Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-07-14 Thread Robert Haas
On Wed, Feb 10, 2010 at 12:19 AM, Tom Lane wrote: > Andrew Dunstan writes: >> Tom Lane wrote: >>> The code is only trying to substitute for something you can't have >>> in parallel restore, ie --single-transaction. > >> Exactly. IIRC that's why --single-transaction was introduced in the >> first

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-07-06 Thread Marc Cousin
2010/2/10 Takahiro Itagaki > > Tom Lane wrote: > > > Takahiro Itagaki writes: > > > We have an optimization to bulkload date in pg_restore, but the code > > > only works in parallel restore (--jobs >= 2). Why don't we do the > > > same optimization in the serial restore (--jobs = 1) ? > > > > T

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-02-09 Thread Takahiro Itagaki
Andrew Dunstan wrote: > Takahiro-san is suggesting there is a case for doing the optimisation in > non-parallel mode. But if we do that, is there still a case for > --single-transaction? I think --single-transaction is useful to restore data into non-empty databases. A normal restore ignores

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-02-09 Thread Tom Lane
Andrew Dunstan writes: > Tom Lane wrote: >> The code is only trying to substitute for something you can't have >> in parallel restore, ie --single-transaction. > Exactly. IIRC that's why --single-transaction was introduced in the > first place. To me, --single-transaction is mostly there for pe

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-02-09 Thread Andrew Dunstan
Tom Lane wrote: Takahiro Itagaki writes: We have an optimization to bulkload date in pg_restore, but the code only works in parallel restore (--jobs >= 2). Why don't we do the same optimization in the serial restore (--jobs = 1) ? The code is only trying to substitute for something

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-02-09 Thread Takahiro Itagaki
Tom Lane wrote: > Takahiro Itagaki writes: > > We have an optimization to bulkload date in pg_restore, but the code > > only works in parallel restore (--jobs >= 2). Why don't we do the > > same optimization in the serial restore (--jobs = 1) ? > > The code is only trying to substitute for som

Re: [HACKERS] TRUNCATE+COPY optimization and --jobs=1 in pg_restore

2010-02-09 Thread Tom Lane
Takahiro Itagaki writes: > We have an optimization to bulkload date in pg_restore, but the code > only works in parallel restore (--jobs >= 2). Why don't we do the > same optimization in the serial restore (--jobs = 1) ? The code is only trying to substitute for something you can't have in parall