Environment
Novell NetWare 6.5 Support Pack 6
Novell NetWare 6.5 Support Pack 7
Adaptec Adpahci.ham v1.21
Situation
Slow storage performance on NetWare 6.5 servers utilizing adpahci.ham version 1.21 driver dated May 6, 2006. Performance is well in the single digit Megabyte/sec range.
Multiple CPUs seem to be the cause. The performance issue only exists on servers with more than one physical CPU. Dual Core CPUs are also affected.
Resolution
Make sure that only one CPU is active at the load time of the driver. This can be done by setting "set auto restart processors" to "off" and then adding "start processor 1" (for the second CPU, if more than two CPUs are used add more "start processor" lines) somewhere early in the autoexec.ncf file