Re: problem with large maintenance_work_mem settings and - Mailing list pgsql-hackers

Stefan Kaltenbrunner <stefan@kaltenbrunner.cc> writes:
> LOG:  begin index sort: unique = f, workMem = 8024000, randomAccess = f
> LOG:  switching to external sort with 28658 tapes: CPU 4.18s/13.96u sec 
> elapsed 32.43 sec
> LOG:  finished writing run 1 to tape 0: CPU 173.56s/3425.85u sec elapsed 
> 3814.82 sec
> LOG:  performsort starting: CPU 344.17s/7013.20u sec elapsed 7715.45 sec
> LOG:  finished writing final run 2 to tape 1: CPU 347.19s/7121.78u sec 
> elapsed 7827.25 sec
> LOG:  performsort done (except 2-way final merge): CPU 348.25s/7132.99u 
> sec elapsed 7846.47 sec

> after that the postmaster is now consuming 99% CPU for about 22 hours(!) 

I'll look into it, but I was already wondering if we shouldn't bound the
number of tapes somehow.  It's a bit hard to believe that 28000 tapes is
a sane setting.
        regards, tom lane