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WE are using HDP-2.5.0.0-1245 . Log reports parameters are not at their default value. Does HDP tune values at install time.

Explorer

We did not tune the following parameters. However they are not at the default value as per the log

dfs.datanode.du.reserved =

1073741824
log -

Value is less than the recommended default of 6813825536 (Reserved space in bytes per volume. Always leave this much space free for non dfs use)


dfs.datanode.max.transfer.threads =

1024 ...

HAWQ requires this property to be set to the recommended value of 40960 (Specifies the maximum number of threads to use for transferring data in and out of the datanode)


mapreduce.map.java.opts =

"=-Xmx410m" ..

Value is less than the recommended default of -Xmx3276m (Larger heap-size for child jvms of maps.)


mapreduce.map.memory.mb
mapreduce.reduce.java.opts
mapreduce.reduce.memory.mb
mapreduce.task.io.sort.mb
yarn.app.mapreduce.am.resource.mb
tez.am.resource.memory.mb
tez.runtime.io.sort.mb
tez.runtime.unordered.output.buffer.size-mb
tez.task.resource.memory.mb
hive.auto.convert.join.noconditionaltask.size
hive.tez.container.size
output.replace-datanode-on-failure

Value is less than the recommended default of 6813825536 (Reserved space in bytes per volume. Always leave this much space free for non dfs use) . Why was the setting not set to the default on install.

1 REPLY 1

Expert Contributor

This may be a case of configuration defaults not being in sync with recommendations for configuration defaults.

During the installation process your cluster will be assigned certain defaults to start. As you move through cluster setup, you'll have the opportunity to change those defaults to the recommended configuration defaults through dialogs that throw warnings and errors onto your screen - it sounds like your administrator may have moved past this step without editing default values to match recommendations.

Another possibility is that your administrator has changed configuration settings after cluster setup, but did not change dependencies of those settings based on recommendations.

In either case, you should be able to change these fields to their recommended values if they make sense in your environment and pass basic sanity checks.