Abstract: A method for data storage includes storing data in a memory including multiple analog memory cells arranged in blocks. A first subset of the blocks is defined for storing first data with a first storage density, and a second subset of the blocks is defined for storing second data with a second storage density, larger than the first storage density. In each of the first and second subsets, one or more blocks are allocated to serve as spare blocks and blocks that become faulty are replaced with the spare blocks. Upon detecting that a number of the spare blocks in the second subset has decreased below a predefined threshold, the data is copied from at least one block in the second subset to the first subset, and the at least one block is added to the spare blocks of the second subset.

Abstract: A method for operating a memory includes receiving memory access commands associated with respective target logical addresses, for execution in a memory. The target logical addresses are translated into respective intermediate logical addresses, in accordance with a first mapping having a first granularity of a first data unit size. The intermediate logical addresses are translated into respective physical storage locations in the memory, in accordance with a second mapping having a second granularity of a second data unit size, larger than the first data unit size. The memory access commands are executed in the memory in accordance with the respective physical storage locations.

Abstract: A method for data storage includes storing data in a memory including multiple analog memory cells arranged in blocks. A first subset of the blocks is defined for storing first data with a first storage density, and a second subset of the blocks is defined for storing second data with a second storage density, larger than the first storage density. In each of the first and second subsets, one or more blocks are allocated to serve as spare blocks and blocks that become faulty are replaced with the spare blocks. Upon detecting that a number of the spare blocks in the second subset has decreased below a predefined threshold, the data is copied from at least one block in the second subset to the first subset, and the at least one block is added to the spare blocks of the second subset.