oracle exadata architecture v9

8/12/2019 Oracle Exadata Architecture V9

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Architecture: Oracle Exadata vs. Teradata


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3/6/2014 Teradata Confidential Information 2

Topics

Exadata Overview> Exadata Storage Server

> HP Oracle Database Machine

Architectural Assessment

Pricing Review

Summary


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Oracle Exadata Storage Server

Specialized Storage for Oracle databases

Oracle Exadata software + HP hardware

Addresses Oracles Disk IO Bottleneck> More, small storage units

> Infiniband for higher bandwidth

> Filter rows & columns in storage server

Based on HP DL180 G5 Server> 2 Intel quad-core Xeon processors

> 8 GB RAM

> Array of 12 SAS or SATA disks 450 GB SAS disks

1TB SATA disks

> Infiniband links to Oracle DBMS> Software pre-installed Exadata software

HP Management software

Oracle Enterprise Linux

Building block of Storage server cluster> 18 Exadata servers per rack

> Multiple Racks possible


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Oracle Exadata Storage Architecture

OracleDBMS

Infiniband

ExadataSoftware

Disk array

ExadataSoftware

Disk array

ExadataSoftware

Disk array

OracleDBMS

OracleDBMS

OracleDBMS

Oracle Exadata

OracleDBMS

OracleDBMS

OracleDBMS

OracleDBMS

ArrayController

ArrayController

Oracle before Exadata

Disk array Disk arrayDisk array

Fibre Channel


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Oracle Exadata 2 layer query processing

Oracle Database layer> Aggregation

> Sort, group by

> Data redistribution

> Complex joins non-partition-wise

> Functions, UDFs, stored procs

> SQL OLAP extensions

> All other SQL processing

Exadata layer

> Projection select list columns

> Restriction where clause predicates

> Simple joins fact to dimensions

ExadataSoftware

Exadata Server

960 MBps

OracleDBMS

Software

Oracle Server

Infiniband

ExadataLayer

OracleDBMSLay

er


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HP Oracle Database Machine

Preconfigured system 8 DL360 Oracle Database servers

> 2 quad-core Intel Xeon, 32GB RAM> Oracle Enterprise Linux> Oracle RAC

14 Exadata Storage Cells (SAS orSATA)> Up to 20 TB uncompressed user data

(SAS)> Up to 46 TB uncompressed user data

(SATA)

4 InfiniBand switches 1 Gigabit Ethernet switch Growth to multiple racks


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Oracle Exadata Product Specifications

Storage Type Storage

Capacity

User Data

Volume*

Data

Bandwidth

Oracle ExadataStorage Server

450 GB SAS 5.4 TB 1-1.5 TB .96 GBps

1 TB SATA 12 TB 2.7-3.5 TB .75 GBps

HP Oracle

DatabaseMachine

450 GB SAS 75 TB 15-20 TB 13.4 GBps

1 TB SATA 168 TB 37-46 TB 10.5 GBps

* Varies from 3.5 disk to data ratio, to a more typical 4.5-5 ratio


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Architecture Assessment of Oracle Exadata

Compared to Teradata: Exadata does not put intelligence closer to the storage

Exadata is not shared nothing

Exadata does not enable high concurrency

Exadata does not support active data warehousing Exadata does not provide superior query performance

Exadata is not green

Exadata is not simple

> Trying to solve a software problem with hardware Exadata is not less expensive


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Exadata Intelligence not closer to storage

Both read data from disk intoIntel Xeon processors

Oracle divides query processingbetween Exadata & DB layers> Exadata does simple filtering

> DBMS does everything else Teradata performs all query

processing in single layer

Oracle interconnect moves dataand Interprocess Communication

Teradata BYNET only handlesIPC traffic

Teradata puts all intelligence asclose to the data as Exadataintelligent storage layer

Arraycontroller

CPUCPU

Teradata Node

2.8 GBps

375 MBps

Arraycontroller

CPUCPU

Exadata Server

960 MBps

ASM

DBMS

Oracle Server

2 GBps

RAC



Exadata not shared nothing

Exadata servers each have their own disks Each partition striped across all Exadata disks

SAME policy implemented by Oracle ASM by default

Software mirrored via ASM failure groups

Supports parallel IO across shared storage

ASM

DB

ASM

DB

Exadata Exadata Exadata

. . .

1

2

3

4

Partitions



Teradata shared nothing

Each partition on separate disks not shared

Each partition owned by separate Amp

RAID 1 hardware mirroring

TeradataTeradataTeradata

1 2 3 4 5 6 7 8 9 10 11 12

Partitions



Query processing Exadata vs. Teradata

Show total sales by store for last year

Each worker reads all Exadata disks

Yields intra-query disk contention

Each AMP reads its own disks

No intra-query disk contention

AMP1

AMP2

AMP3

AMP4

1 2 3 4

Worker1

Worker2

Worker3

Worker4


1

23

4



Exadata does not enable high concurrency

Exadata reads large blocks 4 or 8 MB

Each parallel worker reads from all Exadata disks At 80 MBps 10 concurrent IOs possible

Intra-query and inter-query contention lower throughput

Under high concurrency, DB parallel query worker processesqueue for IO

ASM

DB

ASM

DB


. . .

IO

Queue

ExadataDisk

ParallelQuery 1

ParallelQuery 2

ParallelQuery 3

ParallelQuery 4



Exadata does not support active updates

Oracle uses Multiple Version Concurrency Control (MVCC)> Ensures consistency of data in an active update environment> SCN checking (for correct data version) done in DB layer> SCN stored on data block

Exadata has two modes> Filter rows and columns and return result set> Passthrough unfiltered data blocks

Exadata returns unfiltered data blocks (passthrough)

not filtered query results.

ASM

DB

ASM

DB


. . .

12033

12035

12029

12033

12033

12035

12029

12033

12033

Select

(SCN 12033)

RollbackSegment

Scan path

Data blocks



ExadataSoftware

Exadata Server

960 MBps

OracleDBMS

Software

Oracle Server

2 GBps

Exadata Performance Simple Query

1. Query coordinator dispatches parallel Exadataquery plan

2. Each parallel slave requests exadata to readsales partitions from disk

3. Exadata filters columns & rows> Store, date, amount

> For current year

4. Exadata sends matching tuples to parallelslaves

5. Parallel slaves perform local group by and sum

6. Parallel slaves send sums by store to querycoordinator

7. Query coordinator performs global merge andreturns result set to requester

Query: Show total sales by store for YTD

1

2

3 4

5

6

7



ExadataSoftware

Exadata Server

960 MBps

OracleDBMS

Software

Oracle Server

2 GBps

Exadata Performance Complex Query

1. Query coordinator dispatches parallel Exadata queryplan

2. Each parallel slave requests exadata to read salesand customer data from disk

3. Exadata filters columns & rows

> Store, date, amount for current year> Customer demographics

4. Exadata returns matching tuples to parallel slaves

5. Parallel slaves redistribute customer data for join

6. Parallel slaves perform join

7. Parallel slaves perform local group by and sum8. Parallel slaves send sums by store to query

coordinator

9. Query coordinator performs global merge andreturns result set to requester

Query: Show sales by store by customer age, sex, income

1

2

3 4

56

7

98



Exadata Query Performance

Simple Query

ExadataSoftware

Exadata Server

960 MBps

OracleDBMS

Software

Oracle Server

2 GBps

1

2

3 4

5

6

7

ExadataSoftware

Exadata Server

960 MBps

OracleDBMS

Software

Oracle Server

2 GBps

1

2

3 4

5 6

7

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Complex Query

As Query Complexity grows

> Exadata portion gets smaller

> Benefit of Exadata lessens

> Standard Oracle DW issues

grow Exadata biggest impact

> Simpler star schemas

> Data mart applications

Exadata smallest impact

> Complex query

> Complex schema

> Mixed workload

> Ad hoc analysis



Oracle Exadata Contribution to Performance

Query Complexity

ResourceAlloca

tion(%)

25

50

75

100

Oracle DBMS

Exadata Cells

Low High



WorkloadComplexity

OPERATIONALIZINGWHAT IShappening?

ACTIVATINGMAKE it happen!

ANALYZINGWHY

did it happen?

REPORTINGWHAT

happened?

PREDICTINGWHAT WILL

happen?

