ns2 project in Alabama

    ns2 project in Alabama the protocols introduced are based on the following

general assumptions: 1. Nodes within a cluster are fully connected (e.g.,

nodes under leader 2, 3, or 4), including nodes

belonging to different subtrees (e.g., all nodes under

leader 3 are fully connected). 2. In some cases, nodes from different ns2 project in Alabama clusters (or

machines) may not see each other directly (e.g., nodes

under leader 2 cannot see nodes under leader 3). 3. All machines in the system must be fully connected

in the sense that at least one node from each ns2 project in Alabama machine

can see at least one node from each of the other

machines. Before getting into the details of the ns2 project in Alabama structure and

required mechanisms, we define some basic terms that will

be used throughout this section. Virtual cluster: A collection of nodes within one

large cluster that form one group of agents and ns2 project in Alabama their

leader (a subtree). A large cluster is divided into

multiple virtual clusters to make communications

and management more efficient (e.g., the agents led

by leader 4 in . 2. Head node: In some cases, a cluster has a ns2 project in Alabama single node

that is connected to other machines or clusters. This

node is called the head node and has a leader agent

residing on it. 3. Local node: From the viewpoint of an agent/leader,

the node where it resides is its local node. 4. Remote node: From the viewpoint of an agent/

leader, nodes other than its local node are remote

nodes The protocols introduced here require a number of standard

control messages that the agents use to communicate and

exchange information. These messages, referred to ns2 project in Alabama as the

middleware control messages (MCM), are defined here. Leader Advertisement Message (LAM): A broadcast

message sent by a newly created leader to inform

other existing leaders of its birth. LAM contains the

leader’s ID (a unique identifier acquired at startup) and its address ns2 project in Alabama information. 2. Agent Monitor (AM): Periodic messages sent by leaders to one another and to descendant agents to

check if they still exist. 3. Leader Advertisement Acknowledgment Message (LAAM): Sent by a leader upon receiving a LAM or AM from another leader. LAAM contains respondent’s ID and address ns2 project in Alabama information. 4. Agent Activation Message (AAM): Sent by a leader to activate descendant agents. It contains the leader’s ID and address information, in addition to an activation command. 5. Agent Monitor Acknowledgement (AMA): Sent by an agent in response to an AM or AAM. It contains the sender’s ID, address, and resources information.

6. Leader Not Responding Message (LNRM): Sent by a leader that ns2 project in Alabama does not receive an LAAM from another leader in response to the AM message, to all leaders at the same level, and the leader’s parent if one exists. It contains the sender’s ID and the nonresponding

leader’s ID.

For the agents to operate efficiently, they need a ns2 project in Alabama  startup

protocol to automatically identify and communicate with

one another. The initial stage requires manual installation of

the first leader agents on the head nodes. The ns2 project in Alabama leaders then

start the startup and automatic configuration phase.

1. Each leader is responsible for performing the

following tasks: a. Execute the startup protocol to automatically

acquire connectivity and operational information

in the system. b. Periodically perform availability checks of the

leaders and descendant agents. If a leader or

agent does not respond, activate leader recovery

or agent update protocols. c. Perform object routing for other agents to ensure

full connectivity with other clusters and machines

in the system. Many routing protocols

can be adapted for this system, but the discussion

of the routing details is beyond the scope of

this paper.

ns2 project in Iowa

      ns2 project in Iowa nevertheless,

this policy can be adapted to provide different levels of access control on the available machines. For

example, a user on a cluster is given full access to all ns2 project in Iowa cluster

nodes, but limited access to external systems. Another

example is deploying an authentication/authorization

policy for different access modes on the participating ns2 project in Iowa machines. In this section, we introduce and analyze a framework for an automated startup and configuration mechanism for a

hierarchical structure of the distributed agents in the system.

The startup stage is essential to guarantee the accurate and

efficient operation of the middleware infrastructure and the

applications using it. The main goal here is to provide system

startup and configuration with minimum user ns2 project in Iowa involvement. Anumber of issues such as how the agents are connected and

how they view one another are considered. The mechanism

for adding and removing agents from the system and their effect on the configuration are also studied. Three protocols

are introduced for automatic startup, leader recovery, and agent update. The distributed agents in the system need to communicate among themselves to perform their required operations.

However, the structure in which these agents are ns2 project in Iowa organized

has a strong impact on how efficient they operate. Within a

single cluster or a limited number of machines participating

in the system, a linear structure is sufficient for the agents to

communicate and achieve their functionality. However, this

requires agents to be fully connected, which may not

always be possible. In addition, the linear ns2 project in Iowa structure causes

considerable delays for some operations that need to be

performed on all participating machines. To overcome these

limitations, we designed a hierarchical structure where

agents have multilevel connections in the system. Generally,

a networked heterogeneous system composed of

clusters and multiprocessor machines ns2 project in Iowa forms the top level

of the hierarchy. Within each of these machines or clusters,

one or more levels may be formed, depending on the type

of machine and number of nodes/processors in it.

Leader agent (called leader hereafter): An agent that

manages and controls a set of other agents ns2 project in Iowa under its

control. Leaders at the same level communicate with

one another directly. 2. Regular agent (called agent hereafter): An agent that

performs the regular agent operations. Agents under

the control of the same leader should be able to

communicate with one another and their leader

directly. In addition, agents in different layers, but in

the same physical cluster (with direct links between

the nodes) communicate with one another directly. hierarchical structure

of a networked heterogeneous system, ns2 project in Iowa which we will refer

to in the rest of this section. The squares denote leader

agents, while the circles represent agents. Some ns2 project in Iowa machines

such as SMP (symmetric multiprocessing) or MPP (Massively

Parallel Processing) machines need a single agent to

handle the resources (e.g., leader 1), while others such as

clusters need an agent for each node. The connecting lines

represent bidirectional communication links between

nodes. However, at the top level of the ns2 project in Iowa hierarchy, the links

between leaders (e.g., 1, 2, and 3) may be a multihop path.

ns2 project in Nevada

     ns2 project in Nevada the client services class uses two types of classes for

communication between clients and agents and among

agents. The agentClient provides APIs to manage, control,

and send requests for an agent and it is  ns2 project in Nevada used for direct

communication between the client and a given agent or

among agents. In addition, the agentGroup provides APIs to

manage, control, and send requests for a group of agents

using the agentClient to individually ns2 project in Nevada communicate information

to all agents in the group. For example, when a job is

initiated, the request and schedule objects are ns2 project in Nevada passed to the

agentGroup, which uses the agentClient to pass them to

individual agents. Both agentClient and agentGroup are also

used as API for developing distributed applications. When

a programming model is developed using the runtime

support environment, the interprocess ns2 project in Nevada communications are

handled in different ways. Point-to-point communications,

for example, can be implemented directly by the ns2 project in Nevada programming

model. However, if the nodes/machines involved are

not within a single cluster, the agents can assist ns2 project in Nevada the

communications by providing routing mechanisms between

the different nodes. In addition, group communications

such as broadcast and multicast can be provided by

the runtime environment rather than the programming

model to achieve efficient distribution and ns2 project in Nevada response times. The system allows multiple users to execute multiple jobs

simultaneously. To properly manage these jobs, each job

has multiple levels of identification, starting with a unique

job ID assigned by the system. The user ID and the program

name further distinguish different jobs. Within each job,

thread IDs are used to identify the remote threads of the job.

Executing user threads on remote machines ns2 project in Nevada exposes these

machines to many “alien” threats, raising security and

integrity concerns. Therefore, these machines must be

protected to ensure safe execution. Java’s default security

manager provides some level of protection by checking

operations against defined security policies ns2 project in Nevada before execution.

However, the security manager in Java has some

restrictions, thus many functions have been modified or

rewritten for our system. More specifically, two modes of

execution are used to provide a robust and secure

environment: 1. The Agent Mode in which no restrictions are

imposed. A thread running in this mode has full

control of all the resources and operations in the

system. All agents run in agent mode. 2. The User Mode in which restrictions are applied to

limit the user access to the system resources. Some

operations, such as deleting files, creating a ns2 project in Nevada subprocess,

using system calls, modifying system properties,

and writing files, are disabled in this mode.

With the security modes in place, the user processes have

full access to resources on their local machines (where the

user job was initiated), but limited and controlled access to

all remote machines’ resources (since they are running in

user mode). To provide users with access to necessary

resources for their application, the root (master) process

executes on the user’s local machine. However, the ns2 project in Nevada user has the option to override this setting and allow the root process

to execute on a remote machine; however, the application

will have limited access to the system’s resources.

ns2 project in Arizona

       ns2 project in Arizona our middleware infrastructure ns2 project in Arizona utilizes software agents to provide flexible and expandable middleware services for

high-performance Java environments. The main functions

of the agents are to deploy, schedule, and support the

execution of the parallel/distributed Java code, in addition

to managing, controlling, monitoring, and ns2 project in Arizona scheduling the

available resources on a single cluster or on a collection of

heterogeneous systems. When a parallel Java application is

submitted, an agent performs the following tasks: 1. Examine available resources and schedule the job for

execution, while balancing the load. 2. Convert ns2 project in Arizona scheduled user classes into threads, then

remotely upload and execute them directly from the

main memories on the remote machines. 3. Monitor and ns2 project in Arizona control resources and provide monitoring

and control functions to the user. For high throughput, the agents are multithreaded,

where each thread serves a client’s request. Once user ns2 project in Arizona threads are deployed, they directly communicate with one

another to perform parallel tasks, thus freeing the agents and reducing the overhead on the user programs. Agents’

communication mechanisms are implemented using sockets

and each agent consists of a number of components

whose main functions are described below, although many

of these functions can be independently ns2 project in Arizona enhanced to

provide different levels of services.

The Request Manager handles user job requests

such as deploying classes, starting/stopping a job,

and checking agents/threads status. Requests come

as request objects from client services or from

other agents. 2. The Resource ns2 project in Arizona Manager provides methods to manage,

schedule, and maintain the resources of the

machine where the agent resides. It keeps records of

executing threads, machine and communication

resources’ utilization, and performance information.

In addition, it is responsible for ns2 project in Arizona reclaiming system

resources after each job’s completion or termination. 3. The Security Manager provides security measures

for the system (see Section 4.3 for details). 4. The Class Loader remotely loads user classes in

parallel onto the JVMs on the remote machines in

preparation for execution. 5. The Scheduler selects the machines to execute a user

job based on the requested number of processors.

One mechanism to generate a schedule is ns2 project in Arizona to execute

a test program to select the fastest responding

machines. This method provides a simple but basic

load balancing among the processors. However,

since this is an independent ns2 project in Arizona component, the scheduler

can be easily replaced by any suitable

scheduler to satisfy different policies and performance

requirements. The client servicesand environment APIs providecommands

for users to interact with the environment. Requests are

accepted from the user and passed to the agent after

encapsulation as an object with the ns2 project in Arizona necessary information.

The following commands are available for the user through

client services and for the other programming models and applications as APIs such as pjava to initiate a parallel job,

pingAgent to list available agent(s) and their status, listThreads

to list active threads, and killJob to terminate a job

ns2 project in South Dakota

      ns2 project in South Dakota while a user is allowed to run a program on a remote

node, he/she should not be allowed to access any

files on the remote nodes or change their system

properties without proper authorization. Although ns2 project in South Dakota basic security mechanism is available in Java to

protect selected node resources, it would nevertheless

be preferable if advanced security functions

were available so that access control and security

protocols can be easily defined and enforced

through the middleware. Job and Thread Naming: For an environment supporting

multiple parallel jobs, a unique job ID needs to

be assigned to each active job, which is needed to

control a specific job, for example, to kill a job. In

addition, each parallel job ns2 project in South Dakota consists of multiple

threads distributed among the nodes; therefore, a

thread ID is needed for each thread. The thread ID is

used to distinguish threads and ns2 project in South Dakota control the flow of

the parallel programs such as in ns2 project in South Dakota message passing.

For user threads to communicate, a mechanism to

provide a mapping between logical ns2 project in South Dakota thread IDs and

actual network addresses such as IP address and

network port is needed. User Commands: Users need commands to submit,

execute, and monitor their parallel programs and to

control the environment from a single point on the

cluster. Examples of these commands are to check

available resources and currently running parallel

jobs. These commands should ns2 project in South Dakota provide the user with

a single system image Any parallel application

requires some form of synchronization and control

to function correctly. Executing parallel applications on distributed environments makes these needs

even more important. Basic mechanisms to ensure mutual exclusion, ordered execution, and barriers are necessary for many programming models.

A distributed parallel application requires collective communications

at two different levels: at the job (or task) level

to deploy, monitor, and control users jobs, ns2 project in South Dakota and at the

process level for interprocess communications such

as broadcast and multicast. A programming model

can benefit from the middleware for both levels,

where efficient group communications methods can

be utilized. Distributed applications may also require

mechanisms to manage and control real-time

dynamic agent and process membership in the

system. These common requirements can be implemented in

different ways to provide the necessary ns2 project in South Dakota tools and APIs for

the programming model developer to build any of the

aforementioned programming models. However, each

model will also have its own set of functionalities that

need to be implemented as part of ns2 project in South Dakota the programming model

itself. For example, in a distributed shared memory or object

model, issues such as coherence and consistency must be

handled within the programming model ns2 project in South Dakota and independently

from the middleware, while in a message passing model, it

is left for the application developer to handle. In addition, some programming models can implement some functions

already available in the middleware to achieve specific

goals. For example, the communications functions in a

message-passing model can be realized using the ns2 project in South Dakota middleware

functions or directly in the model to support

specialized communications services that come with advanced

cluster networks such as the Sockets-GM for

Myrinet The middleware infrastructure is designed to satisfy the

requirements discussed above. This system ns2 project in South Dakota provides a pure

Java infrastructure based on a distributed memory model,

which makes it portable, secure, and capable of handling

different programming models (see Fig. 1) such as JOPI [23]

and the DSO model. The system has a number of

components that collectively provide middleware services,

including some of the requirements ns2 project in South Dakota described above, for a

high-performance Java environment on cluster and heterogeneous

systems. Software agent technology has been used in many systems

to enhance the performance and quality of their services

ns2 project in Nebraska

        ns2 project in Nebraska the first approach introduces a new JVM that recognizes the existence of multiple

machines and utilizes them to execute the Java bytecode in parallel. This JVM should ns2 project in Nebraska handle the distribution of load and data/objects and efficiently utilize available resources. However, such JVM may

be inefficient since many sequential applications are

not easily parallelizable, especially if they were

designed without parallelization in mind. Using preprocessors usually ns2 project in Nebraska involves restructuring the

existing Java code or bytecode to a parallel format. This process could be done either by parallelizing

substructures such as loops or by introducing a different ns2 project in Nebraska parallelization model such as messagepassing

or DSM in the code. In both cases, the main

goals are to relieve the developer of the burden of explicitly ns2 project in Nebraska parallelizing the application and to run current applications in parallel without (or with minor) modifications. Again, the programming

model should be able to execute the automatically

generated parallel programs. This ns2 project in Nebraska model could be

built from scratch or by utilizing any of the

programming models described above. However,

the efficiency achieved is not ns2 project in Nebraska very high because

applications vary and the systems cannot handle all

of them at the same level of efficiency.

In addition to these four ns2 project in Nebraska categories, a few research

groups have also used combinations ns2 project in Nebraska of these models or

selected functionalities to provide different methods of

parallelization. Although the message-passing model is the

most difficult from a user’s ns2 project in Nebraska perspective, it is usually the

most efficient because it is directly based on the system’s

basic communication mechanisms.

However, the automatic ns2 project in Nebraska parallelization is still the most attractive option for users

since it does not involve any effort from them. Nevertheless,

it is very difficult to achieve and the existing systems are not

efficient. Detailed information about ns2 project in Nebraska the classification,

implementations, and comparison of parallel Java projects

for heterogeneous systems can be found in .Standard Java technology such as JVM and JINI [15]

provide a variety of features to develop and implement

distributed Java applications. However, there are some key Loading User Programs onto the Remote JVMs on the

Participating Machines: Java does not provide mechanisms

to remotely load user classes on more than

one JVM in parallel. A parallel application ns2 project in Nebraska needs to

be loaded onto JVMs of all nodes where it is

scheduled. Thus, the parallel Java environment

needs mechanisms to remotely load classes onto

the selected nodes before starting the execution of

the parallel application.  Managing Resources and Scheduling User Jobs: In order

to efficiently run parallel applications, the system

needs to schedule user programs based ns2 project in Nebraska on the

availability of the nodes and the available resources

in each node. Thus, a mechanism is needed to

monitor, manage, and maintain the resources of the

entire cluster(s). Resources on a node may include

the number of idle or sharable processors, memory

space, current workload, the number ns2 project in Nebraska of communication

ports, and sharable data and objects. Security: Some resources on the cluster nodes or

distributed system may need to be protected from

remote jobs being executed locally.

ns2 project in Indiana

      ns2 project in Indiana they are described below

in decreasing level of user involvement and system efficiency. 1. Message Passing: In this category, the system

provides some form of information exchange mechanism among ns2 project in Indiana distributed processes. It provides,

for example, functions to exchange messages among processes with point-to-point and group communication primitives, synchronization, and other operations. This programming model handles the

remote process deployment and message exchange among the ns2 project in Indiana participating machines.  The runtime

support can be implemented as an independent middleware layer, thus providing a flexible and expandable solution. On the other hand, it can be implemented as an integral component of the model, ns2 project in Indiana thus making it more tightly coupled with the required functionality. However, the first approach is more flexible, expandable, and can be easily enhanced to support other models. The messagepassing library and runtime support can be ns2 project in Indiana implemented

in different ways such as pure Java implementations based on socket programming, native ns2 project in Indiana marshaling, and RMI [27], or by utilizing Java native interface (JNI), Java-to-C interface (JCI),

parallel virtual machine (PVM), and other parallel infrastructures. A number of projects tried to comply with MPI [29] and MPJ [13], while others were based on a new set of APIs. Models in this category

provide an efficient parallel programming ns2 project in Indiana environment

because they directly utilize the basic communication

mechanisms ns2 project in Indiana available; however, they are

the least user friendly and require full user awareness

of the parallelization process.

In the distributed shared ns2 project in Indiana address space or distributed shared object

(DSO) model, the model presents an illusion to the

user of a single address space where all or some

data/objects are available to all ns2 project in Indiana participating processes.

To provide this illusion, the programming

model should be able to transparently handle all

data/object communication, sharing, and synchronization

issues, thus freeing the user from the

concerns of operational details. One method of

implementation is to utilize an available messagepassing

infrastructure. However, the programming

model should handle the different issues of shared

space such as information (data or objects) integrity

and coherence, synchronization, and consistency.

This category provides a more ns2 project in Indiana friendly development

environment of parallel applications; however, the

performance is penalized due to the overhead

imposed by the sharing (coherence and consistency)

and synchronization requirements. 3. Automatic Parallelization of Multithreaded Applications:

This category aims to provide seamless

utilization of a distributed environment to execute

multithreaded applications on multiple machines The main ns2 project in Indiana goal is to execute concurrent multithreaded

applications in parallel without modifications. In this case, the implementation issues are

similar to those in the distributed shared address space model ns2 project in Indiana in the sense that all data and objects

used by more than one thread need to be sharable. As a result, the programming model requires data

sharing or data exchange mechanisms to provide thread distribution and information sharing. To

implement this model, a message-passing system or a DSM/DSO system can be used as the underlying

support mechanisms. Such system is less efficient than a ns2 project in Indiana message passing due to the additional

overhead of handling remote thread deployment, sharing, and synchronization. 4. Transparent (Automatic) Parallelization: Here, the goal is to execute sequential applications in parallel on multiple machines. Some systems provide transparent

parallelization of Java programs ns2 project in Indiana written in standard Java by modifying the JVM, while others

utilize preprocessors.

ns2 project in Alaska

   ns2 project in Alaska projects such as

Titanium  and HPJava  provide Java dialects

for parallel programming with their own compilers,

while others such as JAVAR [6] and JAVAB

provide parallelizing precompilers. Alternatives to ns2 project in Alaska JVM. These projects provide parallel

Java capabilities by altering the JVM or building a

new one. Examples include JPVM [16] and cJVM.

Mechanisms that enable multithreaded ns2 project in Alaska applications to

transparently utilize the underlying multiprocessor

hardware are incorporated in projects of this

category. This approach requires that the system

distribute the threads among the ns2 project in Alaska distributed processors

without user involvement. Representative

projects include cJVM [4], JavaParty [26], and

ProActive [11]. 4. Pure Java implementations. Projects in this category

provide parallelization facilities in pure ns2 project in Alaska Java implementations,

which make the system portable and

machine independent. Such systems require class

libraries to provide the APIs needed to write parallel

Java applications. ParaWeb [8], Ajents [20], Babylon

[19], and JOPI [23] are some of the examples.

Our literature review [2] revealed that many research

groups are working toward providing ns2 project in Alaska tools and programming

models for parallel Java. Many of the projects provide

message-passing interfaces based on MPI and MPI for Java

(MPJ) draft specifications [13]. However, our approach to

providing parallel-programming capabilities in Java has

several differences from the projects studied. One significant

difference is the separation of the ns2 project in Alaska enabling mechanisms,

i.e., the middleware infrastructure, from the parallel

programming models resulting in many advantages: The infrastructure supports different programming

models such as message-passing, object-passing, and

distributed shared object. 2. The infrastructure provides efficient common services needed by any programming model such as scheduling, monitoring, load balancing, ns2 project in Alaska synchronization, and job control. 3. The programming models can be easily changed, upgraded, or completely reengineered without having

to change the underlying support mechanisms.

4. The organization of the infrastructure and its ns2 project in Alaska close relationship with the models provides the flexibility

to optimize and fine-tune its operations to achieve

good performances. Based on our observations from studying the different approaches for parallel programming in Java, we have identified some common requirements. In this section, we

first discuss the different parallel Java programming ns2 project in Alaska models and study the requirements to implement and deploy these

models, then identify the generic services and functions that the middleware should provide for developing and

supporting the different programming models. Providing parallel ns2 project in Alaska programming capabilities in Java can be

achieved by following the known parallel programming models. These models are divided into four layers

(categories) based on the level ns2 project in Alaska of user involvement in the parallelization process and the achievable levels of efficiency. In addition, the implementation dependencies can

be observed among these layers.

Ns2 project in South Carolin

Ns2 project in South Carolina  the main objective of the paper is to identify the common requirements for the parallel and distributed programming models and to propose and design a middleware infrastructure to satisfy these requirements. In addition, the paper discusses ns2 project in  South Carolina a framework for the distributed agents’ organization, configuration, and communication mechanisms to provide efficient, flexible, and scalable system support.

Requirements such as ns2 project in  South Carolina remote loading and execution, resource management and scheduling, naming, security, group management and communications, and synchronization ns2 project in  South Carolina mechanisms were identified Furthermore, the middleware infrastructure is ns2 project in  South Carolina designed to satisfy these requirements in a multilayered modular manner, which separates the programming model’s specific functionalities from the general runtime support required by any parallel or distributed programming model. The layered approach also allows for easy ns2 project in  South Carolina modifications and updates of the different functions and services at the different layers and provides flexible component-based plug-ins.

Therefore, the individual details of the middleware infrastructure components such as the ns2 project in  South Carolina scheduler, resource manager, etc., can be separately considered as plug-in components. Moreover, the pure Java infrastructure based on distributed memory model provides portability, security, and the ability to utilize heterogeneous systems. In the rest of this paper, Section 2 reviews related work and concepts. Then, we discuss parallel Java programming models and identify common infrastructure ns2 project in  South Carolina service requirements on clusters and heterogeneous systems in Section 3. In Section 4, we describe the architecture and features of the infrastructure and introduce the agent start-up organization and communication mechanisms in Section 5. Section 6 presents an example, the Java Object-Passing Interface (JOPI), that utilizes the middleware, along with the experimental evaluation of the performance.

Finally, Section 7 concludes the paper with ns2 project in  South Carolina remarks about the main features and advantages of the middleware infrastructure and the current and future work. Java’s popularity among developers is increasing steadily and many research groups are exploring the possibilities of using Java for high-performance parallel computing on multiprocessor systems. Since Java is machine independent, the same Java programs can run on any platform with a Java virtual machine (JVM), without recompilation for each platform. In addition, Java is constantly being improved and optimized for performance. Very recently, research groups have worked on providing parallel Java using different approaches and programming models. This section introduces related concepts and lists some related projects. Java, in its current state, provides features and classes that facilitate distributed application ns2 project in  South Carolina development. Some of the features are object serialization , remote method invocation (RMI) , class loaders, network programming and Sockets, and the reflection API. However, the development process of parallel applications in Java is complex and time consuming.

Using the currently available methods, a daring programmer may be able to write a parallel application in Java, but the complexity of the task deters almost all from tackling this ns2 project in  South Carolina intricate task. On the other hand, the message-passing interface (MPI)  has  provided languages such as C and FORTRAN with slightly simpler APIs to write parallel programs. Other MPI-based APIs such as OOMPI , provide object-oriented message-passing interfaces. Many ns2 project in  South Carolina projects investigating parallel Java capabilities are in the research phase. Extensive literature study led us to classify them into the following four different categories based on how they provide parallelism, their compatibility with the JVM, and user involvement.

ns2 project in Rhode Island

           ns2 project in Rhode Island the parameters show that critical activity 1 of critical transaction

0 is placed in processor 2. Figure 15 shows the use

of this processor by each transaction in the critical activity ns2 project in Rhode Island

window. Transactions 2 and 10 are observed in strong

competition with transaction 0 during the execution of its

critical activity. A new mapping with motor tasks motor[2]

and motor[10] in processor 3 eliminates ns2 project in Rhode Island deadline failures in

all transactions. A methodology for performance debugging of parallel

and distributed embedded systems based on ns2 project in Rhode Island measurement

has been presented. The methodology was designed as

an alternative to the conventional static analysis approach

based on scheduling for complex non-critical embedded

systems. The approach followed by the methodology models

the PDES as a set of real-time transactions, giving response

to the action events. The possibility for the transactions

to have not only a pipelined structure but also a parallel structure, is

another important feature that is supported. The methodology

involves the construction of a synthetic prototype ns2 project in Rhode Island for

the initial design of the PDES, which is refined until the final

implementation. This refinement is carried out in two

repeated steps: the diagnosis of temporal behaviour and the

configuration of the PDES prototype. These steps are based

on a set of parameters and metrics covering three complementary

views of the PDES: the behavioural view, the structural

view and the resource view. Several cases with different numbers of processors have

been analyzed and configured with the methodology, one of

which is presented in this paper. Although not all ns2 project in Rhode Island the causes

of behaviour considered in the methodology were covered

by these cases, the fulfillment of the real-time constraints

after the configuration steps have demonstrated the validity

of the methodology. Future work has two main objectives. Firstly, to derive

automatic rules for proper configuration of PDES using the

expertise gained with the use of themethodology. Secondly to apply the methodology to PDES based on POSIX and

implemented on shared memory parallel ns2 project in Rhode Island architectures. The cluster system includes one host server, four slave

servers and some clients. The host, slaves and clients linked, There are five key techniques in this system. The dishibuted

database, parallel virtual machine, buffer and

synchronization techniques in communication and multithreading in control flow. The face database in this system is so huge that ha thousands human face. Single computer. Withlimited ns2 project in Rhode Island hardware resource and performance can be hardly competent for content based query in face recognition

system. Single computer style bas two problems, one is the

query speed and the other is the capability of face database.

There are two measures to solve these problems, one is adopting high performance computer such as work station

and huge machine, the other is building network distributed

system using multi ordinary PCs. The latter is adopted in ns2 project in Rhode Island  this system because of high performance price ratio and good extensibility. Message transfer based distributed system has a communication bottleneck. To decrease communication spending, the main face database was split ns2 project in Rhode Island into fivesub-datahases. So only the face feature data to he queried

should be transferred between the main server and slave

server, also between the client and the main server Where ns2 project in Rhode Island MFDB represents the main face database, SFDB is

the sub-database, and SFDBi is the ith sub-database. Figure 2 shows the split process. The PC cluster used in face recognition system forms a parallel virtual machine. And a single host and multi slave

structure adopted. The parallel virtual machine was set up by host, and a ns2 project in Rhode Island  parallel virtual machine table was built and

preserved by host, The parallel virtual machine table is a linked tahle. The host node holds the face feature database and document information database. And slaves hold the ns2 project in Rhode Island name, their IP address and subface database. The linked table structure permits to add slaves infinitely and also delete a slave very conveniently, just let the pointer point to another slave.