One of the key challenges related to the grid environment is to efficiently use the storage resources of compute nodes. Therefore, we have developed the ViSaGe solution which features VisageFS - a POSIX-compliant wide-area file system, VCCC - a distributed lock mechanism, and VRT - a storage virtualization layer. In this paper, we present the VisageFStranslucentdirectoryproperty which enables a dynamic, transparent and efficient use of local storage by means of hierarchical Posix consistencies. Nodes that access a translucent enabled shared-directory will see different contents according to the site or node-level POSIX consistency. Thereafter, one of the various reconciliation modes re-enables the grid-level POSIX consistency. Our "nevermind'' mode does it inconstanttime.

A great number of scientific applications that access to a large amount of data have emerged last few years. For example in high energy physics, the volume of data will be measured in petabytes in the next years. Grids seek to aggregate geographically distributed resources for the need of these applications. It results that scientists have to deal with many problems to manage available data over the grid. Since grid resources are interconnected by WAN, the main speculation is that data transfers over the grid are bounded by network latency and bandwidth. Here, we point out some storage device issues which in many cases invalidate this assumption. Implicitly, we give a new direction that will lead to a better utilization of available resources on a grid