Provided are techniques for allocating logical memory corresponding to a logical partition in a computing system; generating, a S/W PFT data structure corresponding to a first page of the logical memory, wherein the S/W PFT data structure comprises a field indicating that the corresponding first page of logical memory is a klock page; transmitting a request for a page of physical memory and the corresponding S/W PFT data structure to hypervisor, allocating physical memory corresponding to the request; and, in response to a pageout request, paging out available logical memory corresponding to the logical partition that does not indicate that the corresponding page is a klock page prior to paging out the first page.