> On Oct 10, 2018, at 1:24 PM, Andres Freund <andres@xxxxxxxxxxx> wrote: > > On 2018-10-10 18:50:02 +0200, Laurenz Albe wrote: >> Rob Sargent wrote: >>> Can anyone here tell me whether or not the CopyManager facility in JDBC >>> via org.postgresql:postgresql:42.1.4 is internally multithreaded? >>> Running on CentOS 7 (all participants), java8, postgres 10.5 >> >> It isn't, and there would not be much reason for it to be, as COPY >> in PostgreSQL cannot be parallelized. > > s/cannot/is not/. > > You obviously can just copy the data into postgres over multiple > connections if you need to speed COPY up. But that requires splitting up > the data on the clientside. > > Greetings, > > Andres Freund Interesting note, deeply pocketed. The COPY portion is /not/ my problem - that’s plenty fast enough and memory efficient enough straight from the box. I had over looked that I was requesting 33M records, in a map with a longish CSV string as key...then playing sort games with keys and ... well that’s as stupid as I got.
