On Tue, Oct 21, 2008 at 13:48, Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx> wrote: > Kay Sievers wrote: >> On Tue, Oct 21, 2008 at 12:11, Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx> wrote: >> >>> Allocate udev_device->envp lazily >>> >>> It's a pity to allocate 128 words when we don't need them. >>> Measured 2% _user_ cpu time reduction on EeePC coldplug. >> >> Any idea what might take 2% here? We don't do anything if the envp >> isn't used. We do almost the same thing with or without the patch >> besides that "struct udev_device" is 1016 bytes smaller now, and we >> malloc() it. > oprofile said malloc() went down by about that much. I measured on top > of threaded udevd, so I might be unlucky and chasing overheads you don't > see in the single-threaded implementation :). > > By rights it should reduce memset() (or calloc now). And it might help > with caching, because the array effectively splits udev_device in two. Applied. Thanks, Kay -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
