<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Interesting discussion, but you either need to use failure suspectors, which are different to failure detectors, or quantum mechanics. I suppose the only other choice is omniscience, but I don't know how to do that ;-)<div><br></div><div>Mark.</div><div><br></div><div><br><div><div>On 18 Feb 2011, at 00:59, Paolo Romano wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><blockquote cite="mid:2BB692FA-DEF5-4812-9C82-C5273266F773@ncl.ac.uk" type="cite"><div>And we both know there is no such thing, unless you want to get into the world of quantum mechanics :-)</div></blockquote><br>....still there are many real systems that are actually designed assuming perfect failure detection... possibly relying on some dedicated hardware mechanism (which encapsulate the perfect failure detection assumption) to enforce accuracy by forcing suspected nodes to shut down falsely suspected nodes, e.g.<span class="Apple-converted-space"> </span><a class="moz-txt-link-freetext" href="http://en.wikipedia.org/wiki/STONITH">http://en.wikipedia.org/wiki/STONITH</a>.</span></blockquote></div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>---</div><div>Mark Little</div><div><a href="mailto:mlittle@redhat.com">mlittle@redhat.com</a></div><div><br class="webkit-block-placeholder"></div><div>JBoss, by Red Hat</div><div>Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom.</div><div>Registered in UK and Wales under Company Registration No. 3798903 Directors: Michael Cunningham (USA), Charlie Peters (USA), Matt Parsons (USA) and Brendan Lane (Ireland).</div></div><div><br></div></div></span><br class="Apple-interchange-newline"></span><br class="Apple-interchange-newline">
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