On Sun, 2023-02-05 at 13:17 -0600, Russ Anderson wrote: > > Gave the v6 patchset a try on a system with 1920 logocal cpus > (sixteen 60 core Sapphire Rapids sockets with Hyperthreadding > enabled). > > Without the patchset it took 71 seconds to start all the cpus. > With the v6 patchset it took 14 seconds to start all the cpus, > a reduction of 57 seconds.  That is impressive. > > Full boot, to root login prompt, without patches takes 223 seconds. > This patchset reduces the full boot time by 57 seconds, a 25% > reduction. Nice; thanks for testing. Is that with just the "part1" patch series which has been posted, or also with the 'parallel part 2' still taking shape in the tree at https://git.infradead.org/users/dwmw2/linux.git/shortlog/refs/heads/parallel-6.2-rc6 I believe Usama said the second phase of parallelism didn't really help much in terms of overall timing? Confirming that *without* all the debug prints would be interesting. And we can look for what still *could* be made parallel.