This page refers to the gLite version of CREAM. For CREAM released with EMI, please refer to the new CREAM wiki: http://wiki.italiangrid.org/CREAM
The CREAM (Computing Resource Execution And Management) Service is a simple, lightweight service that implements all the operations at the Computing Element (CE) level; its well-defined WebService-based interface and its implementation as an extension of the Java-Axis servlet (running inside the Apache Tomcat container) provide interoperability with clients written in any programming language and running on any computer platform.
The CREAM interface is well-defined using the Web Service Description Language (WSDL); anyone can generate his/her CREAM client by simply filling in the stub code generated by WSDL parser (gSOAP for C/C++, Axis for Java, Perl module for perl).
CREAM Main functionality:
- Job Submission
- Possibility of direct staging of input sandbox files
- GLITE WMS JDL compliance (with CREAM-specific extensions)
- Support for batch and MPI jobs
- Support for bulk jobs being integrated
- Manual and automatic proxy delegation
- Job Cancellation
- Job Info with configurable level of verbosity and filtering based on submission time and/or job status
- Job List
- Job Suspension and Resume
- GSI based authentication
- VOMS based authorization
- Job Purge for terminated jobs
- Possibility (for admin) to disable new submissions
CREAM can be used
- by the Workload Management System (WMS), via the ICE (Interface to CREAM Environment) service
- by a generic client, e.g. an end-user willing to directly submit jobs to a CREAM CE. A C++ command line interface and Java clients are available.
Thanks to ICE (a gSOAP/C++ intermediate layer) CREAM can receive job operations directly from a Grid WMS (Workload Management System). ICE basically has the role that the Job Controller (LC) + Log Monitor (LM) + CondorG play when dealing with non-CREAM CEs