On Tue, Nov 8, 2016 at 1:53 PM, Hector Yuen <hec...@infer.com> wrote:
> Hello, > > I am confused on which are the parameters for different queries. I am > trying to run VACUUM on a big table, and it is easier for me to set the > work memory for the specific session instead of tuning it in > postgresql.conf. > > I noticed that if I do: > > set work_mem='1GB'; > > it doesn't help VACUUM, I have to do: > > set maintenance_work_mem='1GB'; > > to accelerate the operation. I could notice that by running VACUUM VERBOSE > and see that the table was scanned less times an the operation finished a > lot faster. > > My question is, for which operations does work_mem matter and for which > ones does maintenance_work_mem do? I am specially interested in operations > like ANALYZE and VACUUM, I believe ANALYZE depends on work_mem and VACUUM > on maintenance_work_mem. > > Can you confirm my understanding? > > Thanks > > -- > -h > *>I believe ANALYZE depends on work_mem and VACUUM on maintenance_work_mem.* *No, ANALYZE is part of VACUUM. They both use maintenance_work_mem.* *https://www.postgresql.org/docs/9.4/static/runtime-config-resource.html#RUNTIME-CONFIG-RESOURCE-MEMORY <https://www.postgresql.org/docs/9.4/static/runtime-config-resource.html#RUNTIME-CONFIG-RESOURCE-MEMORY>* -- *Melvin Davidson* I reserve the right to fantasize. Whether or not you wish to share my fantasy is entirely up to you.
