I have taken a look at the code of mesos spark-ec2 and documentation of AWS. I think that maybe I found the answer.
In fact, there are two types AMI in AWS EBS backed AMI and instance store backed AMI. For EBS backed AMI, we can add instance store volume when we create the images(The details can be founded in http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/creating-an-ami-ebs.html <http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/creating-an-ami-ebs.html> ). And then by default when we launch an instance from this AMI, the default instance store volume will be formatted(ext3) and mounted at /media/ephemeral0... etc The images provided by mesos spark-ec2 is EBS backed AMI and it is already added instance store volume(I guess). However, it is modified the file etc/fstab to mount the ephemeral disks to /mnt...etc (But I don't know how they modify dynamically the file etc/fstab) At last, as described in slave-setup.sh, for r3*, ext4 has the best performance. Hence, they reformat the ephemeral disk to ext4 and mount it to /mnt...etc. Hope this could help someone else. -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/The-question-about-mount-ephemeral-disk-in-slave-setup-sh-tp15675p15704.html Sent from the Apache Spark User List mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org