"msg_date": "Fri, 10 Sep 2004 15:00:07 -0700 (PDT)",
"msg_from": "<ogjunk-pgjedan@yahoo.com>... |
[
{
"msg_contents": "Here's the query:\n\n---------------------------------------------------------------------------\nSELECT * FROM bv_reviews r, bv_votes v \nWHERE r.vote_id = v.vote_id \nAND v.book_id = 113\n---------------------------------------------------------------------------\n\nbv_votes has around 7000... |
[
{
"msg_contents": "Hi all,\nI had a difficult time deciding which list to post\nthis to, so please forgive me if this list doesn't\nperfectly match my questions. My decision will not\nsolely be based on performance, but it is the primary\nconcern. I would be very appreciative if you all\ncould comment on my t... |
[
{
"msg_contents": "Hi, I have downloaded the new postgresql (version 8.0 beta2) and I was\nwondering what performance features I can take advantage of before I start\nto dump my 3/4 terrabyte database into the new format. More specifically\nI am interested in tablespaces--what exactly is this feature, some sor... |
[
{
"msg_contents": "--- Herv���<inputPiedvache <herve@elma.fr> wrote:\n\n> George,\n> \n> I have well read many pages about this subject ... but I have not found any \n> thing for the moment to really help me ...\n> What can I do to optimize my PostgreSQL configuration for a special use of \n> Tsearch2 ...\n> I'... |
[
{
"msg_contents": "Hi i have four sample tables ename, esal, edoj and esum\nAll of them have 1000000 records. Im running the following\nquery : select ename.eid, name, sal, doj, summary from\nename,esal,edoj,esum where ename.eid=esal.eid and ename.eid=edoj.eid\nand ename.eid=esum.eid. Its a join of all four tab... |
[
{
"msg_contents": "Hi, I'd like to help with the topic in the Subject: line. It seems to be a \nTODO item. I've reviewed some threads discussing the matter, so I hope I've \nacquired enough history concerning it. I've taken an initial swipe at \nfiguring out how to optimize sync'ing methods. It's b... |
[
{
"msg_contents": "\nHi All,\n\nI am having a performance problem extracting a large volume of data from\nPostgres 7.4.2, and was wondering if there was a more cunning way to get\nthe data out of the DB...\n\nThis isn't a performance problem with any particular PgSQL operation,\nits more a strategy for getting ... |
[
{
"msg_contents": "Hi, I have downloaded the new postgresql (version 8.0 beta2) and I was\nwondering what performance features I can take advantage of before I start\nto dump my 3/4 terrabyte database into the new database. More \nspecifically\nI am interested in tablespaces--what exactly is this feature, some... |
[
{
"msg_contents": "Does postgres cache the entire result set before it begins returning\ndata to the client?\n\nI have a table with ~8 million rows and I am executing a query which\nshould return about ~800,000 rows. The problem is that as soon as I\nexecute the query it absolutely kills my machine and begins s... |
[
{
"msg_contents": "Hi,\n\nI found bulk-insert to perform very slow, when compared to MySQL / Oracle. All inserts were done in 1 transaction. However, mitigating factors here were:\n- Application was a .Net application using ODBC drivers\n- PostgreSQL 7.3 running on CYGWIN with cygipc daemon\n- Probably very bad... |
[
{
"msg_contents": "\n-----Original Message-----\nFrom: pgsql-performance-owner@postgresql.org [mailto:pgsql-performance-owner@postgresql.org]On Behalf Of Steinar H. Gunderson\nSent: Tuesday, September 14, 2004 3:33 PM\nTo: PostgreSQL Performance List\nSubject: Re: [PERFORM] Data Warehouse Reevaluation - MySQL v... |
[
{
"msg_contents": ">From: \"Harald Lau (Sector-X)\" <harald@sector-x.de>\n...\n> > From: \"Mischa Sandberg\" <ischamay.andbergsay@activestateway.com>\n> >\n> > > If your company is currently happy with MySQL, there probably are\n> > > other (nontechnical) reasons to stick with it. I'm impressed that\n> > > you'... |
[
{
