Automatic Storage Management

1
Automatic Storage Management
2
Storage Management Gap
Avg. Managed Capacity per Administrator In
Database Sites with gt100 GB Capacity
3
DBA Storage Challenges

• Databases are rapidly growing in size
• DBAs have to manage thousands of data files
• Decreasing windows of scheduled downtime
• Storage resources involve many organizations
• Database Admin
• Systems Admin
• Storage Admin
• Network Admin
• Management of database storage is increasing in
  complexity and cost

4
Automatic Storage Management

• Provides a vertical integration of the file
  system and volume manager for Oracle database
  files
• Spreads database files across all available
  storage for optimal performance and resource
  utilization
• Enables simple and non-intrusive resource
  allocation and provides automatic rebalancing

5
The Operational Stack
ASM
TODAY
Tables
Tables
Tablespace
ASM
Tablespace
Files
Files
File System
File System
Logical Vols
Logical Vols
Disks
Disk Group
The best way to lower mgmt costs is to remove
complexity
6
ASM Disk Groups

• A pool of disks managed as a logical unit

Disk Group
7
ASM Disk Groups

• A pool of disks managed as a logical unit
• Partitions total disk space into uniform sized
  megabyte units

Disk Group
8
ASM Disk Groups

• A pool of disks managed as a logical unit
• Partitions total disk space into uniform sized
  megabyte units
• ASM spreads each file evenly across all disks in
  a disk group

Disk Group
9
ASM Disk Groups

• A pool of disks managed as a logical unit
• Partitions total disk space into uniform sized
  megabyte units
• ASM spreads each file evenly across all disks in
  a disk group
• Coarse or fine grain striping based on file type

Disk Group
10
ASM Disk Groups

• A pool of disks managed as a logical unit
• Partitions total disk space into uniform sized
  megabyte units
• ASM spreads each file evenly across all disks in
  a disk group
• Coarse or fine grain striping based on file type
• Disk groups integrated with Oracle Managed Files

Disk Group
11
ASM Disk Groups

• Administer disk groups not files
• Number of disk groups remains constant while
  number of files and disks continually increases

Fast Disk Group
Slow Disk Group
12
Mirroring with ASMFailure Groups

• Storage resources organized into Disk Groups and
  Failure Groups
• A Disk Group is a collection of disks managed as
  a logical unit in which ASM files are stored
• Disk Groups assigned by DBAs
• A Failure Group is a set of disks sharing a
  common resource whose failure needs to be
  tolerated
• Redundant copies of an extent are stored in
  separate Failure Groups
• Failure Groups assigned by DBAs or automatically
  by ASM

Disk Group 1
13
Mirroring with ASM

• 3 choices for disk group redundancy
• External defers to hardware mirroring
• Normal 2-way mirroring
• High 3-way mirroring

14
ASM Mirroring

• Mirror at extent level
• Mix primary mirror extents on each disk

15
ASM Mirroring

• Mirror at extent level
• Mix primary mirror extents on each disk

16
ASM Mirroring

• No hot spare disk required
• Just spare capacity
• Failed disk load spread among survivors
• Maintains balanced I/O load

17
Where DBAs Spend Their Time
Installation 6
Others 15
DataLoading 6
Ongoing System Management 55
Source IOUG 2001 DBA Survey
18
ASM FunctionsDrill Down

• Getting started
• Defining a DB
• Adding/deleting/migrating storage
• Hot spots
• Storage fragmentation

19
Traditional vs ASMSetup

• Determine required storage capacity
• Install Volume Manager, File System
• Architect data layout to avoid hot spot
• Create logical volumes
• Create file systems
• Install database
• Create database

• Determine required storage capacity
• Install ASM
• Create Disk Groups
• Install database
• Create database

20
Create or Delete Disk Groups
CREATE DISKGROUP dgroup1 DISK /dev/raw/raw
CREATE DISKGROUP dgroupA NORMAL REDUNDANCY
FAILGROUP controller1 DISK '/devices/diskA1'
NAME diskA1 SIZE 120G, '/devices/diskA2',
'/devices/diskA3' FAILGROUP controller2 DISK
'/devices/diskB1', '/devices/diskB2',
'/devices/diskB3'
DROP DISKGROUP dgroupA INCLUDING CONTENTS
21
Traditional vs ASMAdd Disk

• Add Disk to OS
• Create volume(s) with Volume Manager
• Create File System over volume
• Figure out data to move to new disk
• Move data to new files
• Rename files in database
• Re-tune I/O

• Add Disk to OS
• Issue the Add Disk command

22
Adding Disks to Disk Groups
ALTER DISKGROUP dgroupA ADD DISK
'/dev/rdsk/c0t4d0s2'
Disk Added to Disk Group
Disk Group Rebalancing
23
Traditional vs ASMRemove Disk

