# Patent

## Title
System and method for parallel multiplexing between servers in a cluster

## Abstract

Systems and methods are provided for providing parallel muxing between servers in a cluster. One such system can include a cluster of one or more high performance computing systems, each including one or more processors and a high performance memory. The cluster communicates over an InfiniBand network. The system can also include a middleware environment, executing on the cluster, that includes one or more application server instances. The system can further include a plurality of muxers, wherein each application server instance includes at least one muxer. Each muxer can receive information from a plurality of threads to transmit to a different muxer on a different application server instance over the Infiniband network using a plurality of parallel channels.

## Background
CLAIM OF PRIORITY
This application is a continuation of U.S. patent application Ser. No. 13/109,871, entitled “SYSTEM AND METHOD FOR PARALLEL MULTIPLEXING BETWEEN SERVERS IN A CLUSTER”, filed on May 17, 2011, which is now U.S. Pat. No. 8,756,329, issued on Jun. 17, 2014, which claims the benefit of priority to U.S. Provisional Patent Application titled “MIDDLEWARE MACHINE PLATFORM”, Application No. 61/383,285, filed Sep. 15, 2010; and U.S. Provisional Patent Application titled “MIDDLEWARE MACHINE PLATFORM”, Application No. 61/384,227, filed Sep. 17, 2010; each of which above applications is herein incorporated by reference.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. patent application Ser. No. 13/109,849, entitled “SYSTEM AND METHOD FOR ZERO BUFFER COPYING IN A MIDDLEWARE ENVIRONMENT”, filed May 17, 2011, which is now U.S. Pat. No. 8,856,460, issued Oct. 7, 2014; U.S. patent application Ser. No. 13/170,490, entitled “SYSTEM AND METHOD FOR PROVIDING SCATTER/GATHER DATA PROCESSING IN A MIDDLEWARE ENVIRONMENT”, filed Jun. 28, 2011; and U.S. patent application Ser. No. 13/167,636, entitled “SYSTEM AND METHOD FOR SUPPORTING LAZY DESERIALIZATION OF SESSION INFORMATION IN A SERVER CLUSTER”, filed Jun. 23, 2011; each of which above applications is herein incorporated by reference.


COPYRIGHT NOTICE
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF INVENTION
The present invention is generally related to computer systems and software such as middleware, and is particularly related to systems and methods for parallel multiplexing (herein referred to as muxing) between servers in a cluster.
BACKGROUND
Within any large organization, over the span of many years the organization often finds itself with a sprawling IT infrastructure that encompasses a variety of different computer hardware, operating-systems, and application software. Although each individual component of such infrastructure might itself be well-engineered and well-maintained, when attempts are made to interconnect such components, or to share common resources, it is often a difficult administration task. In recent years, organizations have turned their attention to technologies such as virtualization and centralized storage, and even more recently cloud computing, which can provide the basis for a shared infrastructure. However, there are few all-in-one platforms that are particularly suited for use in such environments. These are the general areas that embodiments of the invention are intended to address.
SUMMARY
Systems and methods are provided for providing parallel muxing between servers in a cluster. One such system can include a cluster of one or more high performance computing systems, each including one or more processors and a high performance memory. The cluster communicates over an InfiniBand network. The system can also include a middleware environment, executing on the cluster, that includes one or more application server instances. The system can further include a plurality of multiplexers (herein referred to as a muxer), wherein each application server instance includes at least one muxer. Each muxer can receive information from a plurality of threads to transmit to a different muxer on a different application server instance over the Infiniband network using a plurality of parallel channels.



BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows an illustration of a middleware machine environment, in accordance with an embodiment.
FIG. 2 shows another illustration of a middleware machine platform or environment, in accordance with an embodiment.
FIG. 3 shows a system that utilizes a single connection between servers, in accordance with an embodiment.
FIG. 4 shows a system that utilizes parallel connections between servers, in accordance with an embodiment.
FIG. 5 shows a flowchart of a method for providing parallel muxing between servers in a cluster, in accordance with an embodiment.



