kern/156647: Intel ICH7 SATA300 Driver Performance Regression in 8.2-STABLE

[Conall O'Brien]

>Number:         156647
>Category:       kern
>Synopsis:       Intel ICH7 SATA300 Driver Performance Regression in 8.2-STABLE
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Apr 25 17:20:09 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Conall O'Brien
>Release:        FreeBSD 8.2-PRERELEASE amd64
>Organization:
>Environment:

Motherboard: Intel D510

Unaffected System: FreeBSD galvatron.taku.ie 8.2-PRERELEASE FreeBSD 8.2-PRERELEASE #0: Wed Dec 29 04:00:27 UTC 2010 root at galvatron.taku.ie:/usr/src/obj/usr/src/sys/GALVATRON amd64

Affected System: FreeBSD galvatron.taku.ie 8.2-STABLE FreeBSD 8.2-STABLE #1: Sat Mar 19 13:18:46 UTC 2011 root at galvatron.taku.ie:/usr/src/obj/usr/src/sys/GALVATRON amd64

>Description:

	SATA disks connected via the onboard Intel ICH7 SATA300 controller 
	become troublesome to use. I/O  queues fill up and kernel reports 
   frequent DMA issues for each SATA disk on the controller on the console


>How-To-Repeat:
	Run the 8.2-STABLE kernel on a system with multiple disks and the 
	ICH7 SATA300.
>Fix:

	Revert back to a RLEENG_8 kernel built before 8.2-RELEASE was cut.

>Release-Note:
>Audit-Trail:
>Unformatted: