摘要:
Techniques are described herein for an automatic discovery and validation analyzer that identifies factors that have a particular effect on members of a population in engaging in certain activities. A baseline set and a divergent set of members of the population are identified based on whether a member has experienced a significant change in magnitude of the particular effect during a particular period of time. Differences in behaviors of members of the baseline and divergent sets are then analyzed to identify a candidate factor that corresponds to exposure to an item. Such a candidate factor is then validated as to whether it is a cause of said significant change in magnitude of the particular effect experienced by the divergent set of members.
摘要:
One embodiment of the present invention provides a system that optimizes support vector machine (SVM) kernel parameters. During operation, the system assigns sets of kernel parameter values to each node in a multiprocessor system. Next, the system performs a cross-validation operation at each node in the multiprocessor system based on a data set. This cross-validation operation computes an error cost value reflecting the number of misclassifications that arise while classifying the data set using the assigned set of kernel parameter values. The system then communicates the computed error cost values between nodes in the multiprocessor system, and eliminates nodes with relatively high error cost values. Next, the system performs a cross-over operation in which kernel parameter values are exchanged between remaining nodes to produce new sets of kernel parameter values. This process is repeated until a global winning set of kernel parameter values emerges.
摘要:
A system that detects a change point in a time series of telemetry signals from a computer system. During operation, the system receives the time series of telemetry signals from the computer system. For each element in the time series, the system (1) inserts the element into a data structure which keeps track of the number of elements in the data structure that have a value greater than and that have a value less than the value of the inserted element; and (2) uses the information stored in the data structure to add a contribution by the inserted element to a trend statistic for the time series. The system then uses the trend statistic to select a hypothesis for the trend in the time series.
摘要:
A system that identifies processes with a memory leak in a computer system. During operation, the system periodically samples memory usage for processes running on the computer system. The system then ranks the processes by memory usage and selects a specified number of processes with highest memory usage based on the ranking. For each selected process, the system computes a first-order difference of memory usage by taking a difference between the memory usage at a current sampling time and the memory usage at an immediately preceding sampling time. The system then generates a memory-leak index based on the first-order difference and a preceding memory-leak index computed at the immediately preceding sampling time.
摘要:
One embodiment of the present invention provides a system that monitors system-calls to identify runaway processes within a computer system. First, the system monitors system-calls on the computer system during runtime, to generate a trace of system-calls made. Then, the system analyzes the trace to detect runaway processes.