Oracle ASM Reduces Cost of VLDB Deployment Hanan Hit, Principal Database Architect Lina Shabelsky, Senior Application and Database Engineer NOCOUG Winter Conference February 08, 2007

Confidential and Proprietary Agenda Application description What ASM is and is not Protocol etc. Deployment models Network design Physical architecture Oracle operations to reduce required I/O Index creation stats Best practices Lessons learned during VLDB implementation Backup and recovery

Application Description

Confidential and Proprietary Logical Database Structure Management Db Operational Data Store Historical Data Store Archive Data Store (SATA) OLAP

Confidential and Proprietary General Loading Schema Staging ODS – Last Hour Data Warehouse OLAP Bus Loader Aggregators

Confidential and Proprietary High Level – Physical Layer

What ASM is and is not

Confidential and Proprietary ASM - Flexible, Efficient, Time Saver Vertically integrated file system Easy file management system Management of: -Raw device volume -Oracle data files -Online and archive logs -RMAN backup Multi platform availability Stripes data across all raw volumes Hot spot detection and correction Optional mirroring (best with SAN/NAS) but striping is NOT Oracle 10g Release 1 and above

Confidential and Proprietary What ASM is NOT A cluster file system Available for non Oracle files Available for OCR and voting disks General file system

Confidential and Proprietary Options prior to ASM Raw With LVM Without LVM Cooked With LVM Without LVM

Confidential and Proprietary Why We Chose ASM in the First Place? New implementation using 10g Linux RHEL shop Mid range storage array - full enterprise business needs “Just trust the hardware to handle it”  Not a workable solution (DBA’s) Expected thousands of data files  Didn’t want to use the BIG File option (YET). RAC & non RAC implementations Obvious need for storage growth with unpredictable limit size Do more with less  Very few DBAs & sys/storage admin Block level access to storage Easy storage provisioning

Protocol

Confidential and Proprietary Which Protocol to Use? FC – SAN (2/4 GBit/s) iSCSI – IP-SAN (2/4 GBit/s) NFS – NAS (2/4 GBit/s) FCIP

Confidential and Proprietary What is iSCSI Protocol? A network protocol standard that allows the use of the SCSI protocol over TCP/IP networksnetwork protocol SCSITCP/IPnetworks A transport layer protocol in the SCSI-3 specifications frameworkSCSI Expected to capture more than 10% of storage systems revenue and an even greater percentage of capacity by Hot technologies for 2007 (Storage Magazine) “iSCSI SAN is definitely happening” - Stephen Foskett, GlassHouse Technologies Inc., Framingham, MA

Confidential and Proprietary Wikipedia iSCSI Definitions iSCSI initiator in client/server terminology, is akin to a client device that connects to some service offered by the server (in this case an iSCSI target). An iSCSI target is akin to a server, in that it provides block level access to its storage media (usually a hard drive, but can be other types of SCSI devices). Only one iSCSI initiator can talk to a given iSCSI target at a time (one-to-one).

Confidential and Proprietary Simple iSCSI system

Deployment Models

Confidential and Proprietary Deployment Models Separate Disk Groups  Use storage base features for ASM deployment data management  Backup/recovery, cloning etc. Shared Disk Groups  Use Oracle tools exclusively for all data management methods

Confidential and Proprietary Separate Disk Groups

Confidential and Proprietary Shared Disk Groups

Confidential and Proprietary Shared Disk Group- Multiple RAC Instances

Network Design

Confidential and Proprietary Typical Performance in MB/s System ComponentThroughput /Performance BitsBytes 16 Port Switch8 *2GBit/s1200 MB/s Fibre Channel2 GBit/s200 MB/s Disk Controller 2 GBit/s180 MB/s GigE NIC2 GBit/s80 MB/s 1 Gbit HBA1 GBit/s100 MB/s 2 Gbit HBA2 GBit/s200 MB/s

Confidential and Proprietary iSCSI End Point Options

Confidential and Proprietary Network Configuration

Physical Architecture

Confidential and Proprietary FAS3050 #1

Confidential and Proprietary FAS3050 #2

Confidential and Proprietary FAS3020

Confidential and Proprietary Database size

Oracle operations to reduce required I/O

Confidential and Proprietary Oracle Operations - Reduce Disk I/O Index creation on many billions of rows  New software version while supporting legacy data Gathering Oracle stats

Index creation statistics

Confidential and Proprietary Index Creation – New App Version Set/unset the SKIP_UNUSABLE_INDEXES  When set to TRUE Oracle will not attempt to use or report errors when an index is marked as unusable System Level - ALTER SYSTEM SET SKIP_UNUSABLE_INDEXES = TRUE; Session Level ALTER SESSION SET SKIP_UNUSABLE_INDEXES = TRUE;

Confidential and Proprietary Index Creation – New App Version Step 1 - Create the new index with the UNUSABLE attribute Step 2 - System Level - ALTER SYSTEM SET SKIP_UNUSABLE_INDEXES = TRUE; Step 3 - ALTER INDEX MODIFY PARTITION UNUSABLE;  On all partitions. If using a Global Index then mark the entire index as UNUSABLE Step 4 - ALTER INDEX REBUILD PARTITION NOLOGGING;  On the most fresh partition this will enable the application to run with the new index ASAP. Step 5 - ALTER INDEX REBUILD PARTITION NOLOGGING;  On all the legacy (non hotspot) partitions. This will be rebuild according the system workload. Final Step - System Level - ALTER SYSTEM SET SKIP_UNUSABLE_INDEXES = FALSE;

Confidential and Proprietary Gathering Oracle Stats Gather partitions statistics (First time)  Exec dbms_stats.gather_table_stats(ownname=>‘ ', tabname => ‘ ', PARTNAME=> ‘ ', estimate_percent => DBMS_STATS.AUTO_SAMPLE_SIZE, cascade=>TRUE, method_opt=>'FOR ALL COLUMNS SIZE AUTO');  Exec dbms_stats.gather_table_stats (ownname=>‘ ', tabname=>‘ ', PARTNAME=> ' ', estimate_percent=>1,CASCADE=> true); Unlock Statistics (If previously locked)  Exec dbms_stats.unlock_table_stats(OWNNAME=>‘ ', TABNAME=>‘ ');

Confidential and Proprietary Gathering Oracle Stats – More Copy statistics  Execdbms_stats.COPY_TABLE_STATS(OWNNAME=>‘ ', TABNAME=>‘ ', SRCPARTNAME=>‘ ', DSTPARTNAME=>' '); Lock table statistics  Exec dbms_stats.lock_table_stats(OWNNAME=>‘ ', TABNAME=>‘ ');

Confidential and Proprietary Index Creation Example

Confidential and Proprietary Index Creation Example – More

Best Practices

Confidential and Proprietary NetApp/ASM – Our Best Practices Single aggregate FlexVol ASM external redundancy Separate disk groups Maximum volume size allowed 16TB while recommended is not more then 3TB Use RAID-DP with maximum 16 drives in a single RAID group Set minra to off – even on DSS Jumbo frames – 9K MTU Single mode VIF

Lessons learned during VLDB implementation

Confidential and Proprietary RAC 10gR2 Implementation Learnings Implementation of VLDB in RHEL 4.3, software iSCSI, NetApp and ASM environment Procedure of provisioning additional storage Backup procedures with NetApp SnapManager for Oracle

Confidential and Proprietary Network Implementation Isolate your database from the rest of the IP traffic Use separate VLAN for access to the storage Use oifcfg to verify the setup of your interfaces Use IP bonding on both – server and filer to achieve network stability and as an alternative solution to multipathing IP bonding allows you to aggregate multiple network interfaces into higher performance network link and provides failover solution

Confidential and Proprietary Oracle Clusterware Carefully plan your file system layout If you use ASMLIB with iSCSI disks, don’t map OCR and voting disk to raw devices in RAC environment – use OCFS or NFS Raw devices are not aware of ASMLIB In RedHat 4 update 3, the use of /etc/sysconfig/rawdevices is deprecated

Confidential and Proprietary Storage When planning for the large database consult your storage vendor about RAID configuration, storage provisioning and backup procedures. As an example – using NetApp as storage appliance allows DBAs to take advantage of RAID-DP (Double Parity) – fault tolerance of RAID 1 at the price of RAID 4. NetApp flexible architecture allows DBAs to provision additional storage with minimal downtime. SnapManager for Oracle allows DBAs to combine NetApp snapshot technology with Oracle RMAN to dramatically decrease time taken to backup and restore database.

