Hi,
We have a number of SAP DB instances on HPUX (oracle 11g2) using JFS (cooked filesystems rather than ASM). Filesystems are mounted with CIO (concurrent IO), and JFS does not support sync IO (so its sync io with cio support at the OS/FS).
REDO is written to only a single group member (ie not mirrored logs)
Redo write time are high, even thought back end SAN is caching all wites (writes are sync written to the DR storage from the local array as well).
What I an looking for is recommendations on how to configure the REDO devices (ie array based stripping, host based stripping of multiple storage devices).
As REDO is a single treaded (ie LGWR) and does siquentiual IO I am not sure what benefit can be obtained by stipping of the LUNs underlying the REDO filesystems (using /oracle/<SID>/origlogA and origlogB).
Advise gratefully accepted.
Regards
Glenn