[YARN-9273] Flexing a component of YARN service does not work as documented when using relative number

• Type: Bug
• Status: Patch Available
• Priority: Minor
• Resolution: Unresolved
• Assignee: Masahiro Tanaka
• Reporter: Masahiro Tanaka
• Created: 02/Feb/19 02:57
• Updated: 28/Feb/19 16:58

Description

The documents says,
"Relative changes are also supported for the ${NUMBER_OF_CONTAINERS} in the flex command, such as +2 or -2." when you want to flex a component of a YARN service.

I expected that yarn app -flex sleeper-service -component sleeper +1 increments the number of container, but actually it sets the number of container to just one.

I guess ApiServiceClient#actionFlex treats flexing when executing the yarn app -flex, and it just uses Long.parseLong to convert the argument like +1, which doesn't care relative numbers.