home *** CD-ROM | disk | FTP | other *** search
- Newsgroups: comp.databases
- Path: sparky!uunet!usc!sdd.hp.com!hpscdc!cupnews0.cup.hp.com!dhepner
- From: dhepner@cup.hp.com (Dan Hepner)
- Subject: Re: Hot Standby DBMS's
- Sender: news@cupnews0.cup.hp.com
- Message-ID: <BtAMG4.3rF@cup.hp.com>
- Date: Thu, 20 Aug 1992 17:40:52 GMT
- References: <BtA7DE.JrG@world.std.com>
- Organization: Hewlett-Packard
- X-Newsreader: Tin 1.1scd1 PL4
- Lines: 16
-
- From: edwards@world.std.com (Jonathan Edwards)
-
- >Given a CICS-like environment, you propose splitting all input transactions
- >(3270 screens) across two systems (i infer).
- >One of these system is 'muted' so that its outputs are
- >supressed. This is not quite perfect, though, due to the possibility of
- >timing differences on the two systems. Any transaction mix that leads to
- >lock races could have different outcomes on the two systems due to random
- >timing differences.
-
- Since all locks need to be obtained on both systems before the
- transaction is eventually committed, lock race conditions (defective
- design) result in deadlocks. The system as a whole remains perfectly
- serialized.
-
- Dan Hepner
-