All my SAP systems are on HPUX 10.20. We are going to implement these on to HPUX11, 64bit kernel. Can you suggest or share about your experiences on this move? Thank you.
In my experience this move has been excellent (especially for HPUX)! Under HPUX, and 32 bit SAP/Oracle one could only allocate 1.75 gig of shared memory. This means that memory 'pools' like the ABAP buffer (ABAP/buffersize), extended memory (em/initial_size_KB), Oracle data buffer (db_block_buffers), Oracle shared pool (shared_pool_size) have to be watched very closely so as not to exceed the limit (as a total).
Once you move to 64-bit, this limit goes away. The only issue at that point are the appropriate Unix level kernel settings (shmmax, etc.), and the amount of real memory/swap space on the hardware. By moving to 64-bit, I have been able to consolidate some hardware to reduce overall costs.
This was first published in December 2001