Bruce is right... the quote as outlined in the e-mail below is incorrect.
The
exact quote from the Advanced Administration and Troubleshooting "202"
Student
Guide Dated April 2000 (Page 8 of the performance tuning section) is:
"There is an approximate 10% decrease in write performance when the filer attempts to write to a RAID group spanning two adapters. This is due to
inherent
limitations in the PCI bus."
Also, since writes are grouped anyway and responded to immediately, it is not like your write from the client takes 10% longer. Only if the filer is so write-loaded that it's contantly writing, such that future CPs are waiting for the previous CP to complete (the CP taking 10% longer), would the 10% become a noticeable factor in performance. At least that is my understanding - there is probably a slight impact before then just from bus contention issues but I don't think it would be meaningful in most environments.
Bruce