Re: lock contention on parallel COPY ?

On Fri, 2008-09-26 at 20:07 +0200, Stefan Kaltenbrunner wrote:
> Tom Lane wrote:
> > Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
> >> Stefan Kaltenbrunner <stefan(at)kaltenbrunner(dot)cc> writes:
> >>> samples % symbol name
> >>> 55526 16.5614 LWLockAcquire
> >>> 29721 8.8647 DoCopy
> >>> 26581 7.9281 CopyReadLine
> >>> 25105 7.4879 LWLockRelease
> >>> 15743 4.6956 PinBuffer
> >>> 14725 4.3919 heap_formtuple
> >
> >> Probably loading a table with a generated PK or loading data in
> >> ascending sequence, so its contending heavily for the rightmost edge of
> >> the index.
> >
> > No, given that DoCopy and CopyReadLine are right up there, I think we're
> > still looking at the COPY phase, not index building.
> >
> > The profile will probably change completely once index building
> > starts...
>
> yeah this profile is only showing the COPY phase ...

Try using this Postgres core patch. It's a updated version of my
fast_copy.v4.patch from Patches: Bulk Insert tuning 20 Mar 2008

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Simon Riggs www.2ndQuadrant.com
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