DETAILED DESCRIPTION
In the following description, the invention will be illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. References to various embodiments in this disclosure are not necessarily to the same embodiment, and such references mean at least one. While specific implementations are discussed, it is understood that this is done for illustrative purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without departing from the scope and spirit of the invention.
Furthermore, in certain instances, numerous specific details will be set forth to provide a thorough description of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in as much detail so as not to obscure the invention.
As described above, in recent years, organizations have turned their attention to technologies such as virtualization and centralized storage, and even more recently cloud computing, which can provide the basis for a shared infrastructure. However, there are few all-in-one platforms that are particularly suited for use in such environments. Described herein is a system and method for providing a middleware machine or similar platform (referred to herein in some implementations as “Exalogic”), which comprises a combination of high performance hardware, together with an application server or middleware environment, and additional features, to provide a complete Java EE application server complex which includes a massively parallel in-memory grid, can be provisioned quickly, and can scale on demand.
In particular, as described herein, systems and methods are provided for providing parallel muxing between servers in a cluster. One such system can include a cluster of one or more high performance computing systems, each including one or more processors and a high performance memory. The cluster communicates over an InfiniBand network. The system can also include a middleware environment, executing on the cluster, that includes one or more application server instances. The system can further include a plurality of muxers, wherein each application server instance includes at least one muxer. Each muxer can receive information from a plurality of threads to transmit to a different muxer on a different application server instance over the Infiniband network using a plurality of parallel channels.
FIG. 1 shows an illustration of a middleware machine environment 100, in accordance with an embodiment. As shown in FIG. 1, each middleware machine system 102 includes several middleware machine rack components 104, each of which includes a combination of high-performance middleware machine hardware nodes 106 (e.g., 64-bit processors, high performance large memory, and redundant InfiniBand and Ethernet networking), and a middleware machine software environment 108. The result is a complete application server environment which can be provisioned in minutes rather than days or months, and which can scale on demand. In accordance with an embodiment, each middleware machine system can be deployed as a full, half, or quarter rack, or other configuration of rack components, and several middleware machine systems can be coupled together, again using InfiniBand, to create larger environments. Each middleware machine software environment can be provisioned with several application server or other software instances, for example as shown in FIG. 1, an application server instance 109 could comprise a virtual machine 116, operating system 120, virtualization layer 124, and application server layer 128 (e.g. WebLogic, including servlet 132, EJB 134, and Gridlink 136 containers); while another application server instance 110 could comprise a virtual machine 116, operating system 120, virtualization layer 124, and data grid layer 140 (e.g. Coherence, including an active cache 142). Each of the instances can communicate with one another, and with both its middleware machine hardware node, and other nodes, using a middleware machine integration component 150, such as an ExaLogic integration pack, which itself provides several optimization features, such as support for InfiniBand and other features, as described in further detail below.
FIG. 2 shows another illustration of a middleware machine platform or environment, in accordance with an embodiment. As shown in FIG. 2, each application server instance can act as a sender and/or receiver 160, 161 within the middleware machine environment. Each application server instance is also associated with a muxer 162, 163, that allows application servers to communicate with one another via an InfiniBand network 164. In the example shown in FIG. 2, an application server instance can include a kernel space 162, user space 164, and application server (e.g. WebLogic space) 166, which in turn can includes a sockets direct protocol 168, JVM (e.g. JRockit/Hotspot layer) 170, WLS core 172, servlet container 174, and JSP compiler 176. In accordance with other examples, other combinations of middleware-type software can be included. In accordance with various embodiments, the machine integration component can provide features such as Zero Buffer Copies, Scatter/Gather I/O, T3 Connections, Lazy Deserialization, and GridLink DataSource, to provide the basis for, and improve performance within, the shared infrastructure.
T3 Connections (Parallel Muxing)
FIG. 3 shows a system that utilizes a single connection between servers, in accordance with an embodiment. As illustrated in FIG. 3, in a typical clustered scenario, a single connection 300 is effected between servers 302 and 304. For example, communications from server 302 are sent to a single muxer 306, where they are transmitted to server 304 over the single connection 300. A corresponding single muxer 308 at server 304 then forwards the communications to their appropriate destinations. However, this single connection is unable to fully utilize bandwidth available in an InfiniBand (IB) network.
FIG. 4 shows a system that utilizes parallel connections between servers, in accordance with an embodiment. As shown in FIG. 4, a plurality of parallel connections 310 can be maintained between servers 312 and 314. Each server includes a parallel muxer, 316 and 318, to send communications in parallel over the plurality of connections between the servers. In accordance with an embodiment, the T3, or similar, protocol can be modified to allow multiple connections, which avoids per-connection bottlenecks, and allows better utilization of network bandwidth for features such as in-memory session replication. This enables the available IB bandwidth to be better utilized and provides more efficient communications, with fewer slowdowns, between peers.
