Hi All, I have discovered that setting dom0_mem also solves another problem I am facing. Previously I have complained that, after starting a HVM guest, in any pv-ops dom0 kernels 2.6.31.X, dom0 will be very slow, sluggish, and unresponsive, such that it is nearly impossible to start another HVM virtual machine. Now, after setting dom0_mem, I booted up into pvops dom0 kernel 2.6.31.5, I started all 5 Rocks HPC cluster compute nodes at one go. And guess what? Dom0 is not even sluggish! I could still do desktop screen video capturing! Voila! Setting dom0_mem is really killing two birds with one stone. It raises the number of VMs that I can start and also resolves the sluggishness in dom0 (pvops kernels 2.6.31.X affected; 2.6.30-rc3 is NOT affected) after starting a virtual machine. Setting dom0_mem really does wonders. Thank you Pasi! -- Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical Engineering) Alma Maters: (1) Singapore Polytechnic (2) National University of Singapore My Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com My Secondary Blog: http://enmingteo.wordpress.com My Youtube videos: http://www.youtube.com/user/enmingteo Email: space.time.universe@gmail.com Mobile Phone (Starhub Prepaid): +65-8369-2618 Street: Bedok Reservoir Road Country: Singapore On Mon, Nov 9, 2009 at 9:10 PM, Mr. Teo En Ming (Zhang Enming) < space.time.universe@gmail.com> wrote: > Great! After setting dom0_mem=1024M, I can start all 5 nodes of my Rocks > HPC cluster without crashing dom0 as compared to the previous limit of 3 > nodes when I did not set dom0_mem. > > Thank you Pasi! Another resource problem solved. > > Here's my latest grub.conf: > > # grub.conf generated by anaconda > # > # Note that you do not have to rerun grub after making changes to this file > # NOTICE: You have a /boot partition. This means that > # all kernel and initrd paths are relative to /boot/, eg. > # root (hd0,0) > # kernel /vmlinuz-version ro > root=/dev/mapper/vg_fedora11_host-lv_root > # initrd /initrd-version.img > #boot=/dev/sda > default=4 > timeout=100 > splashimage=(hd0,0)/grub/splash.xpm.gz > hiddenmenu > title Fedora (2.6.31.5-xen-enming.teo) > root (hd0,0) > # kernel /vmlinuz-2.6.31.5-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.31.5-xen-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.31.5-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 nomodeset > module /initrd-2.6.31.5-xen-enming.teo.img > title Fedora (2.6.31.4-xen-enming.teo) > root (hd0,0) > # kernel /vmlinuz-2.6.31.4-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.31.4-xen-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.31.4-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 nomodeset > module /initrd-2.6.31.4-xen-enming.teo.img > title Fedora (2.6.31.1-xen-enming.teo) > root (hd0,0) > # kernel /vmlinuz-2.6.31.1-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.31.1-xen-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.31.1-xen-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 nomodeset > module /initrd-2.6.31.1-xen-enming.teo.img > title Fedora (2.6.31-enming.teo) > root (hd0,0) > kernel /vmlinuz-2.6.31-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > initrd /initrd-2.6.31-enming.teo.img > title Fedora (2.6.30.5-enming.teo) > root (hd0,0) > kernel /vmlinuz-2.6.30.5-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > initrd /initrd-2.6.30.5-enming.teo.img > title Fedora (2.6.18.8-enming.teo) > root (hd0,0) > # kernel /vmlinuz-2.6.18.8-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.18.8-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.18.8-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root > module /initrd-2.6.18.8-enming.teo.img > title Fedora (2.6.31-rc6-enming.teo) with Serial Console > root (hd0,0) > # kernel /vmlinuz-2.6.31-rc6-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.31-rc6-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 iommu_inclusive_mapping=1 > com1=115200,8n1 console=com1 > # module /vmlinuz-2.6.31-rc6-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root selinux=0 xencons=ttyS0 > console=ttyS0,115200 > module /vmlinuz-2.6.31-rc6-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root selinux=0 console=hvc0 > earlyprintk=xen > module /initrd-2.6.31-rc6-enming.teo.img > title Fedora (2.6.30-rc3-enming.teo-tip) with Serial Console > root (hd0,0) > # kernel /vmlinuz-2.6.30-rc3-enming.teo-tip ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.30-rc3-enming.teo-tip.img > kernel /xen.gz dom0_mem=1024M iommu=1 iommu_inclusive_mapping=1 > com1=115200,8n1 console=com1 > # module /vmlinuz-2.6.30-rc3-enming.teo-tip ro > root=/dev/mapper/vg_fedora11_host-lv_root selinux=0 xencons=ttyS0 > console=ttyS0,115200 > module /vmlinuz-2.6.30-rc3-enming.teo-tip ro > root=/dev/mapper/vg_fedora11_host-lv_root selinux=0 console=hvc0 > earlyprintk=xen > module /initrd-2.6.30-rc3-enming.teo-tip.img > > title Fedora (2.6.31-rc6-enming.teo) > root (hd0,0) > # kernel /vmlinuz-2.6.31-rc6-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.31-rc6-enming.teo.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.31-rc6-enming.teo ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 nomodeset > module /initrd-2.6.31-rc6-enming.teo.img > title Fedora (2.6.30-rc3-enming.teo-tip) > root (hd0,0) > # kernel /vmlinuz-2.6.30-rc3-enming.teo-tip ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > # initrd /initrd-2.6.30-rc3-enming.teo-tip.img > kernel /xen.gz dom0_mem=1024M iommu=1 > module /vmlinuz-2.6.30-rc3-enming.teo-tip ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 nomodeset > module /initrd-2.6.30-rc3-enming.teo-tip.img > title Fedora (2.6.29.4-167.fc11.x86_64) > root (hd0,0) > kernel /vmlinuz-2.6.29.4-167.fc11.x86_64 ro > root=/dev/mapper/vg_fedora11_host-lv_root rhgb quiet selinux=0 > initrd /initrd-2.6.29.4-167.fc11.x86_64.img > > > -- > Mr. Teo En Ming (Zhang Enming) Dip(Mechatronics) BEng(Hons)(Mechanical > Engineering) > Alma Maters: > (1) Singapore Polytechnic > (2) National University of Singapore > My Primary Blog: http://teo-en-ming-aka-zhang-enming.blogspot.com > My Secondary Blog: http://enmingteo.wordpress.com > My Youtube videos: http://www.youtube.com/user/enmingteo > Email: space.time.universe@gmail.com > Mobile Phone (Starhub Prepaid): +65-8369-2618 > Street: Bedok Reservoir Road > Country: Singapore > > On Mon, Nov 9, 2009 at 8:18 PM, Pasi Kärkkäinen wrote: > >> On Mon, Nov 09, 2009 at 08:14:27PM +0800, Mr. Teo En Ming (Zhang Enming) >> wrote: >> > What is a good value for dom0_mem if I want to start X server and run >> > GNOME? Will 512 MB be too little? >> > >> >> Go for 1024 MB then.. >> >> -- Pasi >> >> > > > >