1Simple Introduction
It's not a novelty to use memory as the primary storage medium, and we have a lot of examples of main memory databases (IMDB or MMDB) around us. In the use of main memory. The In memory data grid,IMDG , is similar to IMDB , but they are completely different in architecture.
IMDG features can be summarized as follows:
? The data is distributed across multiple servers.
? Each server is active mode.
? The data model is generally object-oriented and non-relational.
? on the basis of need. Server is often increased or decreased.
In addition, theIMDG is different from the normal cache system.
Similarly, the cache system is similar to IMDG in main memory usage and horizontal scaling. However, the use and purpose of the two are completely different. The caching system is merely buffering read pressure. Persistent storage such as an RDBMS is a must. Scale as in the Arcus cache system. The architecture of IMDG , please refer to Part two.
In other words,IMDG stores the object itself in memory and guarantees extensibility. Common business and open source products such as the following:
? hazelcast
? Terracotta Enterprise Suite
? VMware Gemfire
? Oracle Coherence
? gigaspaces XAP Elastic Caching Edition
? IBM eXtreme Scale
? JBoss Infinispan
2Architecture
IMDG the two core issues that need to be overcome are: capacity constraints and reliability. Typically,IMDG is designed to overcome limits on memory capacity through horizontal scaling, while ensuring reliability through a replication system. A typical IMDG architecture, for example, is seen.
So. The difference between the cache system and the IMDG described earlier is very obvious.
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3features
In addition to providing a distributed implementation of various data structures. IMDG typically uses out-of-heap memory (off-heap, or elastic memory ) to reduce the pressure on garbage collection.
References
1 Introduction to in-memory Data grid:main Features
Memory data grid IMDG Simple Introduction