Re: New shared memory segments,while performing a backup

Peter Tashkoff wrote: [SNIP] OK we just ran into this and I made Regency Support dig out the answers for me. DBSPACETEMP is used for the temp tables holding the preimages for dbspaces during the Archive. Versions before 7.3 do not free these temp tables when the associated dbspace is completely archived but only when the Archive completes so you need space for ALL pages modified during the archive for active systems and large databases this can be many GBs. Also the temp tables ARE DISTRIBUTED ACROSS ALL dbspaces listed in DBSPACETEMP but each temp table lives in only one tempspace and the temp tables are assigned to tempspaces on a round robin basis with no consideration to the amount of free space left so that one tempspace can fill, causing the error Fernando reported getting, even when the other temp spaces are nearly empty. Ver 7.3 will fix this as the temp tables will be fragmented across all tempspaces and they will be freed after the dbspace has been archived (I suggested that the scheme could be implemented with less tempspace needed by changing the granularity of the temptables to the chunk level rather than the dbspace level, so far no comment beyond "Hmmmm"). So, while we want multiple tempspaces in DBSPACETEMP to speed sorts, assuming you do not use PSORT_DBTEMP, and segregate temp tables during queries, you want only a few large tempspaces for the Archives so that you are less likely to fill one of them aborting the Archive. Catch-22! I now keep 4-2GB tempspaces (up from 1GB) if I start having trouble I'll have to go to 2-4GB tempspaces instead. Art S. Kagel