onbar

Running IDS 9.40.FC5 onbar with ISM, Solaris 9 I'm planning to upgrade to 10 or 11 asap and want to use archecker for table-level restore. Currently, we have a hodge-podge of unload files and a level 0 onbar taken weekly to put the database back in case of a complete loss. I want to start using the onbar for table-level restore and full recovery and eliminate unloading data to files altoghether. I haven't thought through it all yet but think that adding some incremental onbars between level 0s would cover the full backup. If I read correctly, table-level restore can only be done from a level 0. Problem is, the level 0 onbar takes 8 hours to run with little or no traffic on the database. Any user traffic at all seems to slow it down significantly pushing the completion time out. Suggesting that the database be down for 8 hours or more every night or so won't go over well. I'm running 4 devices to files and putting the files on tape after completion. Is 4 the magic number for ISM - can't get it to run any more it gives an error. It looks like a device equates to a thread - is that so? The entire database is roughly 2 TB of actual data. I didn't think that was too terrible - 2TB in 8 hrs. Anyone have anything to compare that time to? Any suggestions on how I can speed this up? thanks in advance