Increasing working memory in psql does not improve query performance












0















I am very new to database administration and could use any advice from more expert users of PostgreSQL



My database is an AWS RDS db.m4.large whose specification are here



My queries against one of the larger tables in the database (330 million rows) are running extremely slow and/or timing out, even when I am have a query such as



SELECT(DISTINCT value) FROM mytable; 


where there are only 4 or 5 unique values in the value column. It is not indexed.



pg_size_pretty(pg_total_relation_size(relid)) shows the size of the table to be 118 GB



Even when setting work_mem to 240 MB, which should allows psql to do larger in-memory sorts, the query is equally as slow



EXPLAIN ANALYZE SELECT(DISTINCT value) FROM mytable;
also times out



What does one do to optimize memory usage for querying on a sufficiently large database? Which pg settings would I need to monitor and/or configure differently ?



Any help would be appreciated.









share



























    0















    I am very new to database administration and could use any advice from more expert users of PostgreSQL



    My database is an AWS RDS db.m4.large whose specification are here



    My queries against one of the larger tables in the database (330 million rows) are running extremely slow and/or timing out, even when I am have a query such as



    SELECT(DISTINCT value) FROM mytable; 


    where there are only 4 or 5 unique values in the value column. It is not indexed.



    pg_size_pretty(pg_total_relation_size(relid)) shows the size of the table to be 118 GB



    Even when setting work_mem to 240 MB, which should allows psql to do larger in-memory sorts, the query is equally as slow



    EXPLAIN ANALYZE SELECT(DISTINCT value) FROM mytable;
    also times out



    What does one do to optimize memory usage for querying on a sufficiently large database? Which pg settings would I need to monitor and/or configure differently ?



    Any help would be appreciated.









    share

























      0












      0








      0








      I am very new to database administration and could use any advice from more expert users of PostgreSQL



      My database is an AWS RDS db.m4.large whose specification are here



      My queries against one of the larger tables in the database (330 million rows) are running extremely slow and/or timing out, even when I am have a query such as



      SELECT(DISTINCT value) FROM mytable; 


      where there are only 4 or 5 unique values in the value column. It is not indexed.



      pg_size_pretty(pg_total_relation_size(relid)) shows the size of the table to be 118 GB



      Even when setting work_mem to 240 MB, which should allows psql to do larger in-memory sorts, the query is equally as slow



      EXPLAIN ANALYZE SELECT(DISTINCT value) FROM mytable;
      also times out



      What does one do to optimize memory usage for querying on a sufficiently large database? Which pg settings would I need to monitor and/or configure differently ?



      Any help would be appreciated.









      share














      I am very new to database administration and could use any advice from more expert users of PostgreSQL



      My database is an AWS RDS db.m4.large whose specification are here



      My queries against one of the larger tables in the database (330 million rows) are running extremely slow and/or timing out, even when I am have a query such as



      SELECT(DISTINCT value) FROM mytable; 


      where there are only 4 or 5 unique values in the value column. It is not indexed.



      pg_size_pretty(pg_total_relation_size(relid)) shows the size of the table to be 118 GB



      Even when setting work_mem to 240 MB, which should allows psql to do larger in-memory sorts, the query is equally as slow



      EXPLAIN ANALYZE SELECT(DISTINCT value) FROM mytable;
      also times out



      What does one do to optimize memory usage for querying on a sufficiently large database? Which pg settings would I need to monitor and/or configure differently ?



      Any help would be appreciated.







      postgresql psql





      share












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      the_darksidethe_darkside

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