Abstract: Embodiments are directed to determining latency in an interactive application. In one scenario, a computer system generates an indication that an input has been triggered. This indication identifies the input. The computer system sends the indication to an interactive application that receives and accesses the indication. The computer system further receives an output from the interactive application that includes an indication of the input, and determines an amount of latency between the sending of the generated indication and the receiving of the interactive application output.

Abstract: Embodiments are directed to determining latency in an interactive application. In one scenario, a computer system generates an indication that an input has been triggered. This indication identifies the input. The computer system sends the indication to an interactive application that receives and accesses the indication. The computer system further receives an output from the interactive application that includes an indication of the input, and determines an amount of latency between the sending of the generated indication and the receiving of the interactive application output.

Abstract: Certain applications, especially legacy applications, try to write to areas of the system that require administrator privileges and hence fail to run successfully for users with lessened privileges. The disclosed system redirects certain file writes, i.e., globally impactful file writes to specific locations that require administrator privileges and would otherwise fail for others users, so as to allow the same file writes to succeed by redirecting them to happen in the context of the user, i.e., in a per-user virtualization location. In particular, virtualization only occurs when the application is actually going to write to the file, not just when file access is requested without an intention of writing to or otherwise actually altering the file. Following virtualization, applications are redirected to use the virtualized files. The system thus allows users to run applications that otherwise would not be enabled, and to maintain a higher level of security when doing so.

Abstract: Goal state indicators can be communicated from a fabric controller of a computer cluster to each of multiple compute instances in the computer cluster managed by the fabric controller. The goal state indicators can be formatted according to a structured protocol that defines multiple possible goal states. Additionally, status reports can be received from the compute instances. Each of the status reports can indicate a current state of one of the compute instances relative to a goal state previously indicated in a goal state indicator communicated to that one of the compute instances.

Abstract: Goal state indicators can be communicated from a fabric controller of a computer cluster to each of multiple compute instances in the computer cluster managed by the fabric controller. The goal state indicators can be formatted according to a structured protocol that defines multiple possible goal states. Additionally, status reports can be received from the compute instances. Each of the status reports can indicate a current state of one of the compute instances relative to a goal state previously indicated in a goal state indicator communicated to that one of the compute instances.

Abstract: Increased efficiency in booting a computer uses a process of logging physical-level disk access during a boot cycle for use in creating a boot plan for a subsequent boot. Processing the log from one or more previous boots removes unnecessary reads such as those associated with temporary files and then orders the remaining read accesses based on times of prior read accesses and and by physical location on the disk. Upon boot, data likely to be requested first orders the remaining read accesses based on times of prior read accesses and By taking advantage of disk head and platter characteristics, data is read in sweeps through the disk, reducing overall latency. Requests that are not in cache may be held if the data is already scheduled for retrieval.

Abstract: A method includes loading an optical media image representing the content of a physical optical media device from an optical media image source into random access memory (RAM) and emulating the physical optical media device using the optical media image. The optical media image is in an optical media format. A system includes an optical media image stored in random access memory (RAM), the optical media image being in an optical media format, and including operating system (OS) code executable by a microprocessor. A RAM disk program accesses the optical media image according to the optical media format.

Abstract: Increased efficiency in booting a computer uses a process of logging physical-level disk access during a boot cycle for use in creating a boot plan for a subsequent boot. Processing the log from one or more previous boots removes unnecessary reads such as those associated with temporary files and then orders the remaining read accesses based on times of prior read accesses and and by physical location on the disk. Upon boot, data likely to be requested first orders the remaining read accesses based on times of prior read accesses and By taking advantage of disk head and platter characteristics, data is read in sweeps through the disk, reducing overall latency. Requests that are not in cache may be held if the data is already scheduled for retrieval.

Abstract: Methods and systems for recognizing a client computer as a replacement for a previous client computer or as being new to a computer network. When a client computer is connected to a server in a computer network, the client computer sends its unique identifier to the server. The server compares the unique identifier against a list of known unique identifiers. If the server determines that the unique identifier is unknown, the client computer prompts the user to select one of a list of user options, which include, for example, a replacement computer option and a new computer option. If the user selects the replacement computer option, the user also identifies the previous computer that has been replaced. The server then replaces the previous computer's unique identifier with the replacement computer's unique identifier, and assigns the replacement computer to an appropriate server computer.

Abstract: Methods and systems for adjusting an operating system configuration according to changes in hardware components of a client computer. The adjusted operating system can boot on the client computer regardless of changes in the hardware configuration of the client computer since it was last connected to a network server. Before the operating system boots, a preliminary connection is established between the client computer and the server. During the preliminary connection, the system identifies hardware components that are new and that must be supported by the operating system for bootup to occur. In particular, the server sends information relating to the previous client hardware configuration to the client computer. The client computer compares its current hardware configuration to the previous hardware configuration information, thereby identifying its new hardware components. Information identifying the new hardware components is sent to the server.

Abstract: A remote boot process uses a secret to sign and/or seal the data necessary to remotely boot a client from a server on a network to ensure the integrity of the data. The secret is generated by the server and securely delivered to the client during the initial setup of the client. The secret contains a one-way encryption of the password for the client account on the server. Each side balances a signed message with a verify and a sealed message with an unseal. Subsequent transactions between the client and server are conducted using messages encrypted with a key generated by the server and securely delivered to the client in a message sealed using the secret. The secret can also be used in conjunction with an access data structure to prevent unauthorized users from accessing data stored on the server on behalf of the client or other users. In other aspects of the invention, the secret is replaced by a client private/public key pair.

Abstract: A method and system for scheduling the execution of a plurality of threads in a computer system to control the concurrency level. Operating system data structures, called "queue objects," control the number of threads that are concurrently active processing incoming requests to an application program, a server or other processor of requests. The queue objects keep track of how many threads are currently active, and ensure that the number of active threads is at or near a predetermined target level of concurrency. By ensuring that new threads are not added to the pool of active threads if the system is operating at or above the target level of concurrency, the queue objects minimize the number of superfluous context switches that the operating system must perform and thus increases system efficiency and throughput.

Abstract: A method is provided for use in a computer system, the method for performing callbacks to a first calling thread that has made an RPC to a second called thread comprising the steps of: creating at least one respective helper thread in the address space of the second called thread; and for each respective created helper thread, providing a respective thread-specific identifying mechanism for identifying the first calling thread.