Re: Indexing speed

OK, here is my definitive answer to the fastest possible index builds: PSORT_NPROCS=40 #Yeah I know the manual says >10 is noop, try it PSORT_MAXALLOC=10240 #Undocumented but it makes a big difference PSORT_DBTEMP=/a:/b:/c #Set to AT LEAST 3 FILESYSTEMS w/about same free PDQPRIORITY=100 Make sure that the FS in PSORT_DBTEMP with the smallest free space is at least 2/n (n=#FS in the list) of the size of the index. Because of the way sorting and merging are done during the index build you need at least three filesystems to avoid disk contention during merge operations. Thomas J. Girsch wrote: > > A couple of suggestions. For one, try playing with different values for > PSORT_NPROCS. A value of 2 or 3 usually works pretty well for us. > > Another, create the indexes in dbspaces other than the one containing the > table, preferably on a separate physical disk. That should help eliminate > some disk contention. > > And, if you don't already have them, create a couple of temporary dbspaces, > again on separate disks if possible. Informix will use temporary spaces for > the sorts necessary to build the indexes, and this is faster than using file > system space or root space. > >We are running Solaris 2.6, Informix online 7.24.UC5. > >We have set the following: > > > >MAX_PDQPRIORITY 100 > >FILLFACTOR 90> > > >We are creating 3 composite indexes on a table with over a million rows and > >it takes appx 1 hour. Are there any suggestions on improving performance ? Art S. Kagel