When doing a put or copyFromLocal via the HDFS commandline, it puts the file into a temporary file and then moves it into place. The "-d" option skips the temporary file and copies the file directly into place. On S3, this avoids an extra copy and can also avoid consistency issues. We should look into using the "-d" option across our tests. Our usages of the HDFS commandline generally don't require atomicity of this file copy, so using "-d" is unlikely to impact HDFS tests.