Return to BSD News archive
Newsgroups: comp.unix.bsd.freebsd.misc Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!nntp.coast.net!chi-news.cic.net!newsfeed.internetmci.com!in1.uu.net!brighton.openmarket.com!decwrl!pagesat.net!quack!quack.kfu.com!nsayer From: nsayer@quack.kfu.com (Nick Sayer) Subject: Prestoserve for FreeBSD? Message-ID: <nbg0Z9M@quack.kfu.com> Sender: news@quack.kfu.com (0000-News(0000)) Organization: The Duck Pond public unix, +1 408 249 9630, log in as guest. Date: Thu, 14 Dec 1995 21:39:25 UTC Lines: 23 For those of you unfamiliar with the concept, PrestoServe is an idea Legato came up with and Sun ended up selling for sparc servers. In short, it is a board with 1M of NVRAM (battery backed static). The RAM is used by a little driver that sits at the bottom of the UFS drivers and above the disk drivers to cache synchronous writes. When used on a news machine, I have witnessed the unpack rate double, and the efficiency of fastrm go straight through the roof. Since it only caches synchronous writes, the small ammount of RAM can be put to maximum use, and since it's battery backed, it's no less safe than if it were written straight to disk (a 'dirty reboot' results in the dirty buffers being flushed on the first disk access). Presuming for the moment that it would not violate any patents to do this, would it not be a nice thing to add to FreeBSD? Surely it would be no big trick to make an ISA card with 1M of battery backed static RAM. The tricky part would be the driver, but anything that has its difficult part in software can't be all that bad. :-) -- Nick Sayer <nsayer@quack.kfu.com> | "Now class, put away your weapons N6QQQ @ N0ARY.#NORCAL.CA.USA.NOAM | and open your TV Guides." +1 408 249 9630, log in as 'guest' | URL: http://www.kfu.com/~nsayer/ | -- Dogbert