Storage is managed in a shared electronic store (SES) by assigning storage classes (STCs) to each directory entry having a data item stored in SES. The assignments of directory entries and data elements to the respective STCs can be changed at any time by any CPC. Eventually, no free space remains in the SES cache, and then space for new directory entries and data items must be obtained by reclaiming space occupied by directory entries and associated unchanged data items. The reclaiming of SES space is controlled on a STC basis. Any specified STC may reclaim from itself or from another STC using reclaiming software/microcode in SES, which includes a reclaim vector, a reclaim counter, a queue, and reclaiming controls. The vector and counter have respective elements for all possible STCs to controls how a specified STC may reclaim space from any or all target STC. Any enabled target STC reclaims its space according to an LRU algorithm maintained by a queue for the STC. A CPC can issue a command to load different values in target STC elements in the SES vector for a specified STC to control how reclaiming is apportioned for the specified STC. In SES, associated target counter elements are loaded from its vector. Reclaiming is done automatically in SES upon each directory miss in the current target STC having a non-zero counter value, when no free space exists. The counter is decremented for each reclaimed directory entry until its count reaches zero, and then the counter element for the next non-zero target STC is used for reclaiming until it reaches zero. When all STC elements in the counter are zero for the specified STC, the counter elements are reloaded from the vector elements to repeat the reclaiming operation, as long as a repeat factor for the specified STC has not reached zero. The repeat factor is decremented each time the counters are loaded from the vector. When the counters and repeat factor have all reached zero, reclaiming is disabled for the specified STC.