A virtually-indexed and virtually-tagged cache has E entries each holding a memory line at a physical memory line address (PMLA), a tag of a virtual memory line address (VMLA), and permissions of a memory page that encompasses the PMLA. A directory having E corresponding entries is physically arranged as R rows by C columns=E. Each directory entry holds a directory tag comprising hashes of corresponding portions of a page address portion of the VMLA whose tag is held in the corresponding cache entry. In response to a translation lookaside buffer management instruction (TLBMI), the microprocessor generates a target tag comprising hashes of corresponding portions of a TLBMI-specified page address. For each directory row, the microprocessor: for each directory entry of the row, compares the target and directory tags to generate a match indictor used to invalidate the corresponding cache entry.

A synchronization capability to synchronize updates to page tables by forcing updates in cached entries to be made visible in memory (i.e., in in-memory page table entries). A synchronization instruction is used that ensures after the instruction has completed that updates to the cached entries that occurred prior to the synchronization instruction are made visible in memory. Synchronization may be used to facilitate memory management operations, such as bulk operations used to change a large section of memory to read-only, operations to manage a free list of memory pages, and/or operations associated with terminating processes.

A comparand that includes a virtual address is received. Upon determining a match of the comparand to a burst entry tag, a candidate matching translation data unit is selected. The selecting is from a plurality of translation data units associated with the burst entry tag, and is based at least in part on at least one bit of the virtual address. Content of the candidate matching translation data unit is compared to at least a portion of the comparand. Upon a match, a hit is generated.

An electronic device includes remapping hardware, a processor, and a Northbridge IC. The remapping hardware converts a virtual address included in an unconverted DMA request into a physical address. The processor executes software to configure the remapping hardware. The Northbridge IC sends the physical address to the processor. When the software changes the configuration of the remapping hardware, the remapping hardware outputs a data draining request to the Northbridge IC. When the Northbridge IC receives the data draining request at a first time, the Northbridge IC suspends unconverted DMA requests after the first time until a second time, and outputs a first data draining response to the remapping hardware at the second time. The remapping hardware receives the first data draining response and notifies the processor that the data draining request has been completed.

An address translation cache (ATC) is configured to store translation entries indicating mapping information between a virtual address and a physical address of a memory device. The ATC includes a plurality flexible page group caches, a shared cache and a cache manager. Each flexible page group cache stores translation entries corresponding to a page size allocated to the flexible group cache. The shared cache stores, regardless of page sizes, translation entries that are not stored in the plurality of flexible page group caches. The cache manager allocates a page size to each flexible page group cache, manages cache page information on the page sizes allocated to the plurality of flexible page group caches, and controls the plurality of flexible page group caches and the shared cache based on the cache page information.

Interrupt messages are sent from an interrupt controller to respective processor cores and data synchronization is managed among the processor cores. Each processor core includes a pipeline that includes a plurality of stages through which instructions of a program are executed, where stored order information indicates whether a state of the pipeline is in-order or out-of-order; and circuitry for receiving interrupt messages from the interrupt controller and performing an interrupt action in response to a corresponding interrupt message after ensuring that the order information indicates that the state of the pipeline is in-order when each interrupt action is performed. Managing the data synchronization includes generating a first interrupt message at an issuing processor core in response to a synchronization related instruction executed at the issuing processor core; and receiving the first interrupt message at each receiving processor core in a set of one or more receiving processor cores.

Memory scanning methods and apparatus are disclosed. An example apparatus includes a walker to traverse a paging structure of an address translation system; a bit analyzer to determine whether a bit associated with an entry of the paging structure is indicative of the entry being recently accessed; an address identifier to, when the bit analyzer determines that the bit associated with the entry of the paging structure is indicative of the entry being recently accessed, determine an address associated with the entry; and an outputter to provide the determined address to a memory scanner.

An aspect includes include selective purging of entries from translation look-aside buffers (TLBs). A method includes building multiple logical systems in a computing environment, the multiple logical systems including at least two level-two guests. TLB entries are created in a TLB for the level-two guests by executing fetch and store instructions. A subset of the TLB entries is purged in response to a selective TLB purge instruction, the subset including TLB entries created for a first one of the level-two guests. Subsequent to the purging, verifying that the subset of the TLB entries were purged from the TLB, and determining whether a second one of the level-two guests is operational, the determining including executing at least one instruction that accesses a TLB entry of the second one of the level-two guests. Test results are generated based on the verifying and the determining. The test results are output.

In a multithreaded data processing system including a plurality of processor cores, storage-modifying requests, including a translation invalidation request of an initiating hardware thread, are received in a shared queue. The translation invalidation request is broadcast so that it is received and processed by the plurality of processor cores. In response to confirmation of the broadcast, the address translated by the translation entry is stored in a queue. Once the address is stored, the initiating processor core resumes dispatch of instructions within the initiating hardware thread. In response to a request from one of the plurality of processor cores, an effective address translated by a translation entry being invalidated is accessed in the queue. A synchronization request for the address is broadcast to ensure completion of processing of any translation invalidation request for the address.

A system may be provided comprising: a local primary memory; an interconnect; and a processor, the processor configured to cause, in response to a memory allocation request from an application, allocation of a region of an external primary memory included in a memory appliance, the external primary memory in the memory appliance accessible by the system over the interconnect with client-side memory access, wherein the client-side memory access is independent of a central processing unit of the memory appliance, wherein the external primary memory is memory that is external to the system and primary memory to the system, and wherein the processor is further configured to operate the local primary memory as a cache for data accessed in the external primary memory included in the memory appliance.