A Brief Comparison of Two topology management methods for Distributed Computing Environments (Chubby & P2P overlay)

Topology management methods for the two distributed computing environments (
Chubby &
P2P overlay
)

----
Adam

 

In a distributed computing environment, dynamic management of network topology is a basic function. For stable system operation, an efficient and stable topology management layer is required to provide nodes (or application layer instances) for the upper layer) status information, event broadcast, and other functions. To
Google
And
Amazon
(
Dynamo
The cloud computing system is represented by two different Topology Management Methods: centralized management and
P2P
Overlapping network mode. Where:

 

Centralized management:

To
Chubby
It provides
Chubby
Cluster (usually
5
Station or
7
Server nodes ),
Chubby
Use
Paxos
Algorithm to synchronize all statuses and events. When the master node fails,
Paxos
A new master node will be elected to provide services. Therefore, based on
Chubby
The reliability of the centralized management mode is caused
Chubby
Cluster and
Paxos
Algorithm guarantee. Because
Chubby
In a distributed environment, the "announcement board" mode is used to provide read and write interfaces to external entities. All application layer instances can use this "announcement board" to publish events, at the same time, the "announcement board" can also publish information to all nodes that have registered the event. For example, the node leaves and joins;
Chubby
The corresponding events are broadcast to all nodes that "care" about the event. All nodes in the Distributed Environment
Chubby
You can obtain all the real-time topology information and dynamic topology changes.

 

P2P

Overlapping Network Mode:

Amazon
Dynamo
Topology Management relies on
Dynamo
Overlapping network management implementation, all nodes in the Distributed Environment
Gossip
Protocol, etc., through
P2P
To form an overlapping network. The topology update events in the network can also be broadcast through the overlapping network.
P2P
There are many ways to manage the topology of overlapping networks.
P2P
Application.

 

In the distributed computing environment, both methods can better solve network topology management. In the actual system, the specific mode is better, which needs to be determined based on different scenarios. The author compares the two methods in the following aspects:

 

1,



Reliability

Chubby
Because it is a single point of function, the system depends on this
Chubby
"Single Point"; although
Chubby
Is in the form of a cluster (usually
5
Station, or
7
Nodes );

P2P overlay
It is a self-healing network with no spof and strong self-healing capability;

Chubby
Because the cluster mode is generally used
IDC
In the deployment mode, the reliability must be able to meet the requirements to a certain extent.
Google
The cloud computing center is also verified;

P2P overlay
When the network is too large, if
P2P overlay
Split multiple isolated islands, which must be addressed at the application layer.

 

2,



Efficiency

Chubby
In centralized management mode, node Dynamic Monitoring and broadcast speed is generally faster. However, as the number of nodes increases, node dynamics increase
Chubby
A certain amount of pressure is formed;

P2P overlay
Node dynamic messages. If you need to broadcast channels across the network, you need to have a transmission process that takes a relatively long time. However
IDC
In the deployment environment, the number of nodes is limited. Each overlapping network node can save node information across the network to speed up information transmission. In many application scenarios, node dynamic events do not need to be broadcast across the network.

 

3,



Function

Chubby
In addition to implementing the topology management function, as it is the most reliable subsystem by default in the entire environment, it can also be used as a small-scale reliable storage subsystem to provide reliable storage functions;
Chubby
In
IDC
Ideal applications can also be obtained in a dynamic environment of the level;

P2P overlay
Mainly responsible for topology management, not other functions

 

4

, Scale

Chubby
It is a cluster, so it is applicable to a large-scale distributed environment. Because it is an independent subsystem, it can provide topology management and Low-granularity locks for many cloud computing subsystems at the same time, small file storage service;

P2P overlay
Suitable for small-scale cloud computing environments.
P2P overlay
It is integrated in the topology management layer of a system. Generally, it does not exist as an independent sub-system and there are no additional deployment tasks. Therefore, it is suitable for applications with simple functions.