On Thu 20 Jul 2017 at 19:13, Martin Weber <[email protected]> wrote:
> Hi list, > > my plugins adds a build wrapper that starts and stop a daemon (similar to > xvfb > [1] plugin). > Only one daemon instance can be run at a time on a single node, so I want > to > block job execution automatically, without forcing my users to install and > configure Throttle Concurrent Builds plugin [2]. > > I tried to implement a QueueTaskDispatcher that blocks if a job is running > that also has my plugin wrapper enabled. It works mostly, but if I have 3 > jobs > with my wrapper enabled in the queue and 2 executors on the node, *both* of > the 2 blocked jobs start execution after the first job has finished. Yep because both jobs transition at the same time. What you need to do is keep track of if you let a job through and wait say 100ms before letting another go through (but round-robin which one you pick) A cheap way might be to be use a 5% probability of letting a job through when none are running... That gives you a 1:400 chance of two jobs in the same "round" and most jobs should start in under 1 second if they can while avoiding having to deal with concurrency issues so much. If 1:400 is too high, you'll need to bite the bullet and sort out the concurrency to determine when a round starts and then only allow one per round to be unblocked (pick a different one each round) > > > Can anyone point me to the right direction to solve this (allow only one > running job with my wrapper enabled per node)? > > TIA, > Martin > > [1] https://plugins.jenkins.io/xvfb > [2] https://plugins.jenkins.io/throttle-concurrents > > -- > Cd wrttn wtht vwls s mch trsr. > > > -- > You received this message because you are subscribed to the Google Groups > "Jenkins Developers" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/jenkinsci-dev/6641805.XLH7yz7z48%40linux > . > For more options, visit https://groups.google.com/d/optout. > -- Sent from my phone -- You received this message because you are subscribed to the Google Groups "Jenkins Developers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jenkinsci-dev/CA%2BnPnMy7tUgQxvyHPXx2nYZQ9DZ6YN3Yd4DDHZYbAiHz%2BACT%3DA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
