Обсуждение: does work_mem is used on temp tables?
Hi,
Does the work mem is used when I do sorts or hash operations on temp tables ? Or the temp_buffer that is allocated at the beginning of the session is used for it ?
At one of our apps, the app create a temp table and run on it some operations (joins,sum,count,avg ) and so on.. I saw in the postgresql.conf that fs temp files are generated so I guested that the memory buffer that was allocated for that session was too small. The question is should I increase the work_mem or the temp_buffers ?
Thanks , Mariel.
>>>>> "Mariel" == Mariel Cherkassky <mariel.cherkassky@gmail.com> writes: Mariel> Hi, Mariel> Does the work mem is used when I do sorts or hash operations on Mariel> temp tables ? Or the temp_buffer that is allocated at the Mariel> beginning of the session is used for it ? work_mem is used for sorts and hashes regardless of what type the underlying table (if any) is. temp_buffers is used to buffer the actual _content_ of temp tables. -- Andrew (irc:RhodiumToad)
>>>>> "Mariel" == Mariel Cherkassky <mariel.cherkassky@gmail.com> writes: Mariel> Hi, Mariel> Does the work mem is used when I do sorts or hash operations on Mariel> temp tables ? Or the temp_buffer that is allocated at the Mariel> beginning of the session is used for it ? work_mem is used for sorts and hashes regardless of what type the underlying table (if any) is. temp_buffers is used to buffer the actual _content_ of temp tables. -- Andrew (irc:RhodiumToad)
great, thanks !
בתאריך יום ה׳, 11 באוק׳ 2018 ב-10:42 מאת Andrew Gierth <andrew@tao11.riddles.org.uk>:
>>>>> "Mariel" == Mariel Cherkassky <mariel.cherkassky@gmail.com> writes:
Mariel> Hi,
Mariel> Does the work mem is used when I do sorts or hash operations on
Mariel> temp tables ? Or the temp_buffer that is allocated at the
Mariel> beginning of the session is used for it ?
work_mem is used for sorts and hashes regardless of what type the
underlying table (if any) is.
temp_buffers is used to buffer the actual _content_ of temp tables.
--
Andrew (irc:RhodiumToad)
great, thanks !
בתאריך יום ה׳, 11 באוק׳ 2018 ב-10:42 מאת Andrew Gierth <andrew@tao11.riddles.org.uk>:
>>>>> "Mariel" == Mariel Cherkassky <mariel.cherkassky@gmail.com> writes:
Mariel> Hi,
Mariel> Does the work mem is used when I do sorts or hash operations on
Mariel> temp tables ? Or the temp_buffer that is allocated at the
Mariel> beginning of the session is used for it ?
work_mem is used for sorts and hashes regardless of what type the
underlying table (if any) is.
temp_buffers is used to buffer the actual _content_ of temp tables.
--
Andrew (irc:RhodiumToad)