Query Performance Summary

Data Sophistication

Exadata Teradata

Very good Very good

Exadata Teradata

Fair Very good

Exadata Teradata

Poor Excellent

Exadata Teradata

Poor Excellent

Exadata Teradata

Poor Excellent



Teradata vs. Oracle Exadata per rack

Teradata DWA2550

HP Oracle DBMachine

20 TB Max. User Data 15 TB

144 x 450 GB@ 15K

Active Disks168 x 450 GB

@ 15K

144 AMPs DoP Dynamic

32 Xeon64-bit @2.33 GHz

DatabaseProcessor Cores

176 Xeon (112/64)64-bit @2.66 GHz

128 GB Memory 368 (112/256) GB

Linux 64-bit OS OEL 64-bit

9.6 GB/s Peak Scan Rate 13.6 GB/s

HW RAID 1 Data Protection SW Mirroring

Oracle Exadata throwing hardware at a software problem



Exadata Pricing _ Oracles Claims

US$4000 per TBfor hardware

< US$14000 perTB for combinedhardware and

software HP Oracle

DatabaseMachine pricingof $1.68Msoftware, $650khardware.

Use your existing

database licenses



Reality: Including Oracle Database Licenses

Software List Price/CPU Subtotal

Oracle 11 Enter rise Edition 47 500 1 520 000

Real A lication Clusters $23,000 $736,000

Partitionin $11,500 $368,000

Com ression 11 500 368 000

Enterprise Manager Diagnostics

Pack

$3,500 $112,000

Enterprise Manager Tuning Pack $3,500 $112,000

TOTAL $100,500 $3,216,000

Component Price

Hardware $650,000

Exadata Software $1,680,000

Oracle RDBMS Software $3,216,000

$5,546,000

Oracleleftout

60%of the

listprice!



Oracle Database Machine vs. Teradata Family

Teradata DW Appliance less expensive than Oracle DBM w SAS disks> Fully loaded 4x advantage> Exadata only 2x advantage

Teradata Extreme DWA less expensive than Oracle DBM w SATA disks

Teradata ADW less expensive than Oracle DBM fully loaded

SpinningDisk

UserData

ExadataPrice

TotalPrice

Oracle DBM w SAS disks

(450 GB @ 15K RPM)75 TB 15 TB $2.3M $5.5M

Oracle DBM w SATA disks

(1 TB @ 7200 RPM)168 TB 37 TB $2.3M $5.5M

Teradata ADW

(300 GB @ 15K RPM)44 TB 28 TB -- $4.2M

Teradata DW Appliance

(450 GB @ 15K RPM)43 TB 20 TB -- $1.3M

Teradata Extreme DWAppliance (1 TB @ 7200 RPM) 124 TB 50 TB -- $0.8M



Oracle Database Machine vs. Teradata Family

Teradata DW Appliance> less expensive than Oracle DBM fully loaded (SAS or SATA)> Less expensive than Oracle DBM w SAS (Exadata only)

Teradata ADW less expensive than Oracle DBM w SAS (fully loaded)

Teradata Extreme DW Appliance cheaper than Oracle w SATA

TeradataADW

TeradataDW

Appliance

TeradataExtreme

DWAppliance

OracleDBM

w SATA

OracleDBM

w SAS

$100K

$200K

$300K

$400K

Exadata onlyOracle DBMS

Teradata DBMS

$150K

$65K

$16.5K

$150K

$370K

$155K

$63KPriceper

TBofUserData



Summary

Oracle Data Base Machine :> Is not ground breaking

> Is not cheap

> Is not an appliance - still multiple support points

> Is not an EDW solution EDW requires more than fastscans

> Does not solve most of Oracle's DW performance problems

> HP Oracle DMB is not a balanced system

> Is unnecessarily complex

So what does it do?> Address a Oracle configuration problem

> Emphasize the OOWI reference arch



Thank You!



TeradataDBMS

Software

Teradata Node

2.8 GBps

375 MBps

Teradata Performance Simple Query

1. PE dispatches parallel query plan to AMPs

2. Each AMP to read partition data from disk

3. AMPs filter columns & rows

> Store, date, amount

> For current year

4. AMPs perform local group by and sum

5. AMPs redist local groups for global merge

6. AMPs perform global merge and returns result

set to PE7. PE returns result set to requester

Query: Show total sales by store for YTD

1

2

3

4

5

6

7


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TeradataDBMS

Software

Teradata Node

2.8 GBps

375 MBps

Teradata Performance Complex Query

1. PE dispatches parallel query plan to AMPs

2. Each AMP reads sales and customer data fromdisk

3. AMPs filters columns & rows

> Store, date, amount for current year> Customer demographics

4. AMPs redistribute customer data for join

5. AMPs perform join

6. AMPs perform local group by and sum

7. AMPs redist local groups for global merge8. AMPs perform global merge and returns result

set to PE

9. PE returns result set to requester

Query: Show sales by store by customer age, sex, income

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2

3

4

5

6

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oracle exadata architecture v9

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