[Q] Cry for help: how to make exp faster?

Hello,
we are running an Oracle 7.3.4.4.0 on raw device on RS/6000 AIX V4.3.2.-02 (node has 4 CPU at 332 MHz), disk subsystem is 7133-020 SSA technology (disks are 9.1 GB).
I have written a procedure that makes backup of Oracle in "raw mode", means saving the data files / raw logical volumes, which works all right and, of course, runs in always the same time unless data files would be added.

The application/database is not completely in production yet as we are converting data from "old" mainframe system to new Unix system in cycles. We have still some months to go... In the meantime, logical export seems to be a good way (seemed) to save data for the development team. In the first place I saved data via pipe immediately onto tape drive (IBM 3590) which was all right for the first converted cycle as it took up about 45 min. Now, with four cycles and, to improve performance, exporting to a file on file system (jfs) for 2,3 GB of resulting export file it takes up about 6 hours (tape took about 7,5 hours).
Monday I used direct=Y, compress=Y and index=N options (6 hours). Yesterday I used direct=N, compress=Y and index=Y options (8 hours). As I see from resulting export file index=N or Y seems not to make really difference as speaking of export file length, but as I saw makes a difference in time.
Buffer for export is set to about 75 MB, I could afford some more, I guess. Maybe a renice could help some?

Please be so kind to share your experience about making exports or database backup in general. Please point out where to find appropriate documentation about export or database backup tuning. Maybe there is a better way to save the data, besides export or physical backup? Does EBU work faster?

Thank you for your valuable time and hints. Have a nice day.
Regards, Igor Received on Thu Aug 12 1999 - 01:29:39 CDT