From owner-freebsd-fs Tue Mar 13 12:28:11 2001 Delivered-To: freebsd-fs@freebsd.org Received: from mail.wolves.k12.mo.us (mail.wolves.k12.mo.us [207.160.214.1]) by hub.freebsd.org (Postfix) with ESMTP id B688937B719; Tue, 13 Mar 2001 12:28:06 -0800 (PST) (envelope-from cdillon@wolves.k12.mo.us) Received: from mail.wolves.k12.mo.us (cdillon@mail.wolves.k12.mo.us [207.160.214.1]) by mail.wolves.k12.mo.us (8.9.3/8.9.3) with ESMTP id OAA54718; Tue, 13 Mar 2001 14:28:03 -0600 (CST) (envelope-from cdillon@wolves.k12.mo.us) Date: Tue, 13 Mar 2001 14:28:03 -0600 (CST) From: Chris Dillon To: Poul-Henning Kamp Cc: , Subject: Re: Disk I/O problem in 4.3-BETA In-Reply-To: <8821.984501490@critter> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org CCs trimmed... On Tue, 13 Mar 2001, Poul-Henning Kamp wrote: > > >If NT and FreeBSD both support hinting of metadata writes, it's only a > >matter of time before the hardware support appears. > > I have been looking for a long time for a PCI NVRAM card at a > reasonable cost, anyone know of any with a reasonable price ? How "non-volatile" do you want it to be? I realize truly non-volatile means "forever" (i.e. Flash EEPROM, MRAM, or similar). However, a few minutes/hours (battery-backed volatile RAM) might be enough? The relatively cheap Mylex AcceleRAID 170 we just recently purchased has a "super-cap" (a very high-capacity capacitor, but not exactly a battery) on it, which could theoretically supply power to the on-board cache for at least a few minutes. The documentation and spec sheets for the board mention absolutely nothing about it, but its there. The low-profile version of the board doesn't appear to have the "super-cap", though. I've also got an AMI MegaRAID Enterprise 1200 at home with the small Ni-Cad battery backup module, and it should be able to keep the memory alive for at least a few hours. I think all of AMI's Enterprise level controllers offer that option. -- Chris Dillon - cdillon@wolves.k12.mo.us - cdillon@inter-linc.net FreeBSD: The fastest and most stable server OS on the planet. For IA32 and Alpha architectures. IA64, PPC, and ARM under development. http://www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message