HDDS-9449. Create pipeline consider datanode storage.

[z-bb]

What changes were proposed in this pull request?

Currently, for clusters with unbalanced, the storage of the dn machine needs to be considered when creating a new pipeline. should not select a dn with full storage, because exceptions such as the machine being filled up or writing failure may occur.

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-9449

[adoroszlai]

Thanks @z-bb for working on this.

I'm not sure this change is necessary. There is already a setting to reserve some disk space on Datanode for other usage. It can be configured as absolute space or percentage. I think setting reserved to 10% has the same effect as setting this new datanode storage rate limit to 90%.

ozone/hadoop-hdds/common/src/main/resources/ozone-default.xml

Lines 188 to 195 in 607122c

	<property>
	<name>hdds.datanode.dir.du.reserved.percent</name>
	<value/>
	<tag>OZONE, CONTAINER, STORAGE, MANAGEMENT</tag>
	<description>Percentage of volume that should be reserved. This space is left free for other usage.
	The value should be between 0-1. Such as 0.1 which means 10% of volume space will be reserved.
	</description>
	</property>

[errose28]

I agree with @adoroszlai. I think between reserving space on datanodes and using SCMContainerPlacementCapacity for the container placement algorithm we can get the desired result.

[z-bb]

I agree with @adoroszlai. I think between reserving space on datanodes and using SCMContainerPlacementCapacity for the container placement algorithm we can get the desired result.

okey, i will close this mr. thanks review