Hello,
About two years ago, there was some talk on the Busybox mailing-list about the need for a version of "mdev" that would not use a separate process for every uevent (as a hotplug manager does) but that would act as a daemon, able to handle a series of uevents - typically read from the netlink. One of the goals of such a program was to reduce boot time on slow / resource-constrained devices that don't like creating hundreds of processes at the same time - especially when they contend for a sequence number. I took a quick look at the time, but came to the conclusion that the way mdev was coded made it very difficult. Basically, mdev gets its uevent variables from the environment, then reads and processes its config file, performing actions as it goes. A quick hack to add "daemon mode" support to mdev would still make it process the config file for every event, similarly to what "mdev -s" does; this would remove the forks but still be pretty inefficient, not to mention particularly ugly. To implement "daemon mode mdev" in a clean way, a full rewrite was needed. So I shelved the idea at the time. Until now. mdevd is a uevent manager reading a sequence of uevents and handling them without forking, that understands the full /etc/mdev.conf format. "mdevd-coldplug | mdevd" is equivalent to "mdev -s". "mdevd-netlink | mdevd" is a daemon that listens to the netlink and processes uevents sequentially, without the need for mdev.seq hacks coming from the kernel spawning hotplug managers in parallel. You can find it here: https://skarnet.org/software/mdevd/ git://git.skarnet.org/mdevd https://github.com/skarnet/mdevd Since it's a full rewrite with a very different architecture from mdev and little code reusability with the rest of Busybox, it did not make sense to include it in Busybox, which is why it's provided as a separate package. Bug-reports welcome. mdevd is still considered beta for some functionality I could not extensively test, such as firmware loading. If your setup uses firmware loading or otherwise obscure mdev features, I'm especially interested in your reports and/or comments. (mdevd comes with a dry run mode, so you don't have to be a reckless cowboy to test it.) Enjoy, -- Laurent _______________________________________________ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox
