On Wednesday, March 21, 2012 4:20:17 pm Mark Saad wrote: > On Wed, Mar 21, 2012 at 12:39 PM, Sergey Kandaurov <pluk...@gmail.com> wrote: > > 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 > > Interesting so this warning is relevant in 7.x ?
No, looks like it was obsolete starting with 7.0. -- John Baldwin _______________________________________________ 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"
