Abstract: A bare metal resource includes a trusted portion and an untrusted portion. The trusted portion includes trusted hardware, an image repository, and a clearance manager. The clearance manager is executable during bootup of the bare metal resource to perform a clearance process on the untrusted portion, including deleting the BIOS in the untrusted portion and loading a trusted BIOS from the image repository on the untrusted hardware, to place the untrusted portion in a trusted state. The bare metal resource may be provisioned to a tenant of a cloud provider after being placed in the trusted state.

Abstract: A bare metal resource includes a trusted portion and an untrusted portion. The trusted portion includes trusted hardware, an image repository, and a clearance manager. The clearance manager is executable during bootup of the bare metal resource to perform a clearance process on the untrusted portion, including deleting the BIOS in the untrusted portion and loading a trusted BIOS from the image repository on the untrusted hardware, to place the untrusted portion in a trusted state. The bare metal resource may be provisioned to a tenant of a cloud provider after being placed in the trusted state.

Abstract: Techniques are described for updating a host operating system on a server while maintaining virtual machines running on the server. An updated host operating system is copied to the server. The currently active host operating system freezes the virtual machines but leaves them resident in RAM. The allocations and state for each virtual machine is copied to RAM or local storage. The active host operating system is shut down. Instead of issuing a command to reboot the server after it finishes shutting down, the active host operating system transfers execution to a loader. The loader reads the kernel of the updated host operating system into RAM along with an allocation map for the virtual machines and instructions to resume the virtual machines. The loader transfers execution to the updated host operating system entry point, and the updated host operating system loads the states of the virtual machines and resumes them.

Abstract: Techniques are described for updating a host operating system on a server while maintaining virtual machines running on the server. An updated host operating system is copied to the server. The currently active host operating system freezes the virtual machines but leaves them resident in RAM. The allocations and state for each virtual machine is copied to RAM or local storage. The active host operating system is shut down. Instead of issuing a command to reboot the server after it finishes shutting down, the active host operating system transfers execution to a loader. The loader reads the kernel of the updated host operating system into RAM along with an allocation map for the virtual machines and instructions to resume the virtual machines. The loader transfers execution to the updated host operating system entry point, and the updated host operating system loads the states of the virtual machines and resumes them.

Abstract: A framework and method are disclosed for providing/consuming data items. A memory structure is created within an address space allocated to a provider application. The memory structure stores performance counter data generated by the provider application. The counter provider application registers a counter provider and an associated performance counter memory structure via a set of application program interface methods. Thereafter, a counter provider consumer application, via additional application program interface methods, determines the identity of the performance counter provider, sets up a buffer to receive the counter data of the counter provider, and requests extraction of the counter data stored within the performance counter memory structure. The transfer of data from the provider application to the consumer application occurs through the system API.

Abstract: The subject disclosure pertains to systems and methods that facilitate prevention of hard disk drive failure. Sophisticated drives are likely to be capable of detecting many of the conditions that either cause or precede hard disk drive failure. Such information can be provided to a host operating system, analyzed and used to correct errors associated with the hard disk drive to reduce the probability of failure and/or damage of the hard disk drive. The host operating system can respond by taking corrective actions that alleviate or mitigate hostile conditions (e.g., excessive vibration, heat, humidity and the like) prior to disk failure.

Abstract: A framework and method are disclosed for carrying out request completion tracing across request identification boundaries. When a request traverses an identification boundary, an event identifies the old and new request identifications and stores this linking information in a trace event record. Thereafter, a consumer of records maintains track of request completion by incorporating the linking information to switch identifications used to track completion of the request across request identification boundaries encountered by the system while responding to the received request. A request trace event record consumer architecture with enhanced tracking capabilities based upon a specified state machine provides greater power when interpreting the trace records associated with completion of requests by a server system.

Abstract: Methods, systems, and computer program products for correlating trace events to facilitate analysis based on how the trace events are related. Relationship information that defines relationships between logical operations is maintained within a correlation identifier stack. A correlation identifier that marks the occurrence of a logical operation is obtained for executing software and stored in the correlation identifier stack. A trace event is generated that comprises both the correlation identifier stack and an initial event payload to describe the runtime behavior of the executing software. The trace event is stored to a trace log for subsequent analysis of the executing software based on the logical operation relationship information in the correlation identifier stack and the initial correlation identifier that marks the occurrence of the logical operation. Upon obtaining an indication that the logical operation has ended, the correlation identifier is removed from the correlation identifier stack.

Abstract: The subject disclosure pertains to systems and methods that facilitate prevention of hard disk drive failure. Sophisticated drives are likely to be capable of detecting many of the conditions that either cause or precede hard disk drive failure. Such information can be provided to a host operating system, analyzed and used to correct errors associated with the hard disk drive to reduce the probability of failure and/or damage of the hard disk drive. The host operating system can respond by taking corrective actions that alleviate or mitigate hostile conditions (e.g., excessive vibration, heat, humidity and the like) prior to disk failure.

Abstract: A method of tracing data on a network that detects receive and send events in a protocol stack is provided. The method provides key information for capacity planners for correctly charging network traffic to the individual services and applications. The TCP/IP stack is instrumented at the transport layer, so that Input/Output Request packets (IRP) representing sends and receives can be detected as they pass through the stack. When such packets are detected an appropriate send or receive event is recorded in a trace log.

Abstract: A method is provided for estimating the size of cache memory required for optimal performance of a network database service, such as a directory service, by means of an iterative process. In the estimation process, the memory size N for best-case performance (i.e., the memory size that avoids any disk I/O operation) is first determined. The allocated memory size is then given a starting value. The probability (p) of cache-miss is then estimated for that memory size. Another probability (q), which is the probability that a record requested by a frequent user of the service is not in the cache, is also estimated for the memory size. The performance impact of the disk I/O rate indicated by p and q is then evaluated. If the performance is not adequate, the cache memory size is adjusted to a different value. The miss probabilities p and q are again estimated, and the performance impact is estimated. This iterative process is continued until the cache memory size is found to provide adequate estimated performance.