摘要:
A method (and system) for detecting intrusions to stored data includes creating a point-time-copy of a logical unit, and comparing at least a portion of the point-time-copy with a previous copy of the logical unit. The method (and system) monitors access to a data storage system and detects an intrusion or any other intentional or unintentional, unwanted modification to data stored in the data storage system. The method (and system) also recovers data once an intrusion or other unwanted modification is detected.
摘要:
A translation table has entries that each include a share bit and a delta bit, with pointers that point to a memory block that includes reuse bits. When two translation table entries reference identical fragments in a memory block, one of the translation table entries is changed to refer to the same memory block referenced in the other translation table entry, which frees up a memory block. The share bit is set to indicate a translation table entry is sharing its memory block with another translation table entry. In addition, a translation table entry may include a private delta in the form of a pointer that references a memory fragment in the memory block that is not shared with other translation table entries. When a translation table has a private delta, its delta bit is set.
摘要:
A method and circuit for implementing a cache directory and efficient cache tag lookup in very large cache systems, and a design structure on which the subject circuit resides are provided. A tag cache includes a fast partial large (LX) cache directory maintained separately on chip apart from a main LX cache directory (LXDIR) stored off chip in dynamic random access memory (DRAM) with large cache data (LXDATA). The tag cache stores most frequently accessed LXDIR tags. The tag cache contains predefined information enabling access to LXDATA directly on tag cache hit with matching address and data present in the LX cache. Only on tag cache misses the LXDIR is accessed to reach LXDATA.
摘要:
A fanning route generation technique is provided for multi-path networks having a shared communications fabric. The technique includes selecting a source node—destination node (S-D) group having common starting and ending sets of links from the network of interconnected nodes. Within this group, selecting the shortest routes between the S-D nodes of the group so that: selected routes substantially uniformly fan out from the source node to a center of the network and fan in from the center of the network to the destination node, thereby achieving local balance; and global balance of routes passing through links that are at a same level of the network is achieved.
摘要:
A diagnostic system and method for repairing computing devices comprises a diagnostic application running on a same computing system having a failed operating system (O/S). The diagnostic application is provided with access to the file system of the failed O/S image. The diagnostic software application collects relevant configuration information from the file system of the failed O/S image, and transports this information to a proxy system running the same operating system as the computing device being diagnosed. The proxy system utilizes the collected data to diagnose the subject failed O/S system. Once the proxy makes a determination it synthesizes repair information comprising new or modified files and instructions to be transported back to the diagnostic software system to apply. A network connection is provided between the computer running the diagnostic application and the proxy system that enables data to be easily transported between the two systems without human intervention.
摘要:
In an apparatus having a network including successive stages of cross-point switches which collectively interconnect a plurality of nodes external to said network, wherein at least one message is carried between one of the nodes and one of the cross-point switches over a route through said network, a method for preventing routing deadlocks from occurring in the network which comprises the steps of: creating a graphical representation of the network; searching for the existence of cycles within the graphical representation; partitioning the graphical representation into at a first subgraph and a second subgraph if cycles exist in the graphical representation; searching for the existence of edges directed from the first subgraph to the second subgraph; and removing the edges directed from the first subgraph to the second subgraph. Preferably the step of partitioning the network into at a first subgraph and a second subgraph is performed such that the first subgraph and the second subgraph have an equal number of vertices, a number of directed edges from the first subgraph to the second subgraph is minimized so as to minimize the number of routes prohibited, and a set of partition constraints are satisfied. The method is recursively applied to the first subgraph and then the second subgraph, thereby removing all of the deadlock prone cycles in the network while minimizing the number of routes prohibited due to remove edges.
摘要:
A computer cache memory organization called Probabilistic Set Associative Cache (PAC) has the hardware complexity and latency of a direct-mapped cache but functions as a set-associative cache for a fraction of the time, thus yielding better than direct mapped cache hit rates. The organization is considered a (1+P)—way set associative cache, where the chosen parameter called Override Probability P determines the average associativity, for example, for P=0.1, effectively it operates as if a 1.1-way set associative cache.
摘要:
A hash table method and structure comprises a processor that receives a plurality of access requests for access to a storage device. The processor performs a plurality of hash processes on the access requests to generate a first number of addresses for each access request. Such addresses are within a full address range. Hash table banks are operatively connected to the processor. The hash table banks form the storage device. Each of the hash table banks has a plurality of input ports. Specifically, each of the hash table banks has less input ports than the first number of addresses for each access request. The processor provides the addresses to the hash table banks, and each of the hash table banks stores pointers corresponding to a different limited range of addresses within the full address range (each of the different limited range of addresses is less than the full address range).
摘要:
A computer cache memory organization called Probabilistic Set Associative Cache (PAC) has the hardware complexity and latency of a direct-mapped cache but functions as a set-associative cache for a fraction of the time, thus yielding better than direct mapped cache hit rates. The organization is considered a (1+P)—way set associative cache, where the chosen parameter called Override Probability P determines the average associativity, for example, for P=0.1, effectively it operates as if a 1.1-way set associative cache.
摘要:
A virtual machine (VM) is migrated from a physical source node to a physical destination node in an InfiniBand network. A virtual host channel adapter (VHCA) is allocated on the source node for the VM to be migrated. The VHCA is suspended and put into the inactive state. The state information of the VM, including VHCA state information, is saved in a location-transparent manner. The state information is transferred from the source node to the destination node. A new VM is created, and a VHCA is allocated for the new VM on the destination node. The state information is transferred from the source node, including the VHCA state information. The routing and switching information is updated, operation of the VM is resumed, and the VHCA is put into an active state.