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From: jackson@uiuccsb.UUCP
Newsgroups: net.arch
Subject: Re: MTBF of Crays. - (nf)
Message-ID: <5600010@uiuccsb.UUCP>
Date: Thu, 26-Apr-84 12:42:00 EST
Article-I.D.: uiuccsb.5600010
Posted: Thu Apr 26 12:42:00 1984
Date-Received: Sat, 28-Apr-84 10:57:44 EST
References: <6753@umcp-cs.UUCP>
Lines: 14
Nf-ID: #R:umcp-cs:-675300:uiuccsb:5600010:000:522
Nf-From: uiuccsb!jackson    Apr 26 11:42:00 1984

#R:umcp-cs:-675300:uiuccsb:5600010:000:522
uiuccsb!jackson    Apr 26 11:42:00 1984

The first Cray-1 was delivered to Los Alamos Scientific Laboratory in 1976. 
This machine did not have error correction circuitry in its memory -- only
error detection.  It had a MTBF of 4 hours -- this is the time that you
were probably referring to.  Cray's now have SECDED (single error-correcting
double error-detecting) logic like any well designed machine should.  I'm not
sure what the MTBF of the Cray-1 is now, but it sure is a LOT more than
4 hours!


Dan Jackson
UUCP:    {pur-ee!ihnp4}!uiucdcs!uiuccsb!jackson