It seems sto me that what would be cool is some kind of distributed sequencer, such that the individual linodes on each machine have a way of communicating and not running cron jobs at the same time. It could be a command, I will call it distseq for purposes here. It would work like this:

Instead of running a command like "updatedb" at a certain time, run something like "distseq --node linode31 --command "updatedb -blah"".

This distseq command would: 1) contact some server 2) ask server if its ok to run the command now, wait until it says its ok 3) run the command 4) report to server that its done. If 1 failed (network problem etc), just run the command anyway.

There woudl be a server component, call it distseqd, running somewhere, possibly the host linode or just one global host. It would 1) wait for connections 2) when a connection is received, respond by either marking command as finished or requested. In parallel with that it would 1) Check for nodes that are not running a job 2) If any outstanding requests for that node, send message to node saying its ok to run command.

Something along those lines. Is there someting out there that does this? It just seems that the overhead of running 32 or whatever intensive jobs simulataneously on a 2-processor machine will always be a problem, even with more efficient OS implementations. I just timed my updatedb, it only takes like 30 seconds, so running like 32 of em one after the other wouldn't take more than half an hour.

Is there something out there that already does this? Seems like something that all UML implementors would have to deal with. If there isn't something out there, and if there is interest, I can try to code something up. I would ask for someone to audit my code, since there would be obvious security issues with someting like this and I wouldn't want to open holes.

There has been no real improvement in the spikes. When are we going to get kernel 2.6 on host5???