Replica System in Distributed File Sharing Environments

Replica System in Distributed File Sharing Environments AN EFFECTIVE FRAMEWORK FOR MANAGING REPLICA SYSTEM IN DISTRIBUTED FILE SHARING ENVIRONMENTS Tesmy K Jose,  Ã‚  Dr.V.Ulagamuthalvi Abstract-An Enhanced file system called Probabilistic File Share System is used to resolve all the distributed file update issues. There are three mechanisms designed in the probabilistic file share system such as Lazy Adaptive Synchronization Approach, Standard Replica System Replay Approach and Probabilistic method. The adaptive replica synchronization and Standard Replica System Replay approaches are implemented among the Storage Servers (SSs) and it makes the Meta Data Server (MDS) free from replica synchronization. Furthermore, a probabilistic control system is deployed into the proposed work in order to managing replicas replacement, overloading and their failures where the system can be measure the possibilities of every replicas replacement, overloading and failures level according their communication overhead and physical information. If the communication overhead or physical failure probability is high then the replica system replaced from replicas environment as well as se nds the notification message to its neighbor replicas with the failure system details. Keywords- Metadata Server, Lazy Adaptive Synchronization, Standard Replica System Replay, Probabilistic Control System. 1. Introduction As the volume of digital data grows, reliable, low-cost storage systems that do not compromise on access performance are increasingly important. A number of storage systems (e.g., libraries, tape and optical jukeboxes) provide high reliability coupled with low I/O throughput. However, as throughput requirements grow, using high-end components leads to increasingly costly systems. In general, the client contacts the metadata server (MDS), which handles all the properties of the whole file system, to get the authorization to work on the file and the information of the file’s layout. Then, the client accesses the corresponding storage servers (SSs), which handle the file data management on storage machines, to execute the actual file I/O operations after parsing the layout information obtained from the MDS. A number of existing distributed storage systems (e.g., cluster-based and peer-to-peer storage systems) attempt to offer cost-effective, reliable data stores on top of unrelia ble, commodity or even donated storage components. To tolerate failures of individual nodes, these systems use data redundancy through replication or erasure coding. This approach faces two problems. First, regardless of the redundancy level used, there is always a non-zero probability of a burst of correlated permanent failures up to the redundancy level used; hence the possibility of permanently losing data always exists. Second, data loss probability increases with the data volume stored when all other characteristics of the system are kept constant One of disadvantage of clusters is that programs must be grouped to run on multiple equipments, and it is difficult for these grouped programs to cooperate or distribute resources. Perhaps the most significant such resource is the file system. In the absence of a cluster file system, individual components of a grouped program must share cluster storage in an unplanned manner. This typically complicates programming, restricts performance, and compromises reliability. Also, the Meta Data Server is responsible for handling all the information about chunk replicas and generating replica synchronization when one of the storage servers has been updated. However, saving the recently written data to the disk becomes a blockage to the whole file system because all other threads need to remain until the synchronous flush-and sync procedure started by one of the SSs is completed. A Probabilistic File Share System is proposed to resolve the abovementioned issues. It is used to support lazy and adaptive replica synchronization with replica replacement management among the SSs and make the MDS free from replica synchronization and failure maintenance. 2. Literature Survey Different types of distributed file system supports chunk replication for reliability and produce high data bandwidth as same as similar replica synchronization mechanisms. A class of file system extends the traditional file server architecture to a storage area network (SAN) environment which allows the file server to access data directly from the disk through (SAN). Examples of SAN file system are IBM/Tivoli SANergy and Veritas SAN Point Direct [8,9]. GPFS allows chunk replication by partitioning space for multiple copies of each data chunk on the different Storage Servers and updates to all locations synchronously. Before the completion of write operation, GPFS used to follow the updates of chunk replicas which files had updated on the primary SSs and then updates other replicas[7].Ceph also had similar replica synchronization policy, i.e., the newly written data should be applied to all replicas stored on the different Storage Servers[5]. In the Hadoop file system, the replicated chunks are stored on the Storage Servers. Storage Server’s list will contains copies of any stripe produced and managed by Metadata Server. So, the Metadata Server handles the replicas synchronization and if new data written on any of the replicas,it will be triggered [4]. In GFS, the Metadata Server computes the location and data layout among the various chunk servers. Every chunk is replicated on multiple chunk servers and the replica synchronization is done by Metadata server (MDS) [6]. In Lustre file system, which is the parallel file system has a same chunk called replication mechanism [10]. The researchers are successively presented MinCopysets and Copysets replication techniques to enhance data durability (i.e., data loss) during retain the benefits of randomized load balancing by using derandomized replicas placement policy. However, researchers didn’t enclose the algorithm of replica synchronization and replica replacement [3,2]. 3. Proposed System 3.1 Probabilistic File Shared System Architecture The probabilistic file share system copy and give out the locations of all replicas belonging to the same file chunk to the Storage Servers (SSs) where the replicas are stored. Fig. 1 shows the architecture of probabilistic file share system. The probabilistic control system is organized to calculate the failure rate of every replica in the probabilistic file share system environment. To calculate the failure rate of replicas, our system examine each replicas for communication overhead and also obtains the CPU and memory utilization. By this our proposed system maintains better data consistency in the distributed file shared environment. Fig. 1 Probabilistic File Share System Architecture 3.2 Data Updating Fig. 2: Adaptive Synchronization Approach In the case of processing a write request, the probabilistic file share system use the mechanism of lazy replica synchronization. This probabilistic system firstly completes the write operation and each update process in probabilistic file share system storage is replicated using adaptive replica synchronization. Here adaptive replica synchronization approach is used to copy the each modification in a storage management of distributed file system where primary replica updates the result into replica n and passes the acknowledgement into primary replica. 3.3 System Crash Handling The probabilistic file share system adopts a deferred replica synchronization mechanism for reconstructing the lost file updates. i.e., it allows only the primary Storage Server to manage the latest data snapshot for reducing write latency and the synchronous process of replica to other SSs will be conducted along the timeline. The Meta Data Server buffers ascertain the latest write requests in the memory; when the number of cached requests is larger than a predefined threshold, the MDS is supposed to direct SSs to perform regular replica synchronization, so that the cached requests can be removed from the memory. 3.4 SS’s Failure and Replacement The proposed file sharing system arranged in a probabilistic control system that examine the system details and every replica communication. The probabilistic control system keeps a replacement list to store the system details such as CPU utilization, Memory Utilization and etc. By using the abovementioned information, the probabilistic control system measures the failure rate for each replica. If the communication overhead or physical failure probability is high then the replica system replaced from replicas environment as well as sends the notification message to its neighbor replicas with the failure system details. Figure 3: Illustrated of Probabilistic Control System The Figure 3 shows the illustrated replica replacement management process. The following function is used to measure the failure rate of replica: 5. Conclusion This research work proposed a new probabilistic file share system. The modified lazy adaptive synchronization approach successfully updates the data in the Storage Servers. This approach will take less I/O execution time, computation and storage compared to other approaches. The standard replica system replay approach can well handle the crashes of Storage Servers and can improve the lost data. At last, a probabilistic control system is positioned in the new probabilistic file share system. The replica failure calculation and their replacement management are extremely directed by the probabilistic control system.

Behavioral Program

Much of real-life behavior is like this: responses are learned because they operate on, or effect the environment. Referred to as an operant conditioning, this kind of learning occurs in human’s species, as well as in lower species. Alone in a crib, a baby may kick and twist and coo spontaneously.When left by itself, a dog may pad back and forth, sniff, or perhaps pick up a ball, drop it, and play with it. In the case study presented, Claire apparently learned that her tantrums had given her the leverage to get what she wants and this definitely is also a picture of operant conditioning in application.Neither organism is responding to the onset or offset of a specific external stimulus. Rather, they are operating on their environment. Once the organism performs a certain behavior, however, the likelihood that the action will be repeated depends on its consequences. The baby will coo more often if each such occurrence is followed by parental attention, just as what happens to C laire, and the dog will pick up the ball more often if petting or a food reward follows this action.If one would think of the baby as having a goal of parental attention, and the dog as having a goal of food, then operant conditioning amounts to learning that a particular behavior leads to attaining a particular goal (Atkinson, 1993). Theoretical framework Instrumental conditioning, in the strict sense, is based on the concept and idea of Burrhus Frederick Skinner or B. F. Skinner. Like John Watson, Skinner insists that psychologists concern themselves only with observable behavior; that is, the psychologist should study behavior as it is and nothing more.Hence, Skinner tried to look for lawful processes in behavior with the use of rats and pigeons (Atkinson, 1993). Operant conditioning may then play a role in attitude formation where parents tend to reward their children for expressing attitudes that coincide with their own and to punish or ignore then for expressing attitudes that deviate from them (Atkinson, 1993). Applications of the theory Applications of operant conditioning to a child focus on the temporal relation between a response and its reinforcer.Laboratory experiments have shown that immediate reinforcement is more effective than delayed; the more time between an operant response and a reinforcer the less is the strength of the response. Many developmental psychologists have noted that the delay of reinforcement is an important factor in dealing with young children. If a child acts kindly towards a pet, the act can best be strengthened by praising (rewarding) the child immediately, rather than waiting until later.Similarly, if a child hits someone without provocation, this aggressive behavior will more likely be eliminated if the child is punished immediately rather than waiting until later (Atkinson, 1993). Allen and Harris (1966) report on a research on the successful elimination of a child’s incessant scratching by first teaching the mo ther the idea behind operant conditioning. Another study though not so related with Claire’s case is the application of instrumental conditioning in motivating oneself to lose weight (Collier, 1969).Reinforcement- is anything that increases the probability that a particular response will increase in frequency. The presentation (positive) or removal (negative) of particular consequences may reinforce responses. Thus, reinforcement may be either positive or negative. Positive reinforcer. Increases the probability that an operant will occur when it is applied, or it increases the likelihood that a particular response will occur.When Claire gets praised whenever she responds in a quiet manner if her wishes were not granted immediately, she is likely to consistently follow this rewarded behavior. This is an example of positive reinforcement. Negative reinforcer. Increases the probability that an operant will occur when it is removed. People often learn to plan ahead so that they n eed not fear that things will go wrong. Fear acts as a negative reinforcer, because removal of fear increases the probability that the behaviors preceding it will be repeated (Rathus, 1990).Putting the Behavioral Program in Motion: Since it is predictable that Claire will put on a tantrum anytime of the day for whatever it may fancy her, the parents must know or be knowledgeable about why it happens. The parents must be thoroughly acquainted with the notion of operant conditioning. Claire obviously has learned in a number of events that whenever she puts on a tantrum her parents cannot help but react according to her wishes instead of according to theirs. They must understand that, 1) Claire’s behavior (e. g.tantrums) will not be changed in an instant or overnight, if that’s to be realistic; 2) that they will probably be tempted to succumb for fear of the unknown or fear of what might happen to their daughter; 3) that they should not give in to their fears or to anger or frustration when the child will not learn immediately. When Claire goes into fits (which is usually the behavioral manifestation of a child in tantrums) like when she demands to have something that should not be hers, both parents must agree never to give in and instead, to leave where the event is happening.If it is happening inside the house, they must leave the area out of sight of the child but close enough to know what’s happening with her but never without her knowing. This must be done repeatedly until she learns to adapt; if inside a store or in a public area, either parent must anticipate these scenarios to happen and must come up with a variety of diversions. Both must be skillful enough that their diversion tactic must not be another venue or channel for Claire to use her manipulative abilities.The goal then is to make her know eventually that the child is not in command. The real goal is that parents must be the one in control in a firm manner and the child mus t come to accept her parents’ superior ability and that her good is their ultimate concern. Measuring the Success of the Behavioral Program The strength of an operant response can be measured by its resistance to extinction; that is, by how long it takes for the behavior to return to its original rate once the pleasant consequent consequence following the behavior no longer occurs.It is thus told that it is generally correct that for an operant response to be strengthened, the response should be rewarded. But reward in ordinary language denotes things such as money, candy, or praise. There would be times, however, that a reward will not always strengthen an operant response. Suppose, in this instance with Claire, that one of the parents or both parents would give Claire a candy or chocolate but if the problem is to withhold food such as these from her then it will be another dilemma that the parents are getting into.Hence, psychologists prefer to speak of reinforcement/s rath er than reward. The withdrawal of a negative reinforcer will also increase the likelihood of a particular behavior. It is clear that it is possible to increase the occurrence of the desired response by presenting or withdrawing a positive or a negative reinforcer, respectively. Note that positive and negative reinforcers do not connote â€Å"good† or â€Å"bad. † Psychologists neither call a positive reinforcer â€Å"good† reinforcer, nor a negative reinforcer a â€Å"bad† reinforcer.To eliminate tantrums then, the parents withhold the reinforcer (the attention), the tantrums should extinguish eventually if the parents can hold long enough. Measuring then the success of the program is through the length of time Claire spends in crying from the first time attention was withheld (probably from an hour to 45 minutes the next time it happens); then the second time; the third time and so on and this can be usually noticeable within only one week or seven days. Reference: Allen, K. E. , & Harris, F. R. (1966).Elimination of a child's excessive scratching by training the mother in reinforcement procedures. Behaviour Research and Therapy, 4, 79-84. Atkinson, R. L. , R. C. Atkinson, E. E. Smith, D. J. Bem, and S, Nolen-Hoeksema. 1993. Introduction to psychology. 13th Ed. New York: Harcourt College Publishers. Collier, G. (1969). Body weight loss as a measure of motivation in hunger and thirst. Annals of the New York Academy of Science, 157, 594-609. Rathus, S. A. 1990. Understanding child development. New York; Holt, Rinehart, and Winston.

Lavender.The Side Effects of Using Lavender Essay

Lavender Introduction Therapeutic Use:   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   For quite a long time, lavender has been used as an antiseptic and for mental health purposes. In the recent world, lavender is used as a traditional medication for ailments like anxiety, insomnia,restlessness, headache,depression, upset stomach, hair  loss among many others defects within the body of the human beings.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   In most cases, Lavender is always used as anaromatherapy. This is a condition in which the scent of the essential oil from the flower is inhaled. Apart from inhaling the essential oil, it can also be diluted with another oil then it is applied to the skin. The dried lavender flowers are at times used to prepare tea. Theliquid extracts can then be taken through themouth (Blumenthal, Goldberg & Brinckman, 2000). The Side Effects of Using Lavender   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The use of the diluted lavender oil or simply using lavender as an aromatherapy is in most cases considered safe for most adults. The disadvantage of this however is that applying lavender oil to the skin can at times cause irritation. Some reports have also been recorded that use of lavender can also cause the boys to develop breasts.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Lavender oil is poisonous when taken through the mouth.When the tea made from its extracts are taken by mouth, they can cause headache, constipation as well aschanges in appetite   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Using lavender as a sedative medicine may lead to increase in  drowsiness. Scientific Evidence That Show Efficacy for Any of the Therapeutic Uses   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   There is very little scientific proof to show lavender’s effectiveness in tackling health related issues.Several studies done on lavender for anxiety show different results that cannot be relied upon. Preliminary results of the study shows thatlavender oil when mixed with oils from other herbs, may help reduce hair loss. This condition is known asAlopecia  areata(Henly, Lipson & Korach, 2007). References Henley D.V, Lipson N, Korach K.S (2007). Prepubertal gynecomastia linked to lavender and tea tree oils.New England Journal of Medicine.  356(5), 479–485. Lavender. (2009). Natural Medicines Comprehensive Database. Retrieved from http www.naturaldatabase.comLavender (Lavandula angustifolia) Miller. (2009). Natural Standard Database. Retrieved from http://www.naturalstandard.com. Blumenthal M, Goldberg A. & Brinckman J. (2000). Lavender flower. In:Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Lippincott Williams & Wilkins. Source document

The Indian Art Expressed in the Form of Myths and Development of Buddhist Art Free Essay Example, 1500 words

Ancient Indian art is religious in nature. Most of the murals, paintings, and sculptures convey a sense of religious study and invoke the gods and goddesses in their various forms. Ancient Indian literature is also religious in nature though there are points of divergence between Indian art and literature. As Basham (1954) points out, Indian literature was the product of men and women who lived ascetically and were in self-denial having given up worldly pleasures whereas Indian art was the product of artisans and secular craftsmen . The latter though they worked under the guidance of priests and followed their instructions, loved the world with an intensity that reflected in the art forms that they were making. The spirit of Indian art had much to do with the times that the artworks were made and they are as much a reflection of the ebb and tide of history as they are of the reigning deities of the time. Further, the art reflected the conceptions of beauty that the artisans and peo ple felt for the inner truth that they were expressing. We will write a custom essay sample on The Indian Art Expressed in the Form of Myths and Development of Buddhist Art or any topic specifically for you Only $17.96 $11.86/page In the next section, we look at Buddhist Art and discuss the same. The development of Buddhist art is marked by a series of phases which were characterized by evolution from happy fleshy figures with little spirituality about them, but later they developed in grace and religious feeling (Brown, 1949).