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  • License
    Apache License 2.0
  • Created almost 10 years ago
  • Updated almost 2 years ago


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Repository Details

FlexyPool adds metrics and failover strategies to a given Connection Pool, allowing it to resize on demand.

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The FlexyPool library adds metrics and flexible strategies to a given Connection Pool, allowing it to resize on demand. This is very handy since most connection pools offer a limited set of dynamic configuration strategies.

Flexy Pool architecture


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  1. Installation Guide
  2. User Guide
  3. Developer Guide

In the Press

  1. The anatomy of Connection Pooling
  2. FlexyPool, reactive connection pooling
  3. Connection pool sizing with Flexy Pool
  4. The simple scalability equation
  5. How to monitor a Java EE DataSource
  6. How does FlexyPool support the Dropwizard Metrics package renaming
  7. How does FlexyPool support both Connection proxies and decorators
  8. Applying Queueing Theory to Dynamic Connection Pool Sizing with FlexyPool
  9. Java Performance Tuning - November 2016
  10. Brett Wooldridge Shows What it Takes to Write the Fastest Java Connection Pool
  11. FlexyPool 2 has been released

Who uses FlexyPool

ToroDB Stampede is a replication and mapping technology allowing you to mirror a MongoDB database in a SQL database.

ToroDB Stampede exposes multiple metrics using JMX, some of them are custom metrics and other are metrics offered by third party products like Flexy-pool.

Etuovi is the leading real estate portal in Finland.

New Etuovi.com has used FlexyPool in production since early 2014.
The library has proven to be reliable and allows our infrastructure to handle temporary spikes much better. We use it everywhere in our stack, ranging from our frontends to the backend services.
-- Antti Koivisto, Software Architect, Etuovi.com

Scentbird is a website that allows its subscribers to try hundreds of designer fragrances at very affordable prices.

We have tried FlexyPool in Scentbird, after one week of intensive testing we decided switch it to FlexyPool and HikariCP in production mode, and everything works very robust and fast, we so happy about that!
Thank you for this library.
-- Andrey Rebrov, CTO, Scentbird