UbuntuRAID0ssd

Ubuntu RAID0 SSD no root w/o boot partition

During install

Jump over to another tty

# apt-get -y install lvm2

Make sure partition starts on 2048

# fdisk -l

Disk /dev/sda: 32.0 GB, 32017047552 bytes
132 heads, 63 sectors/track, 7519 cylinders, total 62533296 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000a5046

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048    62533295    31265624   8e  Linux LVM

Disk /dev/sdb: 32.0 GB, 32017047552 bytes
132 heads, 63 sectors/track, 7519 cylinders, total 62533296 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xd67db81c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048    62533295    31265624   8e  Linux LVM

Create PV's with aligned metadata

# pvcreate --metadatasize 250k /dev/sda1
# pvcreate --metadatasize 250k /dev/sdb1

Create VG and LV

# vgcreate  vgssd /dev/sda1 /dev/sdb1
# vgdisplay vgssd | grep Total
  Total PE              15266
# lvcreate -i2 -I128 -n lvssd vgssd --extents 15266

Create file system

# mkfs.ext4 -v -O ^has_journal -m 0.1 -E stride=32,stripe-width=64 /dev/vgssd/lvssd
# tune2fs -c 0 /dev/vgssd/lvssd

Post Install Before Reboot

Add bits for lvm and nfs on next boot

# mount -o bind /dev /target/dev
# mount -o bind /sys /target/sys
# mount -o bind /proc /target/proc
# chroot /target
# sudo apt-get -y install lvm2 nfs-common

/etc/fstab modifications

UUID="6239bc41-8816-47b6-b7d5-2be592f8b69b" /               ext4    noatime,discard,errors=remount-ro 0 1

# Keep excessive writes in /tmp, and I use a remote syslog server
none		/tmp		tmpfs	size=300M	0 0
none		/var/log	tmpfs	defaults	0 0

# Mount network raid array and lets keep apt cache over there via bind mount
192.168.1.20:/mnt/raid5 /mnt/raid5	nfs	defaults	0 0
/mnt/raid5/drew/drew-desktop/archives/ /var/cache/apt/archives/	nfs	bind 0 0

/etc/rc.local additions

echo deadline >/sys/block/sdg/queue/scheduler
echo deadline >/sys/block/sdh/queue/scheduler
find /sys/devices -name nr_requests -exec sh -c 'echo 4096 > {}' \;

/etc/sysctl.conf additions for swap

vm.swappiness to 1

Update grub2

• Note may require rebuild of initial ram disk -

# mv /boot/initrd.img-3.2.0-20-generic initrd.img-3.2.0-20-generic.old
# mkinitramfs -o /boot/initrd.img-3.2.0-20-generic
# update-grub
# grub-install /dev/sda
# grub-install /dev/sdb

Reboot from Installer

Once in OS lets stop a few things from wearing out the SSD's.

Move Firefox cache off ssd

• firefox-> about:config -> new string -> browser.cache.disk.parent_directory to /tmp/drewff

Sources

• https://sites.google.com/site/lightrush/random-1/checkiftrimonext4isenabledandworking
• http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/newmds-ssdtuning.html
• http://www.ocztechnologyforum.com/forum/showthread.php?82648-software-RAID-LVM-TRIM-support-on-Linuxking
• http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/newmds-ssdtuning.html
• https://wiki.archlinux.org/index.php/Solid_State_Drives#Mount_Flags