Re: [GENERAL] Problems with memory
Richard Huxton wrote: Pau Marc Munoz Torres wrote: Hi To your initial question all configurable options can be found and adjusted in the postgresql.conf which can be found in the top of your data dir. You can find more detail on what the options are for at http://www.postgresql.org/docs/8.3/interactive/runtime-config.html Although I doubt it will fix your problem you will most likely want to tune them to get the best performance from your db once it goes live. maybe i should give you some more explanations of my problem. The reason for which i think that postgresql run out of memory is that: I have a relation with 6 fields, 29 indexes and 32000 registers, the registers So how much ram does your machine have? have you looked at how much postgres is using while it is running the queries? What CPU's and disks/raid controller? when i do a query as: select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')<-2; it works and return 128030 registers if i do select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')>-2; 3071970 registers, it don't work ERROR: relation "pssms" does not exist CONTEXT: SQL statement "select score from PSSMS where AA= $1 and POS=1 and MOLEC= $2 " PL/pgSQL function "idr" line 11 at SQL statement Start with the idr function - this is where the error comes from. The error doesn't mention out of memory. if i ask for explanation for both queries works: explain will show what the planner expects to do. explain analyse will actually run through the query and give exact row counts returned etc. and will hit the error that you get when running the query. If for that reason that i think that my machine runs out of memory, by the way, this is not the biggest table that i have others have more than 50300 registers, so if I try to do a cross select between tables it could be worse. You may hear from people on this list that have db's storing many TeraBytes of data. -- Shane Ambler pgSQL (at) Sheeky (dot) Biz Get Sheeky @ http://Sheeky.Biz -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] Problems with memory
Pau Marc Munoz Torres wrote: Hi maybe i should give you some more explanations of my problem. The reason for which i think that postgresql run out of memory is that: I have a relation with 6 fields, 29 indexes and 32000 registers, the registers where made up using a pgsql language to save disk space, and they "work" (see the table schema under those lines) You have 29 indexes on a table with 6 columns? But only 32000 rows? Column | Type | Modifiers +--+--- id | integer | p1 | character(1) | p4 | character(1) | p6 | character(1) | p7 | character(1) | p9 | character(1) | Indexes: "h2iab" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAb'::character varying)) "h2iad" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAd'::character varying)) "h2iak" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAk'::character varying)) "h2ied" btree (idr(p1, p4, p6, p7, p9, 'H-2*IEd'::character varying)) etc. OK, so you have 29 different functional indexes which use your columns and then a fixed parameter. Looks odd to me, but I suppose you might have good reason. Oh - and it's not necessarily saving you any disk space - the index values need to be stored. when i do a query as: select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')<-2; it works and return 128030 registers if i do select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')>-2; 3071970 registers, it don't work ERROR: relation "pssms" does not exist CONTEXT: SQL statement "select score from PSSMS where AA= $1 and POS=1 and MOLEC= $2 " PL/pgSQL function "idr" line 11 at SQL statement Do you have a table/view called pssms in your search-path? Because that's what the error is about. Might it be a case-sensitive issue - do you have a table called PSSMS instead? if i ask for explanation for both queries works: mhc2db=> explain select count(*) from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')<-2; [snip] mhc2db=> explain select count(*) from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')>-2; [snip] and the index used are the correct ones If for that reason that i think that my machine runs out of memory, by the way, this is not the biggest table that i have others have more than 50300 registers, so if I try to do a cross select between tables it could be worse. For what reason? I still don't see any out-of-memory errors. -- Richard Huxton Archonet Ltd -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] Problems with memory
Hi maybe i should give you some more explanations of my problem. The reason for which i think that postgresql run out of memory is that: I have a relation with 6 fields, 29 indexes and 32000 registers, the registers where made up using a pgsql language to save disk space, and they "work" (see the table schema under those lines) Column | Type | Modifiers +--+--- id | integer | p1 | character(1) | p4 | character(1) | p6 | character(1) | p7 | character(1) | p9 | character(1) | Indexes: "h2iab" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAb'::character varying)) "h2iad" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAd'::character varying)) "h2iak" btree (idr(p1, p4, p6, p7, p9, 'H-2*IAk'::character varying)) "h2ied" btree (idr(p1, p4, p6, p7, p9, 'H-2*IEd'::character varying)) "hladqa10501" btree (idr(p1, p4, p6, p7, p9, 'HLA-DQA1*0501'::character varying)) "hladqb10201" btree (idr(p1, p4, p6, p7, p9, 'HLA-DQB1*0201'::character varying)) "hladr" btree (idr(p1, p4, p6, p7, p9, 'HLA-DR'::character