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Active Demux (10 Methods) (10 Demux Active
Active Demux (100 Methods) (100 Demux Active Number of Objects of Number GPERF (1 Method) (1 GPERF
GPERF (10 Methods) (10 GPERF Dynamic Hash (10 Methods) (10 Hash Dynamic Dynamic Hash (1 Method) (1 Hash Dynamic
GPERF (100 Methods) (100 GPERF Dynamic Hash (100 Methods) (100 Hash Dynamic
1
dynamic 100 200
300
400 500
is but compatible, Linear (10 methods) (10 Linear Linear (1 method) (1 Linear Linear (100 methods) (100 Linear 0
100 be not 20 Latency in microseconds in Latency
y ma demuxing Active { 40
static but compatible, 60
100 is solution gperf { 80
erratic 100
oo to is hashing Dynamic { 120
costly 140
oo to r fa is rch sea r Linea {
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 27 Louis St. , y Universit ashington W
patterns.ps.gz
schmidt/ORB- www.cs.wustl.edu/
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
26 Louis St. , y Universit ashington W
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 29 Louis St. , y Universit ashington W
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28 Louis St. , y Universit ashington W
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 31 Louis St. , y Universit ashington W
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
30 Louis St. , y Universit ashington W
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 33 Louis St. , y Universit ashington W
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ORB CORE CORE ORB ORB ORB CORE CORE ORB ORB
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O A T in attern P r Reacto the Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
32 Louis St. , y Universit ashington W
infrastructure demux
changing without
applications Extending {
thread
one within eciently
Handler Handler
select()
events Demuxing {
Event Event
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demuxing/dispatching owns uses
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event synchronous
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h.handle_event(type)
handle_events()
foreach h in handlers loop handlers in h foreach
Initiation Dispatcher Dispatcher Initiation Initiation Intent (handlers); select
attern P r Reacto the with Demuxing Enhancing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 35 Louis St. , y Universit ashington W
ocessing ro p service subsequent from
initialization handler service and establishment connection Decouple {
Intent
Structure r Connecto Structure r Accepto
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handle_input()
complete() open()
open()
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
34 Louis St. , y Universit ashington W
IOP I , e.g. col roto p y erabilit interop ORB subsequent the from
initialization handler connection GIOP and establishment connection
passive/active decouple to pattern r r-Connecto Accepto the Use {
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 37 Louis St. , y Universit ashington W
yle st rogramming p OO an using erations op
server concurrent multiple w allo to pattern Object Active the Use {
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rogram p to rd ha very be can Multi-threading {
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often re a ORBs Reactive since needed re a ORBs Multi-threaded {
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
36 Louis St. , y Universit ashington W
es mistak common avoid 2 and reuse and y rtabilit po rove Imp 1 {
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endpoint endpoint
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client client
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Strategy
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endpoint endpoint Cached Cached Strategy
client client
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server server
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CORE CORE ORB ORB () 6: 1: operation() 1: DISPATCH
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O A T in attern P r r-Connecto Accepto the Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 39 Louis St. , y Universit ashington W
etc. er-Rate, Thread-p ol, o P Thread er-Request, Thread-p Connection,
hedper- Thread-p , e.g. Objects Active of riants va several rts o supp O A T
O A T IOP I SunSoft
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endpoint endpoint
endpoint endpoint
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server server
Connection Connection
Strategy Strategy
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select() select() select() 2a: Task::activate() Task::activate() 2a: 2a:
ORB CORE CORE ORB ORB ORB CORE ORB CORE ORB
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O A T in attern P Object Active the Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
38 Louis St. , y Universit ashington W
strategies concurrency
exible ermit P {
perations op
CLIENTS CLIENTS remove() Representation Representation
FROM FROM
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l cking blo w Allo { Resource
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n
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of thread the from Scheduler Scheduler
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thread the Decouples { }
Interface Interface
resource_rep) m', ( dispatch
Client Client = actQueue.remove() = m' Intent { loop
attern P
Object Active the with Concurrency ORB Enhancing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 41 Louis St. , y Universit ashington W
inversion y rit rio p and overhead Minimizes {
access
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each r fo overhead
ocking lo incurring
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retrieve to oint p
access global
INDEXED BY KEY BY INDEXED
logically one TABLES OBJECT THREAD-SPECIFIC
use to threads
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multiple ws Allo {
THREAD B B THREAD THREAD THREAD A A THREAD THREAD
Intent
attern P rage Sto
hedS eci c Thread-Sp the with cking Lo ORB Minimizing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
40 Louis St. , y Universit ashington W
inversion y rit rio p and contention ck lo minimize and y exibilit
hedn-odel threading-mo maximize to pattern rage Sto eci c Thread-Sp the Use {
Solution
costs cking lo di erent yield schemes concurrency Di erent {
inversion y rit rio p r fo otential p increase cks Lo {
overhead rmance erfo p increase cks Lo {
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serialize to required cking lo of amount the minimize to rtant o imp is It {
Problem
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with Inversions y rit Prio and Contention ck Lo Reducing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 43 Louis St. , y Universit ashington W
strategies ORB
\pluggable" rently transpa multiple rt o supp to pattern Strategy the Use {
Solution
dimensions related many has often y Flexibilit {
non-extensible and static o to re a y exibilit ORB r fo schemes c ho Ad {
rces o F
applications and end-users of es yp t di erent
many of requirements the satisfy to exible be must ORBs rld o Real-w {
Problem
Challenges y Flexibilit ORB Addressing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
42 Louis St. , y Universit ashington W
COMMUNICATION LINK COMMUNICATION
SUBSYSTEM SUBSYSTEM O /O I I/ SUBSYSTEM I/O
) HZ HZ) (1 (1 ) HZ HZ) (5 (5 ) HZ HZ) (10 (10 ) HZ HZ) (20 (20 HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ HZ
REACTOR REACTOR REACTOR REACTOR REACTOR REACTOR REACTOR REACTOR 20 10 5 1 1 5 5 10 10 20 20 1 1 5 5 10 10 20 20 1 1 5 5 10 10 20 20
R 3 2 1 R 3 2 1 R 3 2 1 R R 3 3 2 2 1 1 CONNECTOR CONNECTOR CONNECTOR CONNECTOR CONNECTOR CONNECTOR
O T T T O T T T O T T T O O T T T T T T
T C C C T C C C T C C C T T C C C C C C
CORE CORE ORB ORB CLIENT CLIENT
P E E E P E E E P E E E P P E E E E E E
E N N N E N N N E N N N E E N N N N N N
C N N N C N N N C N N N C C N N N N N N
C O O O C O O O C O O O C C O O O O O O
STUB STUB STUB
A C C C A C C C A C C C A A C C C C C C
CORE CORE ORB ORB SERVER SERVER CLIENT APPLICATION CLIENT
O A T in rage Sto eci c Thread-Sp Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 45 Louis St. , y Universit ashington W
O A T IOP I SunSoft
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lock...
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DEMUXING
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......
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
44 Louis St. , y Universit ashington W algorithm_interface()
rithm algo an
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with state ciating Asso { Concrete
rently transpa
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Strategy Strategy Intent STRATEGY
attern P Strategy the with y Flexibilit ORB Enhancing
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 47 Louis St. , y Universit ashington W
strategies
of y compatibilit
semantic Ensures {
Product_B
strategies Product_B
Abstract Abstract Product_B2 Product_B2 Product_B1 Product_B1
many of customization
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Factory_2 Factory_2 Factory Factory Factory_1 Factory_1
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an con gure to used
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Product_A2 Product_A2 Product_A1 Product_A1
Product_A Product_A
Abstract Abstract
Intent
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
46 Louis St. , y Universit ashington W
con gurations compatible semantically into strategies
ORB multiple consolidate to pattern ry acto F Abstract the Use {
Solution
con gured re a
strategies compatible semantically of groups that ensure to rd ha It's {
strategies con gured individually of ers numb rge la manage to rd ha It's {
rces o F
re nightma
con guration a create can pattern Strategy the of use Agressive {
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 49 Louis St. , y Universit ashington W
dynamically onents comp
ORB desired the assemble to pattern r Con gurato Service the Use {
Solution
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run-time
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rces o F
inecient and in exible is
con guration ORB r rticula pa a to ourselves committing Prematurely {
Problem
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
48 Louis St. , y Universit ashington W
Dispatching Dispatching Demuxing Demuxing
Rate-based Rate-based Active Active
Strategy Strategy Strategy Strategy
Demuxing Demuxing Dispatching Dispatching
Factory Factory
Hashing Hashing Dispatching Dispatching
Factory Factory
Factory Factory
Concrete Concrete
Perfect Perfect FIFO FIFO
Concrete Concrete Abstract Abstract
Imaging Imaging
Avionics Avionics Server Server
Medical Medical
ORB ORB
Rate Rate Connection Connection
per- per- per- per- Strategy Strategy
Thread- Thread- Thread- Thread- Concurrency Concurrency
O A T in attern P ry acto F Abstract the Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 51 Louis St. , y Universit ashington W
Con guration Run-time
Concurrency Concurrency
Factory Factory Repository Repository Connection Connection
Concrete Concrete Service Service Thread-per Thread-per
Avionics Avionics
Dispatching Dispatching Demuxing Demuxing Concurrency Concurrency
FIFO FIFO Active Active Rate Rate
Hashing Hashing Thread-per Thread-per
Perfect Perfect
Factory Factory
Concrete Concrete
Dispatching Dispatching
PROCESS PROCESS
DLL DLL S S
Imaging Imaging Rate-based Rate-based TAO TAO
Medical Medical
O A T in attern P r Con gurato Service the Using
ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
50 Louis St. , y Universit ashington W
}
initialization... Perform //
re con guration
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argv ; argc, tao Service_Config
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utilization
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con gured
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time from strategies resume() suspend()
ORB Decouples { fini()
init() Repository Repository
services Service Service Service Intent Service
attern P r Con gurato
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 53 Louis St. , y Universit ashington W
& &
CLIENT CLIENT SERVER SERVER
ORB CORE ORB CORE ORB
OBJECT ADAPTER OBJECT OBJECT ADAPTER OBJECT
Reactor Reactor Reactor Reactor
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Strategy Strategy
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
52 Louis St. , y Universit ashington W
IOP I SunSoft and
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas 55 Louis St. , y Universit ashington W
rt o supp QoS etter b much rovide p will ORBs of next-generation The
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ORBs Real-time rmance, erfo High-p Schmidt C. Douglas
54 Louis St. , y Universit ashington W
optimizations compiler de eCo yp T {
generation stub optimized and compiler IDL {
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requests of scheduling Dynamic {
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rk o W uture F
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ORBs Real-time rmance, erfo High-p cus: o F Current
ry Summa Project O A T
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