ayi <p>When you setup a site on IIS it defaults the worker process to recycle every 1740 minutes (29 hours). Why an odd number like 29 hours and not, for example, 24 or 48 hours?</p>
ayi_2 <p>At Tech Ed 2003, the presenter was asked this question, and the answer was that they wanted an irregular cycle to prevent it from occurring on a daily boundary (e.g. to distinguish from other daily tasks scheduled on the server / domain).</p> <p>The site <a href="http://davybrion.com/blog/2010/06/why-do-we-recycle-our-application-pools/">here(Link dead)</a> speculated:</p> <blockquote></blockquote> <p>… (29 is the) first prime after 24, allowing it to have the least chance occurring in a regular pattern with any other server process; easing the investigation into problems</p> <p><a href="https://weblogs.asp.net/owscott/why-is-the-iis-default-app-pool-recycle-set-to-1740-minutes">Another site</a> appears to confirm this :</p> <blockquote></blockquote> <p>(<a href="https://blogs.iis.net/wadeh">Wade Hilmo</a>) suggested 29 hours for the simple reason that it’s the smallest prime number over 24. He wanted a staggered and non-repeating pattern that doesn’t occur more frequently than once per day</p>
