Date: Tue, 3 Feb 2004 13:05:16 -0800 (PST) From: Julian Elischer <julian@elischer.org> To: Sridhar Chellappa <schellap@spinnakernet.com> Cc: freebsd-hackers@freebsd.org Subject: Re: Kernel Virtual Address Space Message-ID: <Pine.BSF.4.21.0402031304050.88161-100000@InterJet.elischer.org> In-Reply-To: <402004C2.7080309@spinnakernet.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 3 Feb 2004, Sridhar Chellappa wrote: > Julian Elischer wrote: > > > > >On Tue, 3 Feb 2004, Sridhar Chellappa wrote: > > > >>Sridhar Chellappa wrote: > >> > >>>As part of the Bootup sequence, I see create_pagetables allocate only > >>>30 Pages for Page Table entries in non-PAE mode and 120 pages in PAE > >>>mode. Does this mean that all the kernel mode entities get only 4 * 30 > >>>* 1024 * 1024 = 120 MB worth of Address Space ? Can I tune the kernel > >>>virtual address space by just changing the "NKPT" define in pmap.h ? > >>> > >>>Also, I heard that the BSD kernel(atleast from 5.1 onward) itself is > >>>pre-emptible and none of the kernel threads have a cpu affinity. How > >>>do I change the behaviour to make the kernel non-preemptible and tie > >>>kernel-threads to a particular CPU ? > >>> > >>>Sridhar. > >>> > >>>_______________________________________________ > >>>freebsd-hackers@freebsd.org mailing list > >>>http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > >>>To unsubscribe, send any mail to > >>>"freebsd-hackers-unsubscribe@freebsd.org" > >>> > >>Under Linux, all kernel threads share the same "Kernel" Virtual Address > >>Space. Is it the same under freeBSD ? If it is not, then what sort of > >>Stuff gets put into the "Kernel" Virtual Address Space? > >> > > > >The simple answer is: "yes they do". > > > >> > >> > >>_______________________________________________ > >>freebsd-hackers@freebsd.org mailing list > >>http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > >>To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.org" > >> > Is it possible for freeBSD kernel threads to have their own private > virtual address space ?? Anything is theoretically possible.. each kernel 'thread' is at this time a separate kernel process and can thus have it's own page tables etc. the fact that we don't do that doesn't make it theoretically impossible :-) > > >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.21.0402031304050.88161-100000>