"msg_contents": "Hi,\n\n-----Original Message-----\nFrom: pgsql-performance-owner@postgresql.org [mailto:pgsql-performance-owner@postgresql.org]On Behalf Of Michael Kleiser\nSent: Tuesday, September 14, 2004 4:23 PM\nTo: Leeuw van der, Tim\nCc: Steinar H. Gunderson; PostgreSQL Performance List\nSubject: Re: [... |
[
{
"msg_contents": "\nJoe Conway <mail@joeconway.com> wrote on 15.09.2004, 06:30:24:\n> Chris Browne wrote:\n> > Might we set up the view as:\n> > \n> > create view combination_of_logs as\n> > select * from table_1 where txn_date between 'this' and 'that' \n> > union all\n> > select * from table_2 where t... |
[
{
"msg_contents": "Why would postgres use a different query plan for declared cursors than \nwithout?\n\nI have a relatively simple query that takes about 150ms using explain \nanalyze. However, when I wrap the same query in a declared cursor \nstatement, the subsequent fetch statement takes almost 30seconds. F... |
[
{
"msg_contents": "\nChris Browne <cbbrowne@acm.org> wrote on 15.09.2004, 04:34:53:\n> simon@2ndquadrant.com (\"Simon Riggs\") writes:\n> > Well, its fairly straightforward to auto-generate the UNION ALL view,\nand\n> > important as well, since it needs to be re-specified each time a new\n> > partition is loade... |
[
{
"msg_contents": "I'm working on a dating/personals/match-making site, that has used many \ndifferent methods of \"match-making\", that all seem to be very slow. One I am \nattempting now that seems to be an efficient method of storage, but not the \nbest for indexing, is using bitwise operators to compare one... |
[
{
"msg_contents": "Ricardo,\n\nHello. I've moved your query to a more appropriate mailing list; on \nPERFORMANCE we discuss RAID all the time. If you don't mind wading through a \nhost of opinions, you'll get plenty here. I've also cc'd our Brazillian \nPostgreSQL community.\n\nEveryone, please note that Ri... |
[
{
"msg_contents": "Our product (Sophos PureMessage) runs on a Postgres database.\n\nSome of our Solaris customers have Oracle licenses, and they've \ncommented on the performance difference between Oracle and Postgresql\non such boxes. In-house, we've noticed the 2:1 (sometimes 5:1)\nperformance difference in i... |
[
{
"msg_contents": "Hi,\n\nI'm using PostgreSQL 7.4 on a table with ~700.000 rows looking like this:\n\n Table \"public.enkeltsalg\"\n Column | Type | Modifiers \n------------+--------------------------+--------... |
[
{
"msg_contents": "A recent comment on this (or perhaps another?) mailing list about Sun boxen\nand the directio mount option has prompted me to read about O_DIRECT on the\nopen() manpage.\n\nHas anybody tried this option? Ever taken any performance measurements?\nI assume the way postgres manages its buffer me... |
[
{
"msg_contents": "Hello.\nCouple of questions:\n\n\n- Q1: Today I decided to do a vacuum full verbose analyze on a large table that has been giving me slow performance. And then I did it again. I noticed that after each run the values in my indexes and estimate row version changed. What really got me wonder... |
[
{
"msg_contents": "Hi all,\n\nI searched list archives, but did not found anything about HT of Pentium \n4/Xeon processors. I wonder if hyperthreading can boost or decrease \nperformance. AFAIK for other commercial servers (msssql, oracle) official \ndocuments state something like \"faster, but not always, so p... |
[
{
"msg_contents": "-----BEGIN PGP SIGNED MESSAGE-----\nHash: SHA1\n\nHi all,\nI'm having performance degradation with a view upgrading from\n7.3 to 7.4, the view is a not so complex, one of his field\nis the result from a function.\nIf I remove the function ( or I use a void function ) the 7.4\nout perform the ... |
[
{
"msg_contents": "I couldn't find anything in the docs or in the mailing list on this,\nbut it is something that Oracle appears to do as does MySQL.\nThe idea, I believe, is to do a quick (hash) string lookup of the\nquery and if it's exactly the same as another query that has been done\nrecently to re-use the... |