varying)) "hladr1" btree (idr(p1, p4, p6, p7, p9, 'HLA-DR1'::character varying)) "hladr13" btree (idr(p1, p4, p6, p7, p9, 'HLA-DR13'::character varying)) "hladr3" btree (idr(p1, p4, p6, p7, p9, 'HLA-DR3'::character varying)) "hladr7" btree (idr(p1, p4, p6, p7, p9, 'HLA-DR7'::character varying)) "hladrb10101" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101'::character varying)) "hladrb10102" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0102'::character varying)) "hladrb10301" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0301'::character varying)) "hladrb10302" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0302'::character varying)) "hladrb10401" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0401'::character varying)) "hladrb10402" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0402'::character varying)) "hladrb10701" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0701'::character varying)) "hladrb10802" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0802'::character varying)) "hladrb10901" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0901'::character varying)) "hladrb11101" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1101'::character varying)) "hladrb11102" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1102'::character varying)) "hladrb11103" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1103'::character varying)) "hladrb11104" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1104'::character varying)) "hladrb11301" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1301'::character varying)) "hladrb11302" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1302'::character varying)) "hladrb11501" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*1501'::character varying)) "hladrb40101" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB4*0101'::character varying)) "hladrb50101" btree (idr(p1, p4, p6, p7, p9, 'HLA-DRB5*0101'::character varying)) when i do a query as: select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')<-2; it works and return 128030 registers if i do select * from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')>-2; 3071970 registers, it don't work ERROR: relation "pssms" does not exist CONTEXT: SQL statement "select score from PSSMS where AA= $1 and POS=1 and MOLEC= $2 " PL/pgSQL function "idr" line 11 at SQL statement if i ask for explanation for both queries works: mhc2db=> explain select count(*) from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')<-2; QUERY PLAN Aggregate (cost=66188.88..66188.89 rows=1 width=0) -> Bitmap Heap Scan on precalc (cost=17615.20..63522.21 rows=107 width=0) Recheck Cond: (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101'::character varying) < -2::double precision) -> Bitmap Index Scan on hladrb10101 (cost=0.00..17348.54 rows=107 width=0) Index Cond: (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101'::character varying) < -2::double precision) (5 rows) mhc2db=> explain select count(*) from precalc where idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101')>-2; QUERY PLAN Aggregate (cost=66188.88..66188.89 rows=1 width=0) -> Bitmap Heap Scan on precalc (cost=17615.20..63522.21 rows=107 width=0) Recheck Cond: (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101'::character varying) > -2::double precision) -> Bitmap Index Scan on hladrb10101 (cost=0.00..17348.54 rows=107 width=0) Index Cond: (idr(p1, p4, p6, p7, p9, 'HLA-DRB1*0101'::character varying) > -2::double precision) (5 rows) and the index used are the correct ones If for that reason that i think that my machine runs out of memo
[GENERAL] Problems with memory
Hi I'm setting up a big database , and when i say big, i mean BIG, the problem with this is that some times, when a do a query the database run out of memory, so I really need to increase the amount of memory reserved to postgress almost 10x, could anyone tell me how can i do that? i mean, what configuration file and variables do i have to modify? Thanks pau -- Pau Marc Muñoz Torres Laboratori de Biologia Computacional Institut de Biotecnologia i Biomedicina Vicent Villar Universitat Autonoma de Barcelona E-08193 Bellaterra (Barcelona) telèfon: 93 5812807 Email : [EMAIL PROTECTED]
Re: [GENERAL] Problems with memory
On Wed, May 7, 2008 at 11:55 AM, Pau Marc Munoz Torres <[EMAIL PROTECTED]> wrote: > Hi > > I'm setting up a big database , and when i say big, i mean BIG, the problem > with this is that some times, when a do a query the database run out of > memory, so I really need to increase the amount of memory reserved to > postgress almost 10x, could anyone tell me how can i do that? i mean, what > configuration file and variables do i have to modify? All available memory of the machine is automatically reserved for the database by the operating system, more or less. At most you can reserve memory for certain particular operations of the database at the expense of others. merlin -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
Re: [GENERAL] Problems with memory
Pau Marc Munoz Torres wrote: Hi I'm setting up a big database , and when i say big, i mean BIG, I have to say, I've seen more accurate stats given. How many Terabytes are we talking about? > the problem with this is that some times, when a do a query the database run out of memory, What precisely do you mean by "run out of memory" - is this work-mem or shared-mem? How do you know this is what's happening? > so I really need to increase the amount of memory reserved to postgress almost 10x, could anyone tell me how can i do that? i mean, what configuration file and variables do i have to modify? What memory are you trying to reserve for PostgreSQL? Is it shared-mem you're talking about? If you let us know where you found the manuals confusing, we can try to improve them. -- Richard Huxton Archonet Ltd -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
