What is meaning of "Hadoop distribution"
Since Hadoop is an open source project, a number of vendors have developed their own distributions, adding new functionality or improving the code baseVendor distributions are, of course, designed to overcome issues with the open source edition and provide additional value to customers, with a focus on things such as:
Reliability: The vendors react faster when bugs are detected. They promptly deliver fixes and patches, which makes their solutions more stable.
Support: A variety of companies provide technical assistance, which makes it possible to adopt the platforms for mission-critical and enterprise-grade tasks.
Completeness: Very often Hadoop distributions are supplemented with other tools to address specific tasks.
Have a look at this top-hadoop-distributions article and this presentation for benchmarking analysis among top three Hadoop distributions.
Based on Distributions and Commercial Support, The following companies provide products that include Apache Hadoop, a derivative work thereof, commercial support, and/or tools and utilities related to Hadoop.
Some companies release or sell products that include the official Apache Hadoop release files, and/or their own and other useful tools. Other companies or organizations release products that include artifacts build from modified or extended versions of the Apache Hadoop source tree. Such derivative works are not supported by the Apache Team: all support issues must be directed to the suppliers themselves.