[
{
"msg_contents": "\n\n\n\nGentlefolk,\n\nI'm not sure if this is the proper forum for this question, and it might\nhave been answered in a previous thread, but I'm new to PostgreSQL and the\nresearch I did in the archives did not turn up anything addressing this\nissue. Please direct me to the proper forum is... |
[
{
"msg_contents": "\n\n\n\nI just realized in my haste to send this email out I provided the wrong\ntable in my example. Below is the same email, but with\nvsa.dtbl_logged_event_20040922 substituted for vsa.tbl_sad_event.\n\nSorry for the inconvenience.\n\n--- Steve\n\n\nGentlefolk,\n\nI'm not sure if this is ... |
[
{
"msg_contents": "Hello,\n\n \n\nI'll be moving a DB from internal RAID-10 SCSI storage to an EMC CX300\nFC RAID-10 LUN, bound to the host. I've setup a test host machine and a\ntest LUN. The /var/lib/pgsql/data folder is sym-linked to a partition on\nthe LUN. \n\n \n\nOther than the shared_buffers, effective ... |
[
{
"msg_contents": "Scott: \n\nWe have seen similar issues when we have had massive load on our web\nserver. My determination was that simply the act of spawning and\nstopping postgres sessions was very heavy on the box, and by\nimplementing connection pooling (sqlrelay), we got much higher\nthroughput, and bett... |
[
{
"msg_contents": "I believe 1/0 or 1+0 is aka RAID-10. CX300 doesn't support 0+1.\r\n \r\nSo far i am aware of two things, the cache page size is 8KB (can be increased or decreased), and the stripe element size of 128 sectors default.\r\n \r\nThanks,\r\nAnjan\r\n\r\n\t-----Original Message----- \r\n\tFrom: Mr ... |
[
{
"msg_contents": "My database was converted from MySQL a while back and has maintained all \nof the indexes which were previously used. Tt the time however, there \nwere limitations on the way PostgreSQL handled the indexes compared to \nMySQL.\n\nMeaning that under MySQL, it would make use of a multi-column... |
[
{
"msg_contents": "\nIf you have set up the postgres instance to write stats, the tables pg_stat_user_indexes, pg_statio_all_indexes and so (use the \\dS option at the psql prompt to see these system tables); also check the pg_stat_user_tables table and similar beasts for information on total access, etc. Betwe... |
[
{
"msg_contents": "Hi,\n\nWe have been running PostgreSQL 7.3.4 on 64 bit MAC OS X G5 dual \nprocessors with 8GB of RAM for a while.\nLately, we realized that consistently only about 4GB of RAM is used \neven when CPUs have maxed out\nfor postgtres processes and pageouts starts to happen. Here is a \nportion o... |
[
{
"msg_contents": "I set nested_loop = off, which is why I have the high cost.\n\n@ is a postgis operator between 2 geomotries (both polygons). It's the @\noperator which is expensive. Is there a way to force a cheaper way of\ndoing that join?\n\n -> Nested Loop (cost=100001905.94..100001906.08 rows=1... |
[
{
"msg_contents": "\nIs everyone still building interactively? I'm looking for nice ways to \nautomate building on Windows without any human action required, as part \nof the buildfarm project. Ideas on how to do this nicely for Windows \nwould be appreciated. Can one run the MSys shell without it firing up an ... |
[
{
"msg_contents": "I finished the write-up I mentioned a few weeks ago.\n\nFeedback is welcome.\n\nThanks to everyone on this list and especially to all\nthe folks in IRC who helped me get up to speed on\nPostgreSQL in a very short period of time.\n\nI've already migrated one of the applications I\ncowrote wit... |
[
{
"msg_contents": "Hi all,\ndon't you think the best statistic target for a boolean\ncolumn is something like 2? Or in general the is useless\nhave a statistics target > data type cardinality ?\n\n\n\nRegards\nGaetano Mendola\n",
"msg_date": "Mon, 27 Sep 2004 20:09:46 +0200",
"msg_from": "Gaetano Mendo... |
[
{
