On 2015-07-29 11:28:57, Jamie Strandboge wrote: > On 07/29/2015 11:09 AM, Tyler Hicks wrote: > > On 2015-07-29 11:25:27, Alberto Mardegan wrote: > >> On 07/29/2015 07:07 AM, Tyler Hicks wrote: > > >>> The exec() will need to occur after special process initialization > >>> such as setting rlimits, configuring cgroups, etc., but before > >>> attempting to preload any libraries. > >>> > >>> I've prototyped the difference with a simple proof-of-concept of a > >>> booster daemon and app program and the exec() slows down things a > >>> considerable amount. Any benchmarks should definitely include such > >>> a change in order to not get any hopes up by looking at the > >>> non-exec()ing benchmark numbers. > >> > >> But the exec() does not necessarily need to load the application, > >> right? It could happen when the user has not yet chosen which > >> application to start, and instead of executing an app, it could exec() > >> into a loader process which does all library preloading and > >> initializing, and then (when the user launches an app) dlopen the app, > >> close any unneeded file descriptors, call aa_change_profile and > >> finally run main(). Then of course it would have to quit, and not be > >> reused. > > > > Yes, exactly! > > > >> This would still preserve the ASLR, wouldn't it? > > > > Yes. I think there will still be plenty of speed benefits. I don't think > > the memory footprint benefits of the booster processes will be nearly as > > good, though. My whole point is that it is worth benchmarking because I > > think we'll still good performance. > > > I think it is important to note (and please correct me if I am wrong! :) that, > today, there is no memory footprint benefit to lose because, today, we have a > full fork/exec of each app. Therefore if we can realize 'plenty of speed > benefits' as Tyler believes we can (and that people should benchmark), that > is a > complete 'win' for the platform.
Ah, yes, that's a great point. Thanks for mentioning that. Tyler > > -- > Jamie Strandboge http://www.ubuntu.com/ > > -- > Mailing list: https://launchpad.net/~ubuntu-phone > Post to : ubuntu-phone@lists.launchpad.net > Unsubscribe : https://launchpad.net/~ubuntu-phone > More help : https://help.launchpad.net/ListHelp
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-- Mailing list: https://launchpad.net/~ubuntu-phone Post to : ubuntu-phone@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-phone More help : https://help.launchpad.net/ListHelp
