Steve Loughran created HADOOP-15281: ---------------------------------------
Summary: Distcp to add no-rename copy option Key: HADOOP-15281 URL: https://issues.apache.org/jira/browse/HADOOP-15281 Project: Hadoop Common Issue Type: Improvement Components: tools/distcp Affects Versions: 3.0.0 Reporter: Steve Loughran Assignee: Steve Loughran Currently Distcp uploads a file by two strategies # append parts # copy to temp then rename option 2 executes the following swquence in {{promoteTmpToTarget}} {code} if ((fs.exists(target) && !fs.delete(target, false)) || (!fs.exists(target.getParent()) && !fs.mkdirs(target.getParent())) || !fs.rename(tmpTarget, target)) { throw new IOException("Failed to promote tmp-file:" + tmpTarget + " to: " + target); } {code} For any object store, that's a lot of HTTP requests; for S3A you are looking at 12+ requests and an O(data) copy call. This is not a good upload strategy for any store which manifests its output atomically at the end of the write(). Proposed: add a switch to write direct to the dest path. either a conf option or a CLI option -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: common-dev-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-dev-h...@hadoop.apache.org