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SC Series array and Oracle storage management

75 Dell EMC SC Series: Oracle Best Practices | CML1114

# fdisk /dev/mapper/oraasm-data1

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to

switch off the mode (command 'c') and change display units to

sectors (command 'u').

Command (m for help): u

Changing display/entry units to sectors

Command (m for help): n

Command action

e extended

p primary partition (1-4)

Partition number (1-4): 1

First sector (61-1048575, default 61): 2048

Last sector or +size or +sizeM or +sizeK (2048-1048575, default 1048575):

Using default value 1048575

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

# partprobe /dev/mapper/oraasm-data1

# ls -ltr /dev/mapper/oraasm-data1p1

lrwxrwxrwx 1 root root 7 Apr 14 11:56 /dev/mapper/oraasm-data1p1 -> ../dm-13

For additional information on aligning disk partitions, see references in appendix B.1

6.1.5 ASM disks and Linux I/O scheduler

For optimal Oracle ASM performance, Oracle recommends the Linux I/O scheduler be set to deadline on

the devices targeted for ASM. This section assumes DM-Multipath devices, but can be applied to PowerPath

devices with little change.

To see the current I/O schedule of a DM-Multipath device, display the schedule of the corresponding device-

mapper (dm-) device:

[root]# ls -ltr /dev/mapper |grep dm-[01346]$

lrwxrwxrwx 1 root root 7 May 16 12:49 oraasm-fra1 -> ../dm-1

lrwxrwxrwx 1 root root 7 May 16 12:49 oraasm-data1 -> ../dm-0

lrwxrwxrwx 1 root root 7 May 16 12:49 oraasm-data2 -> ../dm-3

lrwxrwxrwx 1 root root 7 May 16 12:49 oraasm-crs1 -> ../dm-4

lrwxrwxrwx 1 root root 7 May 16 12:49 oraasm-fra2 -> ../dm-6

[root]# cat /sys/block/dm-[01346]/queue/scheduler

noop [deadline] cfq