hi, can you someone explain why i have only ~3GB memory available with xen 3.0.2 (kernel 2.6.16.16) 2339MB HIGHMEM available. 831MB LOWMEM available. --config-- # CONFIG_NOHIGHMEM is not set CONFIG_HIGHMEM4G=y # CONFIG_HIGHMEM64G is not set CONFIG_VMSPLIT_3G=y # CONFIG_VMSPLIT_3G_OPT is not set # CONFIG_VMSPLIT_2G is not set # CONFIG_VMSPLIT_1G is not set CONFIG_PAGE_OFFSET=0xC0000000 CONFIG_HIGHMEM=y ---cut-- HW Supermicro 2x xeon 4x1024 ram with distro kernel (rhel 2.6.9-34smp) i have full 4GB mem thanks --------------------------------------- Marek Cervenka ====================================== _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
recompiled, PAE enabled (XEN) System RAM: 4095MB (4193308kB) (XEN) Xen heap: 10MB (10412kB) (XEN) Using scheduler: Simple EDF Scheduler (sedf) (XEN) PAE enabled, limit: 16 GB 3200MB HIGHMEM available. 727MB LOWMEM available. are there "performance" statistics for PAE vs nonPAE ?> can you someone explain why i have only ~3GB memory available with xen 3.0.2 > (kernel 2.6.16.16) > > 2339MB HIGHMEM available. > 831MB LOWMEM available. > > --config-- > # CONFIG_NOHIGHMEM is not set > CONFIG_HIGHMEM4G=y > # CONFIG_HIGHMEM64G is not set > CONFIG_VMSPLIT_3G=y > # CONFIG_VMSPLIT_3G_OPT is not set > # CONFIG_VMSPLIT_2G is not set > # CONFIG_VMSPLIT_1G is not set > CONFIG_PAGE_OFFSET=0xC0000000 > CONFIG_HIGHMEM=y > ---cut-- > > HW Supermicro 2x xeon 4x1024 ram > > with distro kernel (rhel 2.6.9-34smp) i have full 4GB mem > > thanks > > --------------------------------------- > Marek Cervenka > ======================================> > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >--------------------------------------- Marek Cervenka Centrum Vypocetni Techniky CVT - http://cvt.fpf.slu.cz FPF SLU OPAVA - http://www.fpf.slu.cz LCNA - http://lcna.slu.cz ====================================== _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
To be able to see more than about 3.5GB of actual RAM, you need to enable HIGHMEM64G (which translates to PAE in the processor features - or three-level page-tables if you want to use another term for it). You''ll also need to enable the same feature in Xen itself, as the Xen hypervisor and the Dom0 needs to match in page-table bitness... -- Mats> -----Original Message----- > From: xen-users-bounces@lists.xensource.com > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of > marek cervenka > Sent: 07 June 2006 15:02 > To: xen-users@lists.xensource.com > Subject: [Xen-users] xen3.0.2 4G ram > > hi, > > can you someone explain why i have only ~3GB memory available with xen > 3.0.2 (kernel 2.6.16.16) > > 2339MB HIGHMEM available. > 831MB LOWMEM available. > > --config-- > # CONFIG_NOHIGHMEM is not set > CONFIG_HIGHMEM4G=y > # CONFIG_HIGHMEM64G is not set > CONFIG_VMSPLIT_3G=y > # CONFIG_VMSPLIT_3G_OPT is not set > # CONFIG_VMSPLIT_2G is not set > # CONFIG_VMSPLIT_1G is not set > CONFIG_PAGE_OFFSET=0xC0000000 > CONFIG_HIGHMEM=y > ---cut-- > > HW Supermicro 2x xeon 4x1024 ram > > with distro kernel (rhel 2.6.9-34smp) i have full 4GB mem > > thanks > > --------------------------------------- > Marek Cervenka > ======================================> > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> -----Original Message----- > From: xen-users-bounces@lists.xensource.com > [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of > marek cervenka > Sent: 07 June 2006 16:46 > To: xen-users@lists.xensource.com > Subject: Re: [Xen-users] xen3.0.2 4G ram > > > recompiled, PAE enabled > (XEN) System RAM: 4095MB (4193308kB) > (XEN) Xen heap: 10MB (10412kB) > (XEN) Using scheduler: Simple EDF Scheduler (sedf) > (XEN) PAE enabled, limit: 16 GB > > 3200MB HIGHMEM available. > 727MB LOWMEM available.Ah, you solved it yourself!> > are there "performance" statistics for PAE vs nonPAE ?Shouldn''t be a major difference - the third level page-table only has four possible entries (one for each gigabyte), so it should "cache" pretty well. Of course handling of page-tables will be slightly more, but unlikely to be noticable in general use. -- Mats [snip] _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users