Confidential and Proprietary Storage Provisioning with ASM Adding 1TB of storage takes no more than 30 minutes with Netapp Step1 – Ask your system administrator to plug in Netapp shelves Step 2 – login to the filer and add new disks to the aggregate leaving 2 spares per array Step 3 – create new volume and LUNs, add them to the initiator group

Confidential and Proprietary Filer view

Confidential and Proprietary Adding Storage to the Database Step 4 - After new LUNs created on the filer, reboot the database server to automatically discover new LUNS. You can verify that LUNs are accessible from the database server using NetApp host utilities:

Confidential and Proprietary Creating ASM Disks Step 5 – run fdisk on new devices. Step 6 – run /etc/init.d/oracleasm createdisk. Last step – connect to ASM instance and execute “create diskgroup…” command. You can also use Enterprise Manager db control :

Backup and Recovery

Confidential and Proprietary SnapManager for Oracle Backups A management tool with a GUI and command-line interface for Oracle Database administrators that simplifies backup, recovery, and cloning for Oracle Databases Designed to leverage Oracle Database 10g data management and grid features such as ASM, RAC, and RMAN Utilizes NetApp Snapshot technology to create extremely fast and space-efficient backups  Snapshot copies are point-in-time copies of a database that are created nearly instantaneously.  These backups can also be registered with Oracle RMAN, which facilitates the use of RMAN to restore and recover the database at finer granularities such as blocks.

Confidential and Proprietary How SnapManager Works To create a successful backup, SnapManager performs the following operations:  Determines the list of data files, control files, and log files that make up the database. These files can be located on one or more ASM disk groups.  Puts the database in hot backup mode  Creates an atomic Snapshot copy of all the filer volumes that make up the ASM disk group  Ends the hot backup mode  Clones the Snapshot copy and then renames the cloned ASM disk group  Verifies the backup  Registers the cloned ASM disk group and storage information in the RMAN repository

Confidential and Proprietary Disk Backup vs. SnapManager Backup To demonstrate the benefit of snapshot backup technology we measured the time taken to backup 70GB database to the disk. Here’s what we found: Backup to the disk: Backup set complete, elapsed time: 00:25:20 It would take about 18 hours to backup 3 TB database.

Confidential and Proprietary Time Log for SnapManager Backup :43:45,396 [INFO ]: SMO-07100: Placing database into online backup mode :46:00,724 [DEBUG]: SMO-12000: Executing SnapDriveCommand :46:04,762 [DEBUG]:SMO-12001: Result SnapDriveResult (0:00:04.037) (took 4 seconds to take a snapshot of the volume) :55:55,841 [INFO ]: SMO-13037: Successfully completed operation: Backup :55:55,947 [INFO ]: SMO-13048: Operation Status: SUCCESS :55:56,030 [INFO ]: SMO-13049: Elapsed Time: 0:12: (including all backup management procedures) From database alter log: Fri Nov 10 17:43: ALTER DATABASE BEGIN BACKUP Fri Nov 10 17:46: ALTER DATABASE END BACKUP

Confidential and Proprietary Restore Operation Similar to backups, SnapManager for Oracle relieves the DBA from having to worry about the underlying layout of data in terms of storage subsystems, disks, host volumes, or host file systems. DBAs just choose the backup they want to restore from, and SnapManager does the rest. DBAs can also specify the date and time or the Database SCN to which they would like the database restored.

Thank you Hanan Hit, Principal Database Architect Lina Shabelsky, Senior Application and Database Engineer