Control System Virtualization for the LHCb Online System

Vir­tu­al­iza­tion pro­vides many ben­e­fits such as more ef­fi­ciency in re­source uti­liza­tion, less power con­sump­tion, bet­ter man­age­ment by cen­tral­ized con­trol and higher avail­abil­ity. It can also save time for IT pro­jects by elim­i­nat­ing ded­i­cated hard­ware pro­cure­ment and pro­vid­ing stan­dard soft­ware con­fig­u­ra­tions. In view of this vir­tu­al­iza­tion is very at­trac­tive for mis­sion-crit­i­cal pro­jects like the ex­per­i­ment con­trol-sys­tem (ECS) of the large LHCb ex­per­i­ment at CERN. This paper de­scribes our im­ple­men­ta­tion of the con­trol sys­tem in­fra­struc­ture on a gen­eral pur­pose server-hard­ware based on Linux and the RHEV en­ter­prise clus­ter­ing plat­form. The paper de­scribes the meth­ods used , our ex­pe­ri­ences and the knowl­edge ac­quired in eval­u­at­ing the per­for­mance of the setup using test sys­tems, con­straints and lim­i­ta­tions we en­coun­tered. We com­pare these with pa­ra­me­ters mea­sured under typ­i­cal load con­di­tions in a real pro­duc­tion sys­tem. We also pre­sent the spe­cific mea­sures taken to guar­an­tee op­ti­mal per­for­mance for the SCADA sys­tem (WinCC OA), which is the back-bone of our con­trol sys­tem.