Other

International Business Machines Corporation

Robert W Collins

Larry Wayne Loen

Roy L Hoffman

Frank G Soltis

Glen R Mitchell

James S Effle

William S Davidson

Peter M Wottreng

Steven Michael Dickes

Russell J Weinschenk

Carle J Larson

A breather for a motorcycle engine separates and traps oil droplets entrained with crankcase gases. The breather has a container with a removable lid, an inlet for crankcase gases and entrained oil droplets extending through the lid into the container, filter media within the container to trap entrained oil droplets in the crankcase gases in the container, and outlet ports in the lid allowing gases to escape from within the container.

Breather for a motorcycle engine

A recovery mechanism restarts jobs following correction of a system failure and automatically marks the jobs for interruption at a logical boundary. The logical boundary is above logical file updating functions such that logical files are in a known state when jobs reach the boundary. When a system failure is detected which has not yet resulted in lost data, an image of working memory, including hardware status is saved on nonvolatile storage. After the failure has been resolved, the system is initially loaded with operating programs (IPL) and working memory is reloaded from the nonvolatile storage. All jobs which were reloaded are marked for interrupt at a machine instruction boundary, and processing is started. After all jobs have reached the boundary, or a predetermined time has elapsed, processing is stopped and the system is re-IPLed. There are few system index recoveries to be performed, since most jobs reached a point where logical files were synchronized with corresponding data.

Job interrupt at predetermined boundary for enhanced recovery

An apparatus provides synchronization for page replacement control in a paged, virtual memory environment in which either the CPU or the I/O devices may pin and unpin pages to control their replacement by the paging supervisor. Pinning and unpinning of pages by the I/O devices occurs independently of pinning and unpinning performed by the CPU. Synchronization is achieved by means of a virtual address translation mechanism which is common to the CPU and the I/O devices. The virtual address translation mechanism includes a primary directory having entries for each page in main storage, with each entry containing a field in which the pinning and unpinning operations by the CPU and the I/O devices are registered. In particular, this field is a counter which is incremented when a page is pinned by either the CPU or an I/O device and decremented when a page is unpinned. Each page directory entry also includes a field for indicating that references to the page corresponding to a given page directory entry are invalid. When it is determined that a particular page is no longer in use and is eligible for replacement, the page directory entry is set to indicate that further references to the page are invalid. When an I/O device gives up a buffer page, that page is unpinned. Buffer pages newly acquired by the I/O device are pinned when they are acquired by the device and have become available in main storage.

Synchronizing mechanism for page replacement control

Growing community of inventors

Rochester, MN, United States of America

Robert W Collins