Esper adds HA, local cache and resiliency to CEP with EsperHA

EsperTech has released its first non open source product EsperHA.
EsperHA is an extension to Esper the leading open source ESP/CEP event processing engine for Java. It essentially adds key features to match common enterprise deployments requirements:
- continuous query results can be made resilient and recovered if a crash occurs
- they can deal with large data window with an overflow / page out to disk option (f.e. keep a 20 days moving average VWAP, or find causality between events over long periods of time - countless of use cases)
- can simply make EPL statement durable so that they are re instantiated upon recovery / restart


From the announcement there is much more to look at, and the fact that all this comes at no code change, with fine level statement-level and stream-level configuration means that one can scale up or down its Esper applications with minimal effort.
By contrast, Esper keeps everything in live memory which provides excellent throughput and low latency (see some figures here) but is 1/ bounded (few G or more likely 32G to 128G in real deployments) and 2/ is dropped upon shutdown / crash.
EsperHA ensures one can trade-off low latency, high throughput and full resiliency in one system.

This is an interesting crossroad for EsperTech as a company as it further strengthen its positioning and readiness for real world deployments, and nicely complements its so far professional open source / dual license model with a classic software vendor one.
There was already great evidence of Esper fit for purpose in real world situations, as OEM and actual deployments demonstrated so far, but having this HA / resiliency option will certainly reinforce this.

There is common FUD from classic / elephant vendors thrown at open source software - essentially saying that it is not enterprise ready, not operable, as it is made by a bunch of volunteers that don't care about production reliability. This seems EsperHA and EsperTech proof point how much of FUD are that kind of claims.

You can sign up for a free trial and gain access to the download, docs and samples here.