Efficient graph partitioning algorithms for collaborative grid workflow developer environments

Collaborative editing systems allow a group of users to view and edit a shared item from geographically dispersed sites. Consistency maintenance in the face of concurrent accesses to shared entities is one of the core issues in the design of these systems. The paper introduces a lock based solution and three associated algorithms by which grid workflow developer environments can enable concurrent access to grid applications for multiple persons. The methods assure that collaborators cannot break the consistency criteria of workflows by introducing cycles or invalid edges to them. A formal analysis of the three algorithms is provided, focusing on the number of users that can simultaneously edit the same graph. Based on the findings an integrated algorithm is defined and it allows even more users to collaborate during workflow development