Path: utzoo!attcan!uunet!husc6!rutgers!gatech!rebel!george
From: george@rebel.UUCP (George M. Sipe)
Newsgroups: comp.databases
Subject: Re: OLTP, New releases of Oracle and Rd
Message-ID: <42151@rebel.UUCP>
Date: 6 Aug 88 17:31:12 GMT
References: <376@cullsj.UUCP> <28400002@urbsdc>
Reply-To: george@rebel.UUCP (George M. Sipe)
Organization: Tolerant Systems, Atlanta GA
Lines: 32

In article <28400002@urbsdc> kworrell@urbsdc.Urbana.Gould.COM writes:
>This brings up an interesting question.  Where should mirrorred
>disks be implemented, in the DBMS or in the OS?
>
>Gould has implemented mirrored disks in the OS making explicit
>mirroring by the DBMS unnecessary.

and

In article <254@quintus.UUCP> jbeard@quintus.uucp (Jeff Beard) writes:
>Your criteria is the bread and butter of the Tandem Non-stop system.
>Suggest you contact a vendor representative for documentation.

Well, if we are going to be commercial here, Tolerant Systems offers
multiple disk mirroring called n-plexing.  It allows for use of
dissimilar media, automatic revives, and other features.  Additionally
TX is Unix - unlike Tandem.  Like Tandem, it is fault-tolerant to any
single point of hardware or software failure, loosely coupled, distributed,
and a single system image in a global name space.

Of use to db systems, it provides kernel implemented transaction framing,
255 fds per process, O_SYNC on open/fcntl, "crash proof" filesystems,
extent based files (up to 8MB per extent) on a per file basis, and many
other features.  Raw I/O is totally unnecessary, for instance.

You compare this to Gould and Tandem and draw your own conclusions.
Of course, like any vendor, we are thrilled to send you more info.

-- 
George M. Sipe,		Phone: (404) 662-1533
Tolerant Systems, 6961 Peachtree Industrial, Norcross, GA  30071
UUCP: ...!{decvax,hplabs,linus,rutgers,seismo}!gatech!rebel!george