HAProxy is a free, very fast and reliable solution offering high availability, load balancing, and proxying for TCP and HTTP-based applications. The web sites crawling under very high loads can make good use of this while needing persistence or Layer7 processing. Todays hardware need to support large number of connections. The fragile web servers are not exposed to the web while Its mode of operation is such that the its integration with the existing architectures is very easy.
The available forms are:
It has may features such as client-side keep-alive-The heavy pages load time can be reduced. TCP speedups-It helps to save a few packets to the TCP stack. response buffering supports even lower number of concurrent connections. The RDP protocol implements the server stickiness and user filtering.
The lower versions 1.3 and 1.2 are also available.
The HAProxy implements an event-driven, single-process model so that very high number of simultaneous connections can be supported , that too at very high speeds. As the memory limits, system scheduler limits, and lock contention limits Multi-process or multi-threaded models in the case of multi thousand connections, this model is superior. a finer resource and time management is available with the Event-driven models and as a result they do not face these problems. HAProxy has never ever crashed in a production environment.
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