As described above, in accordance with an embodiment the platform supports the Internet Protocol over INFINIBAND (IPoIB) network in its backplane, wherein the network bandwidth of IB is 25 Gbps. Since a single connection, such as the T3 in Weblogic Server, is unable to fully utilize IB bandwidth for cluster communication, multiple connections have been created in parallel to better utilize network bandwidth. Multiple connections help in spreading out the session replication network traffic.
In accordance with an embodiment, a server, for example a WebLogic server using the T3 protocol, can aggregate messages from all threads into a single sender queue which is flushed over the network by a single thread. Lock contention can occur when multiple processes require the same lock to proceed, for example lock contention can occur between threads attempting to add messages into the sender queue. By creating multiple connections in parallel, lock contention is distributed over multiple connections, thus reducing the per connection lock contention. Also, there are multiple sender threads sending messages over to a remote server instance causing parallelization of work flow.
In accordance with an embodiment, implicit replication channels can be created by using the replication channel configured on a ClusterMBean as a template. The number of implicit channels created is based on the ServerMBean.getReplicationPorts ( ) attribute. The implicit channels copy over all the attributes from the ClusterMBean.ReplicationChannels while overriding the port information to keep it unique. The overriding port information is obtained from ServerMBean.getReplicationPorts ( ). Additionally, the system can include a utility function which can be used to determine if multiple channels are configured. The utility can make the determination once, automatically at regular intervals, in response to changes to the configuration, and/or at the direction of a user and cache the result for subsequent calls. The system can further create an exclusive Remote Method Invocation (RMI) stub for each replication channel configured (stub assigned for each connection). The system can hash the session ID to balance the replication request amongst all the stubs, for example by using round-robin or other similar balancing algorithm. The system can also ensure that replication calls are received on one of the replication channels configured for the server.
In accordance with an embodiment, using InfiniBand provides more bandwidth than prior systems which, effectively, provides a larger pipe through which data can be transmitted. To better utilize the larger pipe, multiple parallel logical connections, i.e., channels, can be used instead of a single logical connection. Multiple connections mean more concurrent activity can execute without the various executing threads blocking each other. This can be useful, for example for clustering; that is, where multiple servers are communicating with each other in a cluster. In a cluster, session data replication between servers is an important feature. Session data can include, for example, shopping cart or other user data that is specific to a particular visit, or session, to a website. By using multiple connections between servers in the cluster, in-memory session replication to each server can be effected more reliably and more efficiently. This preserves session data in case of server failure and improves the experience of the end user and the service provider.
FIG. 5 shows a flowchart of a method for providing parallel muxing between servers in a cluster, in accordance with an embodiment. At step 400, a cluster of one or more high performance computing systems is provided. Each of the high performance computing systems can include one or more processors and a high performance memory. Additionally, the cluster can communicate over an InfiniBand network. At step 402, a middleware environment, which executes on the cluster, is provided. The middleware environment can include one or more application server instances. At step 404, a plurality of muxers are provided. Each application server instance can include at least one muxer. At step 406, a first muxer, at a first application server instance, receives information from a plurality of threads to transmit to a second muxer at a second application server instance. At step 408, the information is transmitted to the second muxer over the Infiniband network using a plurality of parallel channels.
In accordance with an embodiment, the method shown in FIG. 4 can also include configuring how many parallel channels are included in the plurality of parallel channels, based on input from a user. Additionally, the information transmitted can include session data. Furthermore, each multiplexer (herein referred to as a muxer) can be a New I/O (NIO) muxer. The method shown in FIG. 4 can further include creating an RMI stub for each of the plurality of parallel channels.
The present invention can be conveniently implemented using one or more conventional general purpose or specialized digital computer, computing device, machine, or microprocessor, including one or more processors, memory and/or non-transitory computer readable storage media programmed according to the teachings of the present disclosure. Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software art.
In some embodiments, the present invention includes a computer program product which is a computer readable storage medium (media) having instructions stored thereon/in which can be used to program a computer to perform any of the processes of the present invention. The computer readable storage medium can include, but is not limited to, any type of disk including floppy disks, optical discs, DVD, CD-ROMs, microdrive, and magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic or optical cards, nanosystems (including molecular memory ICs), or any type of media or device suitable for storing instructions and/or data.
The foregoing description of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will be apparent to the practitioner skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications that are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalence.

