On 21 March 2012 19:19, John Baldwin <j...@freebsd.org> wrote: > On Tuesday, March 20, 2012 11:37:57 am Sergey Kandaurov wrote: >> On 22 November 2011 19:29, Mark Saad <nones...@longcount.org> wrote: >> > Hello All >> >> [found this mail in my drafts, not sure if my answer is still useful] >> >> > I want to get to the bottom of a warning in dmesg. On 7.2-RELEASE and >> > 7.3-RELEASE I have seen the following warning in dmesg. >> > >> > Approaching the limit on PV entries, consider increasing either the >> > vm.pmap.shpgperproc or the vm.pmap.pv_entry_max sysctl. >> > >> > So looking around I see a few posts here and there about how to tune >> > the sysctls to address the warning however I am not 100% sure what >> > each value does. >> > It appears changing vm.pmap.shpgperproc affects the value of >> > vm.pmap.pv_entry_max . Can someone explain the relationship of the two >> > sysctls. Also >> >> This is how they are calculated. >> >> pv_entry_max = shpgperproc * maxproc + cnt.v_page_count; >> >> and, respectively, >> >> shpgperproc = (pv_entry_max - cnt.v_page_count) / maxproc; >> >> So, changing one sysctl will change another and vice versa. >> >> > what pitfalls of changing them are. >> >> Not known to me (on amd64 platform). >> I have had vm.pmap.shpgperproc=15000 on 8.1 amd64 with 4G RAM >> to make some badly written commercial software to work until it >> was decommissioned to the scrap. > > FYI, Alan just removed this warning and the associated sysctls from HEAD > yesterday because they were made obsolete several years ago. I think they are > obsolete even on 7. Certainly on 8.
Yep, and since switching to direct map (somewhere around 7.x on amd64?) made PV entry limit factually obsolete, this is really cool. -- wbr, pluknet _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
