On 02/02/2018 02:42 AM, Eric W. Biederman wrote: > Jan H. Schönherr <jscho...@amazon.de> writes: > >> Give the administrator the ability to trade kexec safety for kexec speed >> by disabling the digest calculation/verification for regular kexecs. >> >> The behavior of kexec-on-crash is not touched. > > The performance of the digest caculation is acceptable on 386s. Or it > was years ago when I tested it on a 386. What is the problem you are > having. > > Is there something silly like a cache disable in your configuration?
Last time I measured, this patch reduced the time until the system is responsive again after a kexec by about 50 ms to 100 ms in my setups. That seems to be about the right time for enabled caches, judging from a quick sha256sum on the command line and the kernel sizes I'm working with. These 50 ms to 100 ms are a noticeable fraction of the total kexec time and they are easy to avoid -- compared to some other time sinks in the Linux boot process. Regards Jan _______________________________________________ kexec mailing list firstname.lastname@example.org http://lists.infradead.org/mailman/listinfo/kexec