From owner-freebsd-stable Wed Nov 14 7:30:41 2001 Delivered-To: freebsd-stable@freebsd.org Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [134.226.81.11]) by hub.freebsd.org (Postfix) with SMTP id 4559D37B418; Wed, 14 Nov 2001 07:30:33 -0800 (PST) Received: from lanczos.maths.tcd.ie by salmon.maths.tcd.ie with SMTP id ; 14 Nov 2001 15:30:32 +0000 (GMT) Date: Wed, 14 Nov 2001 15:30:31 +0000 From: David Malone To: Eugene Grosbein Cc: stable@freebsd.org, hackers@freebsd.org Subject: Re: kern.vm.kmem.size Message-ID: <20011114153031.A16886@lanczos.maths.tcd.ie> References: <20011111230817.A2325@grosbein.pp.ru> <20011113151329.A44837@walton.maths.tcd.ie> <20011113224730.A864@grosbein.pp.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20011113224730.A864@grosbein.pp.ru>; from eugen@grosbein.pp.ru on Tue, Nov 13, 2001 at 10:47:30PM +0700 Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Tue, Nov 13, 2001 at 10:47:30PM +0700, Eugene Grosbein wrote: > > you have enough physical memory. (By default there is about 1GB of > > kernel address space, so you are unlikely to be running into this > > limit - I don't think changing kern.vm.kmem.size will help you). > > Are you shure? From LINT: You're right - it is much smaller (I was thinking of something else). However it is bigger than 12MB on most systems - I think it will turn out to be 1/3 physical memory or 200MB, whichever is less. > It seems DIRHASH is limited with free space in the kernel malloc area. > It even cannot utilize default 2M of vfs.ufs.dirhash_maxmem when I do not > increase kern.vm.kmem.size. > > So, how can I estimate needed value of kern.vm.kmem.size? How much ram do you have in the machine? On a 4.4-RC1 machine with 128MB of ram we don't have any problems getting dirhash to use almost all of it's 2MB: vfs.ufs.dirhash_maxmem: 2097152 vfs.ufs.dirhash_mem: 2085797 This is with the devault value for kern.vm.kmem.size. Maybe you could print the value your system is getting with: echo print vm_kmem_size | gdb -k /kernel /dev/mem David. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message