Sungju's Slow Life

Personal journal


  • How to improve the nova storage performance

    If you are using KVM for virtualisation in OpenStack, you might notice some big slowness with the virtual storage. You can improve the performance by using the hypervisor’s volume group directly. You just need to create a volume group and specify that in /etc/nova/nova.conf. libvirt_images_type=lvm libvirt_images_volume_group= Continue reading

  • How to check LVM usage history

    If your lvm storage has some problem, you can dump it with the following command. $ dd if= of=lvm_head.out bs=100M count=1 $ strings lvm_head.out > dump.txt And make the following awk script (lvm_history.awk) to check the history. BEGIN { new = 1 pecount = 0 } { if ($1 == “pe_count”) pecount = $3 if… Continue reading

  • LVM filter generation

    To limit unnecessary I/O, you might need to make a filter in /etc/lvm/lvm.conf and sometimes, it’s hard to find a proper filter configuration. Here is a simple way you can get a good filter. $ pvs -a –config ‘devices { filter = [ “a|.*|” ] }’ –noheadings -opv_name,fmt,vg_name | awk ‘BEGIN { f = “”;… Continue reading

About Me

A software engineer who loves any technologies that makes life easier. That’s why I love Linux and Mac at the same time.