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Andrew Wang commented on HDFS-11428: ------------------------------------ Good question, it's read-only except for startup and shutdown, though we might eventually be loading custom policies from NN metadata or configuration. Not clear how that's going to work yet. > Change setErasureCodingPolicy to take a required string EC policy name > ---------------------------------------------------------------------- > > Key: HDFS-11428 > URL: https://issues.apache.org/jira/browse/HDFS-11428 > Project: Hadoop HDFS > Issue Type: Improvement > Components: erasure-coding > Affects Versions: 3.0.0-alpha1 > Reporter: Andrew Wang > Assignee: Andrew Wang > Labels: hdfs-ec-3.0-must-do > Attachments: HDFS-11428.001.patch, HDFS-11428.002.patch, > HDFS-11428.003.patch > > > The current {{setErasureCodingPolicy}} API takes an optional {{ECPolicy}}. > This makes calling the API harder for clients, since they need to turn a > specified name into a policy, and the set of available EC policies is only > available on the NN. > You can see this awkwardness in the current EC cli set command: it first > fetches the list of EC policies, looks for the one specified by the user, > then calls set. This means we need to issue two RPCs for every set > (inefficient), and we need to do validation on the NN side anyway (extraneous > work). > Since we're phasing out the system default EC policy, it also makes sense to > make the policy a required parameter. -- This message was sent by Atlassian JIRA (v6.3.15#6346) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org