• List all data that is on disk
• Choose existing filesystem to hold data from
  dropped disk
• Move data to new files
• Rename files in database
• Remove disk from OS
• Re-tune I/O

• Issue drop disk command
• Remove the disk from OS when Oracle says it is
  done

24
Removing Disks to Disk Groups
ALTER DISKGROUP dgroupA DROP DISK Group2_0003
Disk Group Rebalancing
ALTER DISKGROUP dgroupA REBALANCE POWER 5
25
DEMO
26
Traditional vs ASMMigrate Data

• Add new disks to OS
• Figure out new location on other disks
• Create volume(s) with Volume Manager
• Create new FS
• Move data to new files
• Rename files in database
• Remove old disks from OS
• Re-tune I/O

• Add new disks to OS
• Issue Add disk command for new disks
• Issue Drop Disk command for old disks
• Remove old disks from OS when Oracle says it is
  done

27
Traditional vs ASMTune I/O

• Daily monitor I/O performance
• Discover hot spots
• Figure out how to remove hot spots
• Move data to new files
• Rename files in database
• Verify that hot spot is gone

• This space intentionally left blank

28
Traditional vs ASMManage Space

• Daily monitor storage utilization
• Discover fragmentation
• Figure out how to remove fragmentation
• Move data to new files
• Rename files in database
• Verify that fragmentation is gone

• This space intentionally left blank

29
ASM Lowers Management Costs
8
7
7
6
6
6
5
4
2
2
0
0
Best way to save costs is to remove complexity
30
Integration with Oracle toolsAKA How do we get
data out?

• Backup
• Rman
• Transportable Tablespaces
• ftp to FTP server
• Data Pump
• Can specify disk group and data pump will dump to
  ASM

31
Why We Stripe

• Automatic Storage Management Extends SAME
• Allows dynamic and online reconfiguration of
  storage resources
• Efficient relocation of data during rebalance
• Eliminate manual I/O tuning in all storage
  configurations

32
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes

Disk Group
33
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Only move data proportional to storage added

Disk Group
34
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Only move data proportional to storage added
• No need for manual I/O tuning

Disk Group
35
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Online migration to new storage

Disk Group
36
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Online migration to new storage

Disk Group
37
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Online migration to new storage

Disk Group
38
Dynamic Rebalancing

• Automatic online rebalance whenever storage
  configuration changes
• Online migration to new storage

Disk Group
39
ASM Architecture
ASM Instance
NonRAC Database
Oracle DB Instance
Server
Pool of Storage
Disk Group
40
ASM Instance

• Lightweight instance
• Few processes
• No database to mount, metadata tripled mirrored
  in ASM diskgroup
• Initialization Parameters

INSTANCE_TYPE OSM OSM_POWER_LIMIT
11 OSM_DISKSTRING '/dev/rdsk/s2',
'/dev/rdsk/c1' OSM_DISKGROUPS dgroupA,
dgroupB LARGE_POOL_SIZE 8MB
41
Database and ASM Instance Interaction
42
ASM Architecture
ASM Instance
NonRAC Database
Oracle DB Instance
Server
Pool of Storage
Disk Group
43
ASM Architecture
ASM Instance
ASM Instance
Oracle DB Instance
Oracle DB Instance
RAC Database
Clustered Servers
Clustered Pool of Storage
Disk Group
44
ASM Architecture
ASM Instance
ASM Instance
Oracle DB Instance
Oracle DB Instance
RAC Database
Clustered Servers
Clustered Pool of Storage
Disk Group
Disk Group
45
ASM ArchitectureEnables Consolidated Clustered
Storage
ASM Instance
ASM Instance
ASM Instance
ASM Instance
RAC or NonRAC Databases
Oracle DB Instance
Oracle DB Instance
Oracle DB Instance
Oracle DB Instance
Oracle DB Instance
Clustered Servers
Clustered Pool of Storage
46
Migration of File System Tablespace to ASM
RMANgt BACKUP AS COPY TABLESPACE USERS FORMAT
DGROUPA
RMANgt SWITCH TABLEPSACE USERS TO COPY
47
Summary

• New capability in Oracle 10g Database
• Provides a vertical integration of the file
  system and volume manager for Oracle database
  files
• Spreads database files across all available
  storage for optimal performance and resource
  utilization
• Enables simple and non-intrusive resource
  allocation and provides automatic rebalancing

48
ASM Benefits

• Increases the productivity of the DBA
• Simplified management interface for storage
  resources
• Eliminates manual I/O performance tuning tasks
• Virtualizes the storage to a set of disk groups
• Provides mainframe class performance at lower cost

49
(No Transcript)
50
ASM is NOT!

• Not a general purpose FS or CFS
• Not using any special I/O calls below the OS
• Not a tool designed for SA or Storage Admins
• Not vendor or platform specific
• Not the only tool needed to provision storage
• Not required do the mirroring
• Not used for binaries, trace and text files
• NOT RAW