141 results about "Dynamic memory management" patented technology

An architecture for a contactless smart card or payment device, where the smart card is intended for use in both commerce transaction payment and transit fare payment (or other venue access) environments. The payment device may function as both an electronic wallet for commerce transactions and as a transit system card, for access to and fare payment of transit services. Implementation of both functions may be achieved by use of a dynamic memory management system that permits data for both the payment and transit applications to be stored on the card, with the transit data and storage locations isolated from those used to store data intended for use in paying for commerce transactions. The transit application specific data may include access control data (keys, passwords, identification data) or data required for fare calculations (rates, historical data on system use), for example.

A first processor and a second processor are configured to communicate secure inter-processor communications (IPCs) with each other. The first processor effects secure IPCs and non-secure IPCs using a first memory management unit (MMU) to route the secure and non-secure IPCs via a memory system. The first MMU accesses a first page table stored in the memory system to route the secure IPCs and accesses a second page table stored in the memory system to route the non-secure IPCs. The second processor effects at least secure IPCs using a second MMU to route the secure IPCs via the memory system. The second MMU accesses the second page table to route the secure IPCs.

A number of improvements in network adapters that offload protocol processing from the host processor are provided. Specifically, mechanisms for handling memory management and optimization within a system utilizing an offload network adapter are provided. The memory management mechanism permits both buffered sending and receiving of data as well as zero-copy sending and receiving of data. In addition, the memory management mechanism permits grouping of DMA buffers that can be shared among specified connections based on any number of attributes. The memory management mechanism further permits partial send and receive buffer operation, delaying of DMA requests so that they may be communicated to the host system in bulk, and expedited transfer of data to the host system.

With better knowledge of the behavior of objects in a running application, it is possible to improve execution environment decisions that affect management of such objects. For example, if available, object lifetime statistics could be employed in decisions that affect how and where objects are placed, e.g., on allocation or during operation of automatic dynamic memory management facilities such as a garbage collector. Typically, instrumenting all objects to sample lifetimes or other characteristics would impose an impractical level of overhead. We present a technique for dynamic sampling of a subset of allocated objects that incurs low runtime overheads. Coupled with automatic memory management or collection facilities, this technique allows us to improve the efficiency of a collector by segregating objects, sampled and non-sampled alike, based on observed characteristics such as object lifetime. The sampling techniques facilitate tracking of many kinds of object information. For purposes of illustration, an exemplary implementation is described in which such sampling techniques are exploited to improve performance of generational garbage collectors.

A method, system, and program for dynamic memory management of unallocated memory in a logical partitioned data processing system. A logical partitioned data processing system typically includes multiple memory units, processors, I / O adapters, and other resources enabled for allocation to multiple logical partitions. A partition manager operating within the data processing system manages allocation of the resources to each logical partition. In particular, the partition manager manages allocation of a first portion of the multiple memory units to at least one logical partition. In addition, the partition manager manages a memory pool of unallocated memory from among the multiple memory units. Responsive to receiving a request for a memory loan from one of the allocated logical partitions, a second selection of memory units from the memory pool is loaned to the requesting logical partition. The partition manager, however, is enabled to reclaim the loaned selection of memory units from the requesting logical partition at any time.