"msg_contents": "\n> Gaetano,\n> \n> > don't you think the best statistic target for a boolean\n> > column is something like 2? Or in general the is useless\n> > have a statistics target > data type cardinality ?\n> \n> It depends, really, on the proportionality of the boolean values; if they're \n> about eq... |
[
{
"msg_contents": "Help?\n\nNormally, this query takes from 5 minutes to 2 hours to run. On this update, it's been running for more than 10 hours.\n\nCan it be helped?\n\nUPDATE obs_v\nSET mag = obs_v.imag + zp.zero_v + cg.color_v * (obs_v.imag - i.imag),\n use = true\nFROM color_groups AS cg, zero_pair AS ... |
[
{
"msg_contents": "Folks,\n\nI'm beginning a series of tests on OSDL's Scalable Test Platform in order to \ndetermine some recommended settings for many of the new PostgreSQL.conf \nparameters as well as pg_autovacuum. \n\nIs anyone else interested in helping me with this? \n\n-- \n--Josh\n\nJosh Berkus\... |
[
{
"msg_contents": "What is involved, rather what kind of help do you require? \n\nDan.\n\n-----Original Message-----\nFrom: pgsql-performance-owner@postgresql.org\n[mailto:pgsql-performance-owner@postgresql.org]On Behalf Of Josh Berkus\nSent: Tuesday, September 28, 2004 1:54 PM\nTo: pgsql-performance@postgresq... |
[
{
"msg_contents": "Hi,\n\nI have a query where I do not understand that the rows number that \nexplain analyze finds differs so much from what explain estimates (3rd \nnested loop estimates 1 row but in real it is 4222 rows). I did analyze \nthe tables (pgsql 7.4.1).\n\nHere is the query:\n\nexplain analyze\nSE... |
[
{
"msg_contents": "Dear Gurus,\n\nHere is this strange query that can't find the optimum plan unless I disable\nsome scan modes or change the costs.\n\n(A) is a 2x2.4GHz server with hw raid5 and v7.3.4 database. It chooses\nhashjoin.\n(B) is a 300MHz server with 7200rpm ide and v7.4.2 database. It chooses\nseqs... |
[
{
"msg_contents": "Hi all, a small question:\n\nI've got this table \"songs\" and an index on column artist. Since there's about\none distinct artist for every 10 rows, it would be nice if it could use this\nindex when counting artists. It doesn't however:\n\nlyrics=> EXPLAIN ANALYZE SELECT count(DISTINCT art... |
[
{
"msg_contents": "OK, I have a situation that might be a performance problem, a bug, or an\nunavoidable consequence of using prepared statements. The short version\nis that I am getting function executions for rows not returned in a\nresult set when they are in a prepared statement.\n\nIn other words, I have ... |
[
{
"msg_contents": "> Here's another workaround that may let you use a prepared statement:\n> \n> prepare ps(...) as\n> select f(c) from (select c from t where [expr] limit 1) as t1\n> \n> -Mike\n\nI was just exploring that. In fact, the problem is not limited to\nprepared statements...it's just that they are m... |
[
{
"msg_contents": "Sometimes when you click on a link on my site to access my postgres database\nit takes forever for it to connect. You can click this link and see how long\nit takes.\n <http://www.3idiots.com:8080/examples/jsp/movies/wantedlist.jsp>\nhttp://www.3idiots.com:8080/example.../wantedlist.jsp\n\nIt... |
[
{
"msg_contents": "Stephan Szabo wrote:\n> On Thu, 30 Sep 2004, Merlin Moncure wrote:\n> \n> > OK, I have a situation that might be a performance problem, a bug,\nor an\n> > unavoidable consequence of using prepared statements. The short\nversion\n> > is that I am getting function executions for rows not retur... |
[
{
"msg_contents": "\n\tTo save some time, let me start by saying\n\nPostgreSQL 7.4.3 on powerpc-apple-darwin7.4.0, compiled by GCC gcc \n(GCC) 3.3 20030304 (Apple Computer, Inc. build 1640)\n\n\tOK, now on to details...\n\n\tI'm trying to implement oracle style ``partitions'' in postgres. I've \nrun into my fi... |
[
{
"msg_contents": "Pg: 7.4.5\nRH 7.3\n8g Ram\n200 g drive space\nRAID0+1\nTables vacuum on a nightly basis\n\nThe following process below takes 8 hours to run on 90k records and I'm \nnot sure where to being to look for the bottleneck. This isn't the only \nupdating on this database that seems to take a long t... |
