Subject: kern/31944: tmpfs keeps too much memory
To: None <kern-bug-people@netbsd.org, gnats-admin@netbsd.org,>
From: None <yamt@mwd.biglobe.ne.jp>
List: netbsd-bugs
Date: 10/29/2005 05:47:00 
>Number:         31944
>Category:       kern
>Synopsis:       tmpfs keeps too much memory
>Confidential:   no
>Severity:       serious
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Oct 29 05:47:00 +0000 2005
>Originator:     YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
>Release:        NetBSD 3.99.10
>Organization:

>Environment:
	
	
System: NetBSD kaeru 3.99.10 NetBSD 3.99.10 (build.kaeru.xen.nodebug) #11: Fri Oct 28 12:14:04 JST 2005 takashi@kaeru:/usr/home/takashi/work/kernel/build.kaeru.xen.nodebug i386
Architecture: i386
Machine: i386
>Description:
	1. tmpfs doesn't free tmpfs_nodes until unmount.

	2. tmpfs ends up to use malloc heavily.  (mainly via uvm_aobj)
	   malloc doesn't return small allocations back to vm.

	3. tmpfs uses too much wired memory.
	   tmpfs_node, uvm_aobj, directory entries, etc.
>How-To-Repeat:
	code inspection.
>Fix:
	1. free them.

	2. don't use malloc.  or modify malloc.

	3. make them pageable.

>Unformatted: