On Fri, Feb 27, 2009 at 11:11 AM, John Baldwin <j...@freebsd.org> wrote:
> On Friday 27 February 2009 11:26:25 am Igor Sysoev wrote: > > On Fri, Feb 27, 2009 at 10:26:15AM -0500, John Baldwin wrote: > > > > > On Friday 27 February 2009 8:08:30 am Igor Sysoev wrote: > > > > Is anyone able to boot kernel with recently merged superpage support > ? > > > > I have csup'd world to > > > > *default date=2009.02.26.23.59.59 > > > > then rebuild world and kernel does not boot: > > > > > > > > FreeBSD 7.1-STABLE #4: Fri Feb 27 11:59:13 MSK 2009 > > > > XXXXXXXXXXXXXXXXXXXXX > > > > kernel trap 12 with interrupts disabled > > > > > > > > > > > > Fatal trap 12: page fault while in kernel mode > > > > cpuid = 0; apic id = 00 > > > > fault virtual address = 0x0 > > > > fault code = supervisor read data, page not present > > > > instruction pointer = 0x8:0xffffffff803b1d80 > > > > stack pointer = 0x10:0xffffffff80686ce0 > > > > frame pointer = 0x10:0xffffffff80686d00 > > > > code segment = base 0x0, limit 0xfffff, type 0x1b > > > > = DPL 0, pres 1, long 1, def32 0, gran 1 > > > > processor eflags = resume, IOPL = 0 > > > > current process = 0 () > > > > trap number = 12 > > > > panic: page fault > > > > cpuid = 0 > > > > > > > > And the message is cycled. The kernel does not boot despite > > > > vm.pmap.pg_ps_enabled value. > > > > > > This should now be fixed, apologies for the breakage. :( > > > > Thank you, your commit has fixed the bug. > > > > Now I have > > > > $sysctl vm.pmap.pde > > vm.pmap.pde.promotions: 518 > > vm.pmap.pde.p_failures: 4534 > > vm.pmap.pde.mappings: 0 > > vm.pmap.pde.demotions: 423 > > > > Does this mean that (518 - 423) * 2 = 190M are mapped via 2M pages ? > > I don't think that includes the direct map which uses 2M pages. I think > your > conclusion is correct, but alc@ would know for sure. > > -- > John Baldwin > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org" > These counts are cumulative. So, they don't really provide you with an instantaneous number of the active 2MB page mappings. Moreover, when a 2MB page mapping is destroyed in its entirety, for example, when exit()ing a process, that does not trigger a demotion. In other words, a promoted 2MB page mapping can cease to exist without a demotion occurring. You are correct that in RELENG_7 these counts don't say anything about the direct map. Alan _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