[
{
"msg_contents": "Okay, I've got two queries that I think the planner should reduce to be \nlogically equivalent but it's not happening. The example queries below have \nbeen simplified as much as possible while still producing the problem. \n\nWhat I'm trying to do is create a single prepared statement that c... |
[
{
"msg_contents": "Steve,\n\n> I'm used to performance tuning on a select-heavy database, but this\n> will have a very different impact on the system. Does anyone have any\n> experience with an update heavy system, and have any performance hints\n> or hardware suggestions?\n\nMinimal/no indexes on the table(s).... |
[
{
"msg_contents": "would the number of fields in a table significantly affect the\nsearch-query time?\n\n(meaning: less fields = much quicker response?)\n\nI have this database table of items with LOTS of properties per-item,\nthat takes a LONG time to search.\n\nSo as I was benchmarking it against SQLite, MySQ... |
[
{
"msg_contents": "Running a trivial query in v7.4.2 (installed with fedora core2) using\nEXPLAIN ANALYZE is taking considerably longer than just running the query\n(2mins vs 6 secs). I was using this query to quickly compare a couple of\nsystems after installing a faster disk.\n\nIs this sort of slowdown to be... |
[
{
"msg_contents": "All,\n\nI realize the excessive-context-switching-on-xeon issue has been \ndiscussed at length in the past, but I wanted to follow up and verify my \nconclusion from those discussions:\n\nOn a 2-way or 4-way Xeon box, there is no way to avoid excessive \n(30,000-60,000 per second) context swi... |
[
{
"msg_contents": "Hi,\n\n(pg_version 7.4.2, i do run vacuum analyze on the whole database frequently \nand just before executing statements below)\n\ni dont know if anyone can help me because i dont know really where the problem \nis, but i try. If any further information is needed i'll be glad to send.\n\nmy ... |
[
{
"msg_contents": "Hello!\n\nI'm using Postgres 7.4.5, sort_mem is 8192. Tables analyzed / vacuumed.\n\nHere's a function I'm using to get an age from the user's birthday:\n\nagey(date) -> SELECT date_part('year', age($1::timestamp))\n\n\nThe problem is, why do the plans differ so much between Q1 & Q3 below? So... |
[
{
"msg_contents": "please ignore if this goes through. They've been bouncing and I'm trying to\nfind out why.\n\n-m\n",
"msg_date": "Tue, 5 Oct 2004 23:24:46 -0400",
"msg_from": "Max Baker <max@warped.org>",
"msg_from_op": true,
"msg_subject": "test post"
}
] |
[
{
"msg_contents": "postgres=# explain ANALYZE select * from test where today < '2004-01-01';\n QUERY PLAN\n----------------------------------------------------------------------------------------------------\n Seq Scan on test (cost=0.00..19.51 rows=334 width=44) (ac... |
[
{
"msg_contents": "Hi,\n\nI'm using Postgres 7.4.5. Tables are analyzed & vacuumed.\n\nI am wondering why postgresql never uses an index on queries of the type\n'select distinct ...' while e.g. mysql uses the index on the same query.\nSee the following explains:\n\n\npostgresql:\n\nexplain analyze select distin... |
[
{
"msg_contents": "Hi,\n\nI'm looking for the statistic of memory, CPU, filesystem access while \nexecuting some regular SQL query, and I want to compare them to\nsame kind of results while executing a cursor function.\n\nThe stat collector give me good results (sequencial scans , acceded \ntuple .....) fo... |
[
{
"msg_contents": "Hello,\n We recently upgraded os from rh 7.2 (2.4 kernel) to Suse 9.1 (2.6 \nkernel), and psql from 7.3.4 to 7.4.2\n\n One of the quirks I've noticed is how the queries don't always have the \nsame explain plans on the new psql... but that's a different email I think.\n\n My main questi... |
[
{