## Claims

1. A system for providing parallel multiplexing between servers in a cluster, comprising:
a cluster of one or more computing systems, each including one or more processors, wherein the cluster communicates over a network;
a middleware environment, executing on the cluster, that includes a first application server instance, and a second application server instance, each application server instance including a multiplexer;
a plurality of parallel channels created for data replication from the first application server instance to the second application server instance, the plurality of parallel channels directly connected to the multiplexer on each application server instance, wherein each parallel channel is created based on a replication channel template configured on a management bean of the cluster, and wherein the number of the parallel channels is determined by an attribute of a server management bean; and
wherein the multiplexer on the first application server instance operates to replicate data from the first application server instance to the second application server instance concurrently over the plurality of parallel channels.

2. The system of claim 1, further comprising
a utility function used to determine if the plurality of parallel channels has been configured, wherein the determination is made once, or at a regular interval in response to changes in the configuration of the plurality of parallel channels.

3. The system of claim 2, wherein the utility function makes the determination automatically or at the direction of a user.

4. The system of claim 1, wherein each of the plurality of parallel channels includes unique port information obtained from the cluster management bean.

5. The system of claim 1, wherein the data replicated from the first application server instance to the second application server instance are session data.

6. The system of claim 1, wherein each said multiplexer is a New I/O (NIO) multiplexer.

7. The system of claim 1, wherein a plurality of attributes of the channel template is copied from the template, with port information in the plurality of attributes being overridden.

8. A method for providing parallel multiplexing between servers in a cluster, comprising:
providing a middleware environment, executing on a cluster of computing systems, each including a microprocessor, wherein the middleware environment includes a first application server instance, and a second application server instance, each application server instance including a multiplexer;
creating a plurality of parallel channels for data replication from the first to the second application server instance, the plurality of parallel channels directly connected to the multiplexer on each application server instance, wherein each parallel channel is created based on a replication channel template configured on a management bean of the cluster, and wherein the number of the parallel channels is determined by an attribute of a server management bean; and
replicating, via the multiplexer on the first application server instance, data from the first application server instance to the second application server instance concurrently over the plurality of parallel channels.

9. The method of claim 8, further comprising:
determining, via a utility function, if the plurality of parallel channels has been configured, wherein the determination is made once, or at a regular interval in response to changes in the configuration of the plurality of parallel channels.

10. The method of claim 9, wherein the utility function makes the determination automatically or at the direction of a user.

11. The method of claim 8, wherein each of the plurality of parallel channels includes unique port information obtained from the cluster management bean.

12. The method of claim 8, wherein the data replicated from the first application server instance to the second application server instance are session data.

13. The method of claim 8, wherein each said multiplexer is a New I/O (NIO) multiplexer.

14. The method of claim 8, wherein a plurality of attributes of the channel template is copied from the template, with port information in the plurality of attributes being overridden.

15. A non-transitory computer readable storage medium, including instructions stored there on which, when executed by a computer, cause the computer to perform the steps comprising:
providing a middleware environment, executing on a cluster of computing systems, each including a microprocessor, wherein the middleware environment includes a first application server instance, and a second application server instance, each application server instance including a multiplexer;
creating a plurality of parallel channels for data replication from the first to the second application server instance, the plurality of parallel channels directly connected to the multiplexer on each application server instance, wherein each parallel channel is created based on a replication channel template configured on a management bean of the cluster, and wherein the number of the parallel channels is determined by an attribute of a server management bean; and
replicating, via the multiplexer on the first application server instance, data from the first application server instance to the second application server instance concurrently over the plurality of parallel channels.

16. The non-transitory computer readable storage medium of claim 15, further comprising:
determining, via a utility function, if the plurality parallel channels has been configured, wherein the determination is made once, or at a regular interval in response to changes in the configuration of the plurality of parallel channels.

17. The non-transitory computer readable storage medium of claim 16, wherein the utility function makes the determination automatically or at the direction of a user.

18. The non-transitory computer readable storage medium of claim 15, wherein each of the plurality of parallel channels includes unique port information obtained from the cluster management bean.

19. The non-transitory computer readable storage medium of claim 15, wherein the data replicated from the first application server instance to the second application server instance are session data.

20. The non-transitory computer readable storage medium of claim 15, wherein each said multiplexer is a New I/O (NIO) multiplexer.