kern/71968: USB disk triggers swap activity

[Walter C. Pelissero]

>Number:         71968
>Category:       kern
>Synopsis:       USB disk triggers swap activity
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Sep 21 12:00:42 GMT 2004
>Closed-Date:
>Last-Modified:
>Originator:     Walter C. Pelissero
>Release:        FreeBSD 5.2.1-RELEASE-p9 i386
>Organization:
>Environment:
System: FreeBSD hyde.home.loc 5.2.1-RELEASE-p9 FreeBSD 5.2.1-RELEASE-p9 #1: Tue Aug 24 10:06:14 CEST 2004 root at hyde.home.loc:/usr/src/sys/i386/compile/PCG-XG9 i386


	Sony Vaio PCG-XG9, LaCie 160G USB2 disk with UFS2 filesystem
	mounted automatically by amd.
>Description:
	When I do a substantial activity on a 160G USB2 disk the
	system starts an heavy ATA disk activity that looks like
	swapping because, even though there is still 50MB RAM
	available, the swap usage jumps up to 14% and then slowly
	reaches 17%.  Soon, one by one, the programs become
	irresponsive and the system grinds to a halt (but the ATA
	activity).  If I don't try it immediately, ssh from another
	node yields a connection timeout.  Needless to say the USB
	keyboard and mouse die immediately, while I can still use the
	trackpad on the laptop.
>How-To-Repeat:
	dd if=/dev/zero of=/path/to/the/usb/filesystem
>Fix:




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