"msg_contents": "Hi guys,\n\n I just discussed about my problem on IRC. I am building a Web usage \nmining system based on Linux, PostgreSQL and C++ made up of an OLTP \ndatabase which feeds several and multi-purpose data warehouses about users' \nbehaviour on HTTP servers.\n\n I modelled every warehous... |
[
{
"msg_contents": "I have a large table with a column:\nids integer[] not null\n\nmost of these entries (over 95%) contain only one array element, some\ncan contain up to 10 array elements. seqscan is naturally slow. GIST\non int_array works nice, but GIST isn't exactly a speed daemon when it\ncomes to updati... |
[
{
"msg_contents": "\nI just ran a COPY of a million records several times, and each time I\nran it it ran apparently exponentially slower. If I do an insert of\n10 million records, even with 2 indexes (same table) it doesn't appear\nto slow down at all. Any ideas?\n\n- Mike H.\n\n(I apologize for the ^Hs)\n\n... |
[
{
"msg_contents": "\nJosh Berkus <josh@agliodbs.com> wrote on 08.10.2004, 07:53:26:\n> \n> > It's not so much that they are necessarily inefficient as that they\n> > constrain the planner's freedom of action. You need to think a lot more\n> > carefully about the order of joining than when you use inner joins.\... |
[
{
"msg_contents": "Hi,\n\n I have a problem with the below query, when i do explain on the \nbelow query on my live database it doesnt use any index specified on the \ntables and does seq scan on the table which is 400k records. But if i \ncopy the same table onto a different database on a different machin... |
[
{
"msg_contents": "I'm looking at one of my standard queries and have encountered some strange \nperformance problems.\n\nThe query below is to search for vacant staff member date/time slots given a series of \ntarget date/times. The data contained in the booking_plan/staff_booking tables contain \nthe existing... |
[
{
"msg_contents": "Folks,\n\nI'm hoping that some of you can shed some light on this.\n\nI've been trying to peg the \"sweet spot\" for shared memory using OSDL's \nequipment. With Jan's new ARC patch, I was expecting that the desired \namount of shared_buffers to be greatly increased. This has not turned ou... |
[
{
"msg_contents": "Hi all,\nI'm wondering if setting the $PG_DATA directory\nas synchronous directory in order to make a crash\nevent more safe will penalyze the performances.\n\nIf you run a kernel 2.6 the command is:\n\nchattr +S $PG_DATA\n\n\n\nRegards\nGaetano Mendola\n\n\n\n",
"msg_date": "Sun, 10 Oct ... |
[
{
"msg_contents": "I've been wondering...\n\nSuppose we have two tables\nCREATE TABLE messages (\n message_id serial PRIMARY KEY,\n message text NOT NULL\n);\nCREATE TABLE entries (\n entry_id serial PRIMARY KEY,\n message_id integer NOT NULL REFERENCES messages\n);\n\nAnd we have a join:\nSELECT entry_id... |
[
{
"msg_contents": "Is there a tutorial or reference to the different terms that appear on the \nexplain output?\n\n\nItems such as \"Nested Loop\", \"Hash\"..\n\nAlso is there a way to easily tell which of two explains is \"worse\". \nExample I am running a query with \"set enable_seqscan to off;\" and i see \n... |
[
{
"msg_contents": "Hi guys,\n\n please consider this scenario. I have this table:\n\nCREATE TABLE ip2location (\n ip_address_from BIGINT NOT NULL,\n ip_address_to BIGINT NOT NULL,\n id_location BIGINT NOT NULL,\n PRIMARY KEY (ip_address_from, ip_address_to)\n);\n\nI created a cluster on its p... |
[
{
"msg_contents": "Folks,\n\nIn order to have a place for scripts, graphs, results, etc., I've started the \nTestPerf project on pgFoundry:\nhttp://pgfoundry.org/projects/testperf/\n\nIf you are interested in doing performance testing for PostgreSQL, please join \nthe mailing list for the project. I could cer... |
[
{
"msg_contents": "Hello\n\nI am doing a comparison between MySQL and PostgreSQL.\n\nIn the MySQL manual it says that MySQL performs best with Linux 2.4 with\nReiserFS on x86. Can anyone official, or in the know, give similar\ninformation regarding PostgreSQL?\n\nAlso, any links to benchmarking tests available ... |
[
{
"msg_contents": "Hi,\n\nI sent this to general earlier but I was redirected to performance.\n\nThe query have been running ok for quite some time, but after I did a\nvacuum on the database, it's very very slow. This IN-query is only 2\nids. Before the problem that in was a subselect-query returning around\n6-... |
[
{
"msg_contents": "All,\n\tMy company (Chariot Solutions) is sponsoring a day of free\nPostgreSQL training by Bruce Momjian (one of the core PostgreSQL\ndevelopers). The day is split into 2 sessions (plus a Q&A session):\n\n * Mastering PostgreSQL Administration\n * PostgreSQL Performance Tuning\n\n\tRegistrat... |
[
{
"msg_contents": "Sent this to wrong list.\n\n-------- Forwarded Message --------\nFrom: Robin Ericsson <robin.ericsson@profecta.se>\nTo: pgsql-general@postgresql.org\nSubject: Re: [GENERAL] [PERFORM] query problem\nDate: Wed, 13 Oct 2004 18:27:20 +0200\nOn Wed, 2004-10-13 at 18:01 +0200, Robin Ericsson wrote:... |
[
{
"msg_contents": "Hi guys,\n\nI have some DBT-3 (decision support) results using Gavin's original\nfutex patch fix. It's on out 8-way Pentium III Xeon systems\nin our STP environment. Definitely see some overall throughput\nperformance on the tests, about 15% increase, but not change with\nrespect to the num... |
[
{
"msg_contents": "Hi,\n\nWe are experiencing slow performance on 8 Beta 2 Dev3 on Win32 and are\ntrying to determine why. Any info is appreciated.\n\nWe have a Web Server and a DB server both running Win2KServer with all\nservice packs and critical updates.\n\nAn ASP page on the Web Server hits the DB Server w... |
[
{
"msg_contents": ">Hi,\n>\n>We are experiencing slow performance on 8 Beta 2 Dev3 on Win32 and are\n>trying to determine why. Any info is appreciated.\n>\n>We have a Web Server and a DB server both running Win2KServer with all\n>service packs and critical updates.\n>\n>An ASP page on the Web Server hits the DB... |
[
{
"msg_contents": "Hi all,\n\nI recently migrated my database from schema 'public' to multiple schema.\nI have around 100 tables, and divided them in 14 different schemas, and then adapted my application to use schemas as well.\nI could percept that the query / insert / update times get pretty much faster then ... |
[
{
"msg_contents": "Igor,\n\nI'm not sure if it is proper to state that schemas are themselves speeding things up.\n\nAs an example, we have data that is usually accessed by county; when we put all of the data into one big table and select from it using a code for a county of interest, the process is fairly slow... |
[
{
"msg_contents": "Hi all,\n\nI'm trying to find smarter ways to dig data from my database, and have the following scenario:\n\ntable1\n-- id\n-- name\n.\n.\n.\n.\n.\n.\n\ntable2\n-- id\n-- number\n.\n.\n.\n.\n.\n.\n\nI want to create a view to give me back just what I want:\nThe id, the name and the number.\nI... |
[
{
"msg_contents": "pg to my mind is unique in not trying to avoid OS buffering. Other\ndbmses spend a substantial effort to create a virtual OS (task\nmanagement, I/O drivers, etc.) both in code and support. Choosing mmap\nseems such a limiting an option - it adds OS dependency and limits\nkernel developer opti... |
[
{
"msg_contents": "Hi,\n\nwe are working on a product which was originally developed against an Oracle \ndatabase and which should be changed to also work with postgres. \n\nOverall the changes we had to make are very small and we are very pleased with \nthe good performance of postgres - but we also found quer... |
[
{
"msg_contents": "But he's testing with v8 beta3, so you'd expect the typecast problem not to appear?\n\nAre all tables fully vacuumed? Should the statistics-target be raised for some columns, perhaps? What about the config file?\n\n--Tim\n\n-----Original Message-----\nFrom: pgsql-performance-owner@postgresql.... |
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