[GENERAL] Problems with memory
Hi I'm setting up a big database , and when i say big, i mean BIG, the problem with this is that some times, when a do a query the database run out of memory, so I really need to increase the amount of memory reserved to postgress almost 10x, could anyone tell me how can i do that? i mean, what configuration file and variables do i have to modify? Thanks pau -- Pau Marc Muñoz Torres Laboratori de Biologia Computacional Institut de Biotecnologia i Biomedicina Vicent Villar Universitat Autonoma de Barcelona E-08193 Bellaterra (Barcelona) telèfon: 93 5812807 Email : [EMAIL PROTECTED]
Re: [GENERAL] problems with memory
> * Dean Browett <[EMAIL PROTECTED]> [000218 15:55] wrote: > > Hi, > > > > We are running postgres-6.5.3 on a dual pentium 300 machine, 0.5Gb RAM under > > Linux Redhat 6.0 (kernel 2.2.14). The machine we are using sits on a 100Mb > > network and the nics are 3com3c590's. We are also using a DPT Raid > > controller in a raid5 configuration set up as 1 logical drive. > > > > We are try to insert a large amount of data into the database. What happens > > is that when we first start loading data everything is fine. Over a period > > of time (1.5hrs) there is a marked decrease in performance in terms of both > > memory and cpu usage. At this time cpu usage has crept up to 45-50% and > > memory usage is 100Mb and rising slowly and there is only one connection to > > the database. > > > > All the statistics are gleaned from using 'top'. > > > > > > Consequently, the database gets slower and slower until it loads at the rate > > of <3KBps at which point it becomes more exciting to watch paint dry 8-)). > > > > Postgres is the only program running (except for normal system programs) > > that uses a significant amount of memory. > > > > Is Postgres known to leak memory? What causes the high cpu usage? > > > > Any ideas would be greatly appreciated. > > You really haven't given very much information on the rules and constraints > in your tables, one problem that I had was that a constraint on a table > of mine caused extreme slowdown because each row inserted needed to be > validated through a constraint, as the table grew the amount of data that > needed to be scanned for each insert grew exponentially. > > hope this helps, > -Alfred The same is true of any type of index. Make sure you don't have indices defined unitl after the insert. Also, do a COPY instead of INSERT if possible. --Gene
Re: [GENERAL] problems with memory
* Dean Browett <[EMAIL PROTECTED]> [000218 15:55] wrote: > Hi, > > We are running postgres-6.5.3 on a dual pentium 300 machine, 0.5Gb RAM under > Linux Redhat 6.0 (kernel 2.2.14). The machine we are using sits on a 100Mb > network and the nics are 3com3c590's. We are also using a DPT Raid > controller in a raid5 configuration set up as 1 logical drive. > > We are try to insert a large amount of data into the database. What happens > is that when we first start loading data everything is fine. Over a period > of time (1.5hrs) there is a marked decrease in performance in terms of both > memory and cpu usage. At this time cpu usage has crept up to 45-50% and > memory usage is 100Mb and rising slowly and there is only one connection to > the database. > > All the statistics are gleaned from using 'top'. > > > Consequently, the database gets slower and slower until it loads at the rate > of <3KBps at which point it becomes more exciting to watch paint dry 8-)). > > Postgres is the only program running (except for normal system programs) > that uses a significant amount of memory. > > Is Postgres known to leak memory? What causes the high cpu usage? > > Any ideas would be greatly appreciated. You really haven't given very much information on the rules and constraints in your tables, one problem that I had was that a constraint on a table of mine caused extreme slowdown because each row inserted needed to be validated through a constraint, as the table grew the amount of data that needed to be scanned for each insert grew exponentially. hope this helps, -Alfred
[GENERAL] problems with memory
Hi, We are running postgres-6.5.3 on a dual pentium 300 machine, 0.5Gb RAM under Linux Redhat 6.0 (kernel 2.2.14). The machine we are using sits on a 100Mb network and the nics are 3com3c590's. We are also using a DPT Raid controller in a raid5 configuration set up as 1 logical drive. We are try to insert a large amount of data into the database. What happens is that when we first start loading data everything is fine. Over a period of time (1.5hrs) there is a marked decrease in performance in terms of both memory and cpu usage. At this time cpu usage has crept up to 45-50% and memory usage is 100Mb and rising slowly and there is only one connection to the database. All the statistics are gleaned from using 'top'. Consequently, the database gets slower and slower until it loads at the rate of <3KBps at which point it becomes more exciting to watch paint dry 8-)). Postgres is the only program running (except for normal system programs) that uses a significant amount of memory. Is Postgres known to leak memory? What causes the high cpu usage? Any ideas would be greatly appreciated. Dean