[SPARK-20836][LAUNCHER] DRIVER_EXTRA_JAVA_OPTIONS is needed only when use…

[wujianping10043419]

…rDeployMode is 'client'. If userDeployMode is not 'client', the launcher shouldn't care about DRIVER_EXTRA_JAVA_OPTIONS, nor should it exit abnormally because DRIVER_EXTRA_JAVA_OPTIONS contains Xmx configuration.

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[AmplabJenkins]

Can one of the admins verify this patch?

[srowen]

Although this could be moved, probably, it's not really worth bothering. It isn't actually redundant. If you specify driver memory settings in non-client mode, that should also be an error. Please close this.

[wujianping10043419]

@srowen
The DRIVER_EXTRA_JAVA_OPTIONS is from a file. Maybe, Setting the parameter is an error. But Spark doesn't use it in non-client mode, nobody should pay for food who doesn't eat,so I think the code is not robust.

[srowen]

The check is truly trivial, and the check is not actually irrelevant to non-client mode.

[wujianping10043419]

@srowen But the check result in the abnormal exit, because an irrelevant parameters.

[srowen]

This check is still correct for cluster mode. You should set memory with --driver-memory.