Hi Claudio, how can I do that ? Can you explain me what is this option ? 2017-08-24 2:15 GMT+03:00 Claudio Freire <klaussfre...@gmail.com>:
> On Mon, Aug 21, 2017 at 5:00 AM, Mariel Cherkassky > <mariel.cherkas...@gmail.com> wrote: > > To summarize, I still have performance problems. My current situation : > > > > I'm trying to copy the data of many tables in the oracle database into my > > postgresql tables. I'm doing so by running insert into > local_postgresql_temp > > select * from remote_oracle_table. The performance of this operation are > > very slow and I tried to check the reason for that and mybe choose a > > different alternative. > > > > 1)First method - Insert into local_postgresql_table select * from > > remote_oracle_table this generated total disk write of 7 M/s and actual > disk > > write of 4 M/s(iotop). For 32G table it took me 2 hours and 30 minutes. > > > > 2)second method - copy (select * from oracle_remote_table) to /tmp/dump > > generates total disk write of 4 M/s and actuval disk write of 100 K/s. > The > > copy utility suppose to be very fast but it seems very slow. > > Have you tried increasing the prefetch option in the remote table? > > If you left it in its default, latency could be hurting your ability > to saturate the network. >
