PSORT_DBTEMP versus DBSPACETEMP

I know I have read postings in c.d.i which say to use DBSPACETEMP over PSORT_DBTEMP. Plus I read this in the manual: <begin snip> Important: It is recommended that you use the DBSPACETEMP parameter or the DBSPACETEMP environment variable for better performance of sort operations ... <end snip> Does this still apply if my PSORT_DBTEMP variable points to a ram disk? Also is there anything to be gained by specifying more than one directory on the ram disk in the PSORT_DBTEMP variable? Such as PSORT_DBTEMP=/usr/local/ramdisk/sort1:/usr/local/ramdisk/sort2:/usr/local/ramdisk/sort3 I can't run a benchmark on it because we don't have a ramdisk in our testing environment.

bozon wrote: > I know I have read postings in c.d.i which say to use DBSPACETEMP over > PSORT_DBTEMP. Plus I read this in the manual: > > <begin snip> > Important: It is recommended that you use the DBSPACETEMP parameter or > the DBSPACETEMP environment variable for better performance of sort > operations ... > <end snip> Hmm, I've always gotten better performance from PSORT_DBTEMP using 3-2GB partitions either way on similarly configured RAID10 arrays (RAW for the temp dbspaces in DBSPACETEMP, obviously FS COOKED files for PSORT_DBTEMP). > Does this still apply if my PSORT_DBTEMP variable points to a ram disk? > Also is there anything to be gained by specifying more than one > directory on the ram disk in the PSORT_DBTEMP variable? I would definitely lean towards doing PSORT_DBTEMP on the ram disk over temp dbspaces on real disk. However, if you've got one of those persistent RAM drives with a hard drive write-back backup to use for temp dbspaceds it might be a toss up. > Such as > > PSORT_DBTEMP=/usr/local/ramdisk/sort1:/usr/local/ramdisk/sort2:/usr/local/ramdisk/sort3 > > I can't run a benchmark on it because we don't have a ramdisk in our > testing environment. But, you can run a benchmark test offpeak on the production machines. PSORT_DBTEMP and DBSPACETEMP set in the user's environment take precedence over the server's ONCONFIG default and environment settings. Art S. Kagel