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: