What is scatter and gather in parallel computing?

Gather and scatter are two fundamental data-parallel operations, where a large number of data items are read (gathered) from or are written (scattered) to given locations. In this paper, we study these two operations on graphics processing units (GPUs).

What is scatter-gather used for?

Use a Scatter-Gather that broadcasts a message to multiple recipients and re-aggregates the responses back into a single message. The Scatter-Gather routes a request message to the a number of recipients. It then uses an Aggregator to collect the responses and distill them into a single response message.

What are scatter-gather operations?

Scatter/gather is used to do DMA data transfers of data that is written to noncontiguous areas of memory. A scatter/gather list is a list of vectors, each of which gives the location and length of one segment in the overall read or write request.

What is the difference between scatter and gather?

Scatter the numbers to all processes, giving each process an equal amount of numbers. Each process computes the average of their subset of the numbers. Gather all averages to the root process.

What is scatter in high performance computing?

3 Scatter. The communication collective operation “scatter” distributes data of one process in separate parts to all the processes (including itself) within the scope of a communicator. The communicator of size processes disseminates the data of the source process in size-equal partitions.

What is scatter gather in distributed system?

Like replicated and sharded systems, the scatter/gather pattern is a tree pattern with a root that distributes requests and leaves that process those requests. However, in contrast to replicated and sharded systems, with scatter/gather requests are simultaneously farmed out to all of the replicas in the system.

Why do we use scatter-gather in Mulesoft?

The Scatter-Gather component is a routing event processor that processes a Mule event through different parallel processing routes that contain different event processors. Each route receives a reference to the Mule event and executes a sequence of one or more event processors.

How do you use scatter-gather?

The Scatter-Gather component then combines the Mule events returned by each processing route into a new Mule event that is passed to the next event processor only after every route completes successfully….Scatter-Gather XML Reference.

Element Description
target The name of the target variable.

What is scatter gather in Linux?

Scatter/Gather I/O. Scatter/gather I/O is a method of input and output where a single system call writes to a vector of buffers from a single data stream, or, alternatively, reads into a vector of buffers from a single data stream.

What is the output of scatter gather?

Scatter-Gather processes messages in-parallel and the result is an aggregated response of the routes. To live up to its merits, Scatter-Gather needs more than one message processing route.

Is scatter-gather asynchronous?

Scatter-Gather is the conversational view of the asynchronous Scatter-Gather. Instead of using an asynchronous flow of messages, it engages with both the Requestor and the Providers in a Asynchronous Request-Response conversation.

How does scatter gather mechanism work?

The Scatter-Gather router sends a message for concurrent processing to all configured routes. The thread executing the flow that owns the router waits until all routes complete or time out. If there are no failures, Mule aggregates the results from each of the routes into a message collection (MessageCollection class).

How is parallelism used in multithreading and scatter gather?

Multi-threading (+Spark) Scatter-gather (+Cromwell) Compare and combine. 1. The concept of parallelism. Parallelism is a way to make a program finish faster by performing several operations in parallel, rather than sequentially ( i.e. waiting for each operation to finish before starting the next one).

What does parallel execution mean in scatter gather?

Parallel execution means that even if one or many routes fail, the rest of the assigned routes still execute. If one or more routes throws an exception, scatter-gather throws a CompositeRoutingException, which allows the application to retrieve information about both failed and successful routes.

What does gather scatter mean in vector processing?

For the I/O method, see Vectored I/O. For Register Gather-scatter, part of Vector processing, see permute instruction. Gather-scatter is a type of memory addressing that often arises when addressing vectors in sparse linear algebra operations.

How does scatter / gather I / O work in a network?

Network traffic streams may be split up as they arrive, with various buckets in memory. This is referred to as “Scatter/gather I/O.” In a way, this is the reverse of other applications. In other applications, scattered data is brought together in the processor.