A DAPT IST-2001-37126 Composite Services Gustavo Alonso Swiss Federal Institute of Technology (ETHZ) Zürich, Switzerland

ADAPT IST-2001-37126

Composite Services

Gustavo Alonso

Swiss Federal Institute of Technology (ETHZ)

Zürich, Switzerland

ADAPTADAPT IST-2001-37126

Outline

• Our vision and grand goals

• State of the art and influence on ADAPT

• Progress so far

• Work on year two


Our vision

Automating the integration of IT infrastructures through Web service composition, business protocols, and conversation

specifications

Servicespecification

Automatic extraction of service data

Automatedsupport for composition

Automated validation of the compositionEnactment


Our grand goals

• Through automation and leveraging Web services we hope to:– reduce the development cost of B2B applications– make Web service technology available to SMEs– create the basics for plug&play Web service technology– complement standardization in areas that are currently not

being well covered by industry efforts– hide the complexity and changing nature of Web service

technology from the end user – contribute to standardization efforts in composite services– open source platform


State of the art

• Many important developments in the last year:– BPEL specification– BPEL implementations (Collaxa, BPELWS4j)– Many additional specifications relevant to composition (WS-

CAF, WSIF, WS-Coordination, WS-Transactions, Grid, etc.)

• Many changes and not a clear direction

• Competing standards without a clear winner (ebXML, xCBL)

• Luckily, this situation does not negatively influence our plans within ADAPT (so far, we will keep a close watch)– our goals still beyond the scope of industry efforts– we profit from all the tools that have become available


Influences on ADAPT

CONCEPTUAL DESIGN

• Use of Web service specifications is ill defined and changing

• The range of design options is widening and may require us to focus on a particular application type

• The focus is also shifting in industry (from simple services to conversations)

ACTUAL ARCHITECTURE

• Increasing number of tools available (to enhance the work on ADAPT, or to give us a link to products)

• May have to postpone some design decisions until a later stage than planned

• Otherwise, the initial goals of the ADAPT platform for composition remain unchanged


Progress so far

• Two prototype composition engines (based on previous work) capable of automatically importing information about Web services (WSDL description), embedding the operations within a workflow process, and invoking the services using SOAP– Centralized engine (Java)– Distributed engine (Java)– Bottom up composition

• Graphical tool for composition

• Consensus formed on model behind composition (Pi calculus) and properties of composition that we will support (transactions, choreography).


Evaluation of progress so far

• All the background work has been done:– thorough understanding of available technology– flexible design to keep our options open (centralized,

distributed, bottom up composition, top down composition, conversation based composition, etc.)

• Existing prototypes provide excellent platform for experimentation and exploring interaction of heterogeneous systems

• Consensus emerging on what are the limits to what we can do in ADAPT, what we can take from others (e.g., TAPAS), and where the strength of the open source platform will be


Planned work for year two

• Consolidation of the prototypes– possible decision to go with only one engine (not necessary)

• Closer look at top down composition (as an extension or alternative)

• Tying together of graphical tool, engines and composition model in a single unified framework– careful attention to standards (BPEL)

• Work on adaptive composition and automated analysis– transactions– choreography and business protocols

• First version of the ADAPT platform

ADAPT IST-2001-37126

http://www.iks.ethz.ch/jopera


JOpera Architecture

Kernel

Navigator DispatcherProcessTemplate

Plugin

ProcessTemplate

PluginU

NIX

SO

AP

JAV

A

....

StateInformation

Storage

Event Queues

TaskExecutionScheduler


JOpera Distributed Kernel

Navigator

Navigator

Dispatcher

Dispatcher

Dispatcher

ProcessTemplate

Plugin

ProcessTemplate

Plugin

ProcessTemplate

Plugin

ProcessTemplate

PluginU

NIX

UN

IXU

NIX

SO

AP

SO

AP

SO

AP

JAV

AJA

VA

JAV

A

........

....

