Hi Andres, On Mon, May 6, 2019 at 8:09 PM Andres Freund <andres@xxxxxxxxxxx> wrote: > > Hi, > > On 2019-05-06 16:54:08 +0530, Siddharth Karandikar wrote: > > I am trying to restore database dump created on PostgreSQL 9.5.16 to > > PostgreSQL 10.7 and it is taking a lot of time to restore. Restoring > > the same dump to 9.5 doesn't take that much. So I am wondering what > > could be reason behind this slowness. > > Is there any chance the configuration is different between 9.5 and 10? I double checked, but there is no difference in configurations of 9.5 and 10. 9.5 restore works fine with maintenance_work_mem set to 16MB. But I will rerun restore on 10 with higher maintenance_work_mem. > If there e.g. is an index on the table, the maintanance_work_mem setting > would make a large differerence when rebuilding. Note that the > medium-tablecase is noticably faster in 10 and that there's been some > speedup work around that in 10. > > > > > Postgres configuration that I have on this setup: > > shared_buffers = 128MB > > > > work_mem = 1MB > > maintenance_work_mem = 16MB > > maintenance_work_mem = 16Mb is a very low value - it's e.g. used for > index builds, to sort the data. > > Greetings, > > Andres Freund