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<p>Spread currently uses the wall clock time for all of its time based calculations. If you only move the clock a little, then you probably won't have any issues, although I'm not 100% sure. If you drastically jump the clock forward, then I can see major issues as suddenly the already scheduled timeouts will take forever to fire. If you drastically jump the clock backwards, then a lot of timeouts will fire prematurely, which might cause a spurious partition or something, but the system would probably then return to normal operations immediately thereafter.</p>
<p><br></p>
<p>The events system definitely should be moved over to using a monotonic clock on whatever platforms such a service is available. We would like to do this sometime in the future, but if you experiment with it and get something to work and want to contribute it back, then that would be great.</p>
<p><br></p>
<p>Cheers!</p>
<p>John</p>
<p><br></p>
<p>---</p>
<p>John Lane Schultz</p>
<p>Spread Concepts LLC</p>
<p>Phn: 443 838 2200 </p>
<p>Fax: 301 560 8875</p>
<p><br></p>
<p>Friday, May 8, 2009, 11:19:23 AM, you wrote:</p>
<p><br></p>
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<p><span class=rvts6>></span></p>
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<p><span class=rvts7>Hi,</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>I have a single spread daemon and a bunch of programs communicating via spread messages </span></p>
<p><span class=rvts7>through this daemon. All programs and the daemon are running on the same machine.</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>From previous mails on this list, I know that people have had problems with message </span></p>
<p><span class=rvts7>delivery when they have changed the clock, via settimeofday and even NTP.</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>But I'm not sure if this can only occur when there are multiple daemons or if it can happen</span><span class=rvts8> </span></p>
<p><span class=rvts7>in my case too. Browsing through the code in events.c, it looks as it could happen in my case </span></p>
<p><span class=rvts7>too, although the probability is perhaps small.</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>Has someone a testprogram/argument proving that this is either true or false?</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>I'm thinking about changing the gettimeofday call in E_get_time to something that is not</span><span class=rvts8> </span></p>
<p><span class=rvts7>affected by some external source setting the time, for example, clock_gettime(CLOCK_MONOTONIC).</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>Has someone done something similar before?</span><span class=rvts8> </span></p>
<p><br></p>
<p><span class=rvts7>Cheers,</span><span class=rvts8> </span></p>
<p><span class=rvts7>Drago</span></p>
<p><br></p>
<p><span class=rvts7>_______________________________________________________________________________________________________________ </span></p>
<p><span class=rvts7>This e-mail communication (and any attachment/s) may contain confidential or privileged information and is intended only for the individual(s) or entity named above and to others who have been specifically authorized to receive it. If you are not the intended recipient, please do not read, copy, use or disclose the contents of this communication to others. Please notify the sender that you have received this e-mail in error by reply e-mail, and delete the e-mail subsequently. Please note that in order to protect the security of our information systems an AntiSPAM solution is in use and will browse through incoming emails. </span></p>
<p><span class=rvts7>Thank you. </span></p>
<p><span class=rvts7>_________________________________________________________________________________________________________________ </span></p>
<p><br></p>
<p><span class=rvts7>Ce message (ainsi que le(s) fichier(s)), transmis par courriel, peut contenir des renseignements confidentiels ou protégés et est destiné à l’usage exclusif du destinataire ci-dessus. Toute autre personne est, par les présentes, avisée qu’il est strictement interdit de le diffuser, le distribuer ou le reproduire. Si vous l’avez reçu par inadvertance, veuillez nous en aviser et détruire ce message. Veuillez prendre note qu'une solution antipollupostage (AntiSPAM) est utilisée afin d'assurer la sécurité de nos systèmes d'information et qu'elle furètera les courriels entrants.</span></p>
<p><span class=rvts7>Merci. </span></p>
<p><span class=rvts7>_________________________________________________________________________________________________________________ </span></p>
<p><br></p>
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