StateInformation

Storage

Event QueuesTask

ExecutionScheduler

Kernel


JOpera Storage Architecture

State InformationStorageLocalMain

Memory

State InformationStorage

RemoteTupleSpace

State InformationStorage

Main MemoryWrite-through

Cache

RemoteTupleSpace


Cost of persistent storage

0

50

100

150

200

250

300

350

400

1 64 128 256 512 1024

Number of concurrent processes

Ave

rag

eW

all

Tim

e(s

eco

nd

s)

Volatile

Storage Configuration:

Process Size: tasksControl Flow:

10Parallel

Persistent (with Cache)

Persistent

0

100

200

300

400

500

600

700

1 64 128 256 512 1024


Ave

rag

eW

all

Tim

e(s

eco

nd

s)

Volatile

Storage Configuration:


10Sequential

Persistent (with Cache)

Persistent

0

500

1000

1500

2000

1 64 128 256 512 1024


Ave

rag

eW

all

Tim

e(s

eco

nd

s)

0

1000

2000

3000

4000

5000

1 64 128 256 512 1024


Ave

rag

eW

all

Tim

e(s

eco

nd

s)

VolatileVolatile

Storage Configuration:Storage Configuration:


100Matrix


100Parallel

Persistent (with Cache)Persistent (with Cache)

PersistentPersistent


Process instantiation time

0.1

1

10

100

1000

0 5 10 15 20 25

Number of Navigators

Pro

cess

inst

anti

atio

nti

me

(mil

lise

con

ds)

State Information Storage

Centralized, Persistent

Distributed, Volatile

Process Size1 task10 tasks100 tasks


Throughput degradationThroughput of a monolythic kernel

0 5 10 15 20 25 30

Matrix(100)

Parallel(100)

Parallel (10)

Sequential(10)

Sequential(1)

Pro

cessto

po

log

yan

dsize

Throughput (tasks/sec)

64

128

256

512

1024

Number ofconcurrentprocesses


Scalability (Response time)Distributed Tuple Space - Sequential (1 sec)

10

100

1000

10000

0 5 10 15 20 25

641

1

164

64

64

128

128

128

128

256

256

256

256

512

512

512

512

1024

1024

2048

10242048

1024

2048

2048


BB

aa

tt

cc

hh

EE

xx

ee

cc

uu

tt

ii

oo

nn

TT

ii

mm

ee

((

ss

ee

cc

oo

nn

dd

ss

))

Distributed Tuple Space - Sequential (10 sec)

10

100

1000

10000

0 5 10 15 20 25


Bat

chE

xecu

tio

nT

ime

(sec

on

ds)

Tuple Space (Local) - Sequential (1 sec)

10

100

1000

10000

0 5 10 15 20 25


Tuple Space (Local) - Sequential (10 sec)

10

100

1000

10000

Configuration: storageTask duration: seconds

Persistent10

Configuration: storageTask duration: second

Persistent1

Configuration: storageTask duration: seconds

Volatile10

Configuration: storageTask duration: second

Volatile1

0 5 10 15 20 25


Bat

chE

xecu

tio

nT

ime

(sec

on

ds)

1


Scalability (throughput)

1o Parallel tasks - Persistent storage

1o Parallel tasks - Volatile storage

0

20

40

60

80

100

120

140

160

0 5 10 15 20 25Number of Navigators

Th

rou

gh

pu

t(t

asks

/sec

on

d)


6412825651210242048

0

50

100

150

200

250

300

350

400

0 5 10 15 20 25Number of Navigators

Th

rou

gh

pu

t(t

asks

/sec

on

d)


6412825651210242048


Split/Merge Options


Reliable WS Call

Static

Dynamic

output

input

SYS.progService

ServiceCall,ServiceCall_Alternate,ServiceCall_Backup,ServiceCall_Backup2

serviceNames

matchName

getServiceList

ServiceCall*

output

input

SYS.progService


Visual XML Transformation<Adresse>

<name> </name><nachname> </nachname><strasse> </strasse><plz> </plz><ort> </ort><kanton> </kanton>

</Adresse>

CesarePautassoHirschengraben 84

8072Zurich

ZH

<Address><name> </name><street> </street><number> </number><town> </town><state> </state>

<country> </country></Address>

Cesare PautassoHirschengraben84

ZurichZH

Switzerland<zip> </zip>8072

name street number ziptown state country

pack_Address

name nachname strasse plz ort kanton

unpack_Adresse

ab

a b

Concatenate

s n

a

Split Switzerland


WS Demo Process

symbol country

StockQuoteConvert Input

quote

StockQuoteConvert Output

symbol

Result

Quote

country1country2

Result

Convert

usa

a b

result

Multiply

StockQuoteConvert - DataFlow

This process is included as an example of WS composition with the current JOpera release

Documents

A DAPT IST-2001-37126 Composite Services Gustavo Alonso Swiss Federal Institute of Technology (ETHZ) Zürich, Switzerland