[HTTPCORE-390] Lock-less connection pools

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.3.2
• Fix Version/s: 5.0-alpha4
• Component/s: HttpCore NIO
• Labels: concurrency performance
• Assignee: Oleg Kalnichevski
• Reporter: Stephane Routhiau
• Created: 10/Sep/14 14:38
• Updated: 20/Aug/17 14:32
• Resolved: 20/Aug/17 14:32

Description

AbstractNIOConnPool use a ReentrantLock for lease and release connection.
We have noticed important contention when we try to use hundreds of connexions to the same host, the lock is to vast.

I managed to rework a part of the code so there is no more use of a ReentrantLock, but use of ConcurrentHashMap and so on.

The unit tests are ok and the load tests we have made on the patch version are about 40 % faster under heavy load

Please find attached patch file againt http-nio 4.3.2 and the modified sources files of http-nio 4.3.2

Issue Links

• is duplicated by: HTTPCLIENT-1809 Thread contention in PoolingHttpClientConnectionManager
• links to: GitHub Pull Request #3