Issue status update for http://drupal.org/node/19173 Project: Drupal Version: cvs Component: base system Category: feature requests Priority: normal Assigned to: robertDouglass Reported by: robertDouglass Updated by: Chris Johnson Status: patch It does seem like a good idea to allow running different cron tasks at different intervals, so as to be efficient and reduce web server loads. There is little point in running tasks that do not need to be run. Many cron tasks only need to be run once to a few times per day. Note also that cron job scheduling on most Unix-variants is only within a +/- 1 minute range, so trying to run a cron program every 2 minutes is approaching the crumbling edge of being "on time." Chris Johnson Previous comments: ------------------------------------------------------------------------ March 20, 2005 - 04:08 : robertDouglass Attachment: http://drupal.org/files/issues/cronpatch.txt (1.99 KB) Some sites need fine grained timing for cron runs. For example, a site that relies heavily on moblogging, mailhandler or any other email based function would want to connect with the email server pretty often, say ever 2-5 minutes. On another site I'm working on we generate flat files for all of a certain node type on a regular basis, though not every 2-5 minutes. Thus the need for cron tasks on different schedules. This patch allows you to make a list of modules to either include or exclude when running cron, so that several cron tasks for one site can be defined. The default behavior in the absence of both parameters is to run all, so the patch preserves backwards compatibility. * Examples: * * runs all hooks * http://mysite.com/cron.php * * runs all hooks except the search and aggregator modules * http://mysite.com/cron.php?exclude=search,aggregator * * runs only search, archive and aggregator modules * http://mysite.com/cron.php?includ=search,archive,aggregator ------------------------------------------------------------------------ March 23, 2005 - 15:23 : Dries Isn't it possible to run all cron functions every 2-5 minutes? The impact of that should be minimal. ------------------------------------------------------------------------ March 23, 2005 - 15:33 : moshe weitzman an alternative approach is to make a quick PHP page which simply calls mailhandler_cron and any others that need to be called more frequently than normal. then call that php page from cron every couple minutes ... not so sure this complexity is worth having. ------------------------------------------------------------------------ March 24, 2005 - 01:32 : robertDouglass Whether or not this "complexity" is needed depends a lot on what you expect to do with cron. As soon as one starts aggregating not tens but several hundred RSS feeds or more, it is impossible to run cron every 2 minutes. Yet if the site depends on mailhandler keeping user moblog submissions current, 2 minutes is already about the maximum latency time acceptable. Thus the need for crons on different schedules. In terms of usage, writing ?include=mailhandler,search,event isn't so complex. On the code level, splitting that list on comma and looping over the resultant array also isn't really that complex. The patch defaults to normal behavior for people who don't need the feature, and I've seen more than one site that had to solve this problem. ------------------------------------------------------------------------ March 24, 2005 - 04:48 : Robert Castelo Could different cron runs be set to run different tasks based on a cron ID number.... For instance, set up 3 separate cron to run every hour, each one calls the cron.php page including a number variable which runs a certain set of tasks. An Admin control panel would list all cron tasks and allow administrators to split them into separate cron runs based on the number variable passed to the script when calling cron.php. ------------------------------------------------------------------------ March 24, 2005 - 05:24 : robertDouglass Robert, the id parameter is already a practical necessity for this patch if cron_busy is to be effective. I'm open to suggestions as to how we would track various cron tasks and whether they are busy. First things first, though: does anyone except me need this? I'm not going to program an admin-configurable cron mechanism unless there is demand for it. Furthermore, such a system would really be incomplete unless there were some actual mechanism for setting these cron runs up from the admin interface as well. This wouldn't be such a bad idea, I know a lot of people who still type /cron.php into their browser every day or so to updated thier sites (yes I've mentioned poormanscron). Anyway, first reactions to this patch have been cold, so maybe nobody wants it. ------------------------------------------------------------------------ March 24, 2005 - 05:39 : Robert Castelo +1 from me. I'll be needing something like this once my email newsletter is released and starts hogging cron runs.