On Thu, 17 Jan 2013 08:43:21 +0000 Fiedler Roman <Roman.Fiedler@ait.ac.at> wrote: > Hello List, > > What would be the most suitable solution to avoid high load/overlong cron job execution for hourly/daily/... jobs? When using similar vservers, all of them would start those jobs at the same time. depends (imho): providing/using a hosting service and want guarantees? cgroup blkio controller. cooperative administration of vservers? nice and/or ionice. "poor man's" approach? ${RANDOM}. i haven't tested/used the cgroup's blkio controller, but in theory that's what it's suppose to do (cgroup's other controllers work for me). > Currently I'm using a script on the host to run no more than N guest hourly/daily/... jobs in parallel. i presume you are administering them on your own and/or somebody else's behalf and can schedule them cooperatively. i wouldn't expect this level of cooperation from/among users of a hosting service (ie system administration by committee). i do cooperative scheduling of some jobs and do it sequentially on each vserver from the host, but that's because i'm the only administrator/user of my vservers and host them myself (and it's simple/stupid). if i was using a vserver provided by someone else (eg hosting service), then i would either expect them to provide guaranteed io throughput (just like for cpu and memory) or i'd randomize it myself (based on how much i was paying; poor man's solution). i've already seen randomizing as a solution to not overloading resources among controlled but uncoordinated systems: system/virus updates are randomly staggered on corporate desktops so as to not overload the server and/or congest the network. corey -- undefined@pobox.com > Is that a good solution to the problem? > If not, what would be better? > If yes, add the script to vserver-utils? Apart from that, the current approach allows the host to detect, when all guest dailies have completed, so that it can start actions that need to be run after all those e.g. guest backup-prepare before backup start on host. > > Roman >