Abstract: A facility that for a multithreaded program executing on a root machine causes the threads of the program to be executed in a relative scheduling that produces an interesting result. The facility suspends execution of the program. The facility then tests a plurality of relative thread schedulings on one or more virtual machines and observes the result. Based upon the observed result the facility selects one of the tested relative thread schedulings. The facility then resumes execution of the program using the selected relative thread scheduling.

Abstract: A facility for supporting the analysis of a multithreaded program is described. For each of a number of threads of the multithreaded program, the facility identifies a semantically meaningful point in the execution of the thread. The facility interrupts the execution of each thread at the point identified for the thread.

Abstract: A facility that for a multithreaded program executing on a root machine causes the threads of the program to be executed in a relative scheduling that produces an interesting result. The facility suspends execution of the program. The facility then tests a plurality of relative thread schedulings on one or more virtual machines and observes the result. Based upon the observed result the facility selects one of the tested relative thread schedulings. The facility then resumes execution of the program using the selected relative thread scheduling.

Abstract: A facility for identifying functionally distinct memory access reorderings for a multithreaded program is described. The facility monitors execution of the program to detect, for each of one or more memory locations, an order in which the memory location was accessed by the threads of the program, each access being at least one of a read access and a write access. Among a number of possible memory access reorderings of a read access by a reading thread to a location and a write access by a writing thread to the same location where the write access preceded the read access, the facility identifies as functionally distinct memory access reorderings those possible memory access reorderings where the reading thread could have become newly aware of changed state of the writing thread as a result of the indicated read access.

Abstract: A mapping system tailors maps and directions for bicyclists. The mapping system stores map data including data about the suitability for biking along roads in a road network. A cost model, including a turn model, a hill model, and a penalty/bonus model is applied to the road network. The turn model models how long it takes to traverse an intersection. The hill model models a bicyclist's speed based on the road grade. The penalty/bonus model adjusts the calculated cost of a road segment under the turn model and hill model to take account of steep hills and other unfavorable or favorable conditions along the road segment for bicycling. The mapping system generates one or more routes between an origin and destination. The generated route that has the lowest adjusted cost is determined to be a recommended route. The mapping system formats maps and/or directions to display recommended routes.

Abstract: A facility for supporting the analysis of a multithreaded program is described. For each of a number of threads of the multithreaded program, the facility identifies a semantically meaningful point in the execution of the thread. The facility interrupts the execution of each thread at the point identified for the thread.