VxFS, Oracle disk-manager and write-lock

[Database Administrator]

I recently ran across some literature, passed to me by a co-worker,
related to Oracle disk-manager and vxfs. The literature was written
towards SUN / VxFS, but mentioned that one of the largest ODM
advantages was its ability to overcome VxFS single-thread write.

I'm curious if anyone knows if HP/vxfs shows contention under high I/O
due to a single-writer lock. The literature claims that single-writer
lock (on a highly-active filesystem) should create noticeable
contention / performance degradation; however, I haven't personally
seen it and am wondering how it manifests itself.

Regards,

Joe Ferraro