Block storage is a key foundation to most file systems. File sharing and file locking are important processes for sharing cloud data resources, and for eliminating race conditions. Efficient implementation can make a significant mark on your system's and applications' performance levels. In this article, we use an open source example -- cloud platform Eucalyptus and its storage component Walrus -- to demonstrate how to modify block storage to improve the file-sharing and -locking mechanisms. Learn how to install Eucalyptus so you can deliver a top-notch Infrastructure-as-a-Service platform.