On Mon, Jun 10, 2013 at 10:37:36PM +0300, Konstantin Belousov wrote: > On Mon, Jun 10, 2013 at 12:02:20PM -0500, Alan Cox wrote: > > On 06/10/2013 06:08, Olivier Houchard wrote: > > > On Mon, Jun 10, 2013 at 06:55:47AM +0300, Konstantin Belousov wrote: > > >> On Sun, Jun 09, 2013 at 10:51:12PM +0000, Olivier Houchard wrote: > > >>> Author: cognet > > >>> Date: Sun Jun 9 22:51:11 2013 > > >>> New Revision: 251586 > > >>> URL: http://svnweb.freebsd.org/changeset/base/251586 > > >>> > > >>> Log: > > >>> Increase the maximum KVM available on TI chips. Not sure why we > > >>> suddenly need > > >>> that much, but that lets me boot with 1GB of RAM. > > >> I suspect that the cause is the combination of limited KVA and > > >> lack of any limitation for the buffer map. I noted that ARM lacks > > >> VM_BCACHE_SIZE_MAX after a report from mav about similar (?) problem a > > >> day ago. > > >> > > >> In essence, the buffer map is allowed to take up to ~330MB when no > > >> upper limit from VM_BCACHE_SIZE_MAX is specified. > > > > > > Hi Konstantin, > > > > > > Thanks for the hint ! > > > It seems only i386 and sparc64 sets it, what would be a good value, 200M, > > > as > > > it is on i386 ? > > > > > > > Since there are many arm platforms with less than 1 GB of kernel virtual > > address (KVA) space, VM_BCACHE_SIZE_MAX should be made to scale down > > from 200 MB with the available KVA space. See how VM_KMEM_SIZE_MAX is > > currently defined on arm. > > In fact, Ithink it does not make much sense to scale the buffer cache up. > It is mostly wasted space now. As I measured it, on typical load you > have only 10-20% of instantiated buffers mapped. > > Alexander Motin reported that he tested the equivalent of the following > change. With it committed, I think that r251586 could be reverted. > > diff --git a/sys/arm/include/param.h b/sys/arm/include/param.h > index 9ffb118..5c738c2 100644 > --- a/sys/arm/include/param.h > +++ b/sys/arm/include/param.h > @@ -128,6 +128,11 @@ > #define USPACE_SVC_STACK_BOTTOM (USPACE_SVC_STACK_TOP - 0x1000) > #define USPACE_UNDEF_STACK_TOP (USPACE_SVC_STACK_BOTTOM - 0x10) > #define USPACE_UNDEF_STACK_BOTTOM (FPCONTEXTSIZE + 10) > + > +#ifndef VM_BCACHE_SIZE_MAX > +#define VM_BCACHE_SIZE_MAX (128 * 1024 * 1024) > +#endif > + > /* > * Mach derived conversion macros > */
I tested it with my changes reverted and it works indeed, so I'm fine with this being committed and my changes being reverted. Regards, Olivier _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
