International Business Machines Corporation

Other

Mark John Lorenc

Damian Leo Osisek

Kevin Scott Adams

Donald W Schmidt

Richard John Moore

Juergen F Trost

Daniel J Rastatter

David Mellor

John F Harris

A method for reducing virtual machine preemption in a virtualized environment is provided. The method includes dispatching a virtual central processing unit (CPU) to run in an emulation mode on a real CPU until the real CPU exits the emulation mode, determining whether the virtual CPU has loaded a wait state, determining whether a remaining time slice of the virtual CPU as a result of the dispatching is below a predefined threshold in an event that the virtual CPU has loaded the wait state and rescheduling the virtual CPU with a full time slice in an event the remaining time slice of the virtual CPU is below the predefined threshold.

Reducing virtual machine pre-emption in virtualized environment

Dynamic relocation of virtual machines among hypervisors in a domain is provided. A domain management module is executed on a computer processor and is configured to receive a request to add a new hypervisor to a domain. Each hypervisor and each domain comprises an architecture description (ARD). A new canonical ARD is generated for all hypervisors in the domain. A virtual machine executing on a first system is relocated to any other hypervisor in the domain. Virtual machines may also be moved to out-of-domain hypervisors through the use of override masks. In addition, under certain conditions, new hypervisors additions, as well as hypervisor and system updates may be performed without disrupting the virtual machines that are controlled by the hypervisors.

Dynamic virtual machine domain configuration and virtual machine relocation management

Managing locks under conditions wherein there is a first shared hold on a lock. There is a first pending request for a first exclusive hold on the lock; the first pending request for said first exclusive hold is made after the first shared hold was granted. There is a second pending request for a second exclusive hold on the lock; the second pending request for the second exclusive hold is made after the first pending request for the first exclusive hold. There is a third pending request for a second shared hold; the third pending request for the second shared hold is made after the second pending request for the second exclusive hold. First program instructions grant one of the pending requests for an exclusive hold in response to the first shared hold being released. Second program instructions grant the third pending request for the second shared hold in response to release of the exclusive hold previously granted in response to the one request for an exclusive hold. Third program instructions grant another of the requests for an exclusive hold in response to the second shared hold being released.

System, method and program for managing locks

A method and apparatus for automatically planing a flitch. The method of the invention comprises measuring the distance between the top and bottom surfaces of the flitch at a plurality of longitudinally spaced locations, calculating a planing operation of the flitch based upon the plurality of distance measurements; and then planing the flitch according to the calculation. In a preferred embodiment, the measurements are taken by a bank of photodetectors in combination with a computer (microprocessor). The calculation is done by the microprocessor. The apparatus of the invention comprises means for making a plurality of distance measurements between a first generally planar surface of the flitch and a second generally frustoconical surface of the flitch, means for calculating a planing operation for the flitch based upon the measurements, and, means for planing the flitch in accordance with the calculations a variety of different types of planing heads can be used to do the actual planing, and the invention is not limited to any particular type or number of planing heads. The invention is capable of cutting stepped grooves in the bottom surface of the flitch to enable more stable veneer slicing on rotary cutters.

Automatic flitch planer

A computer system allocates processor time to multiple users. A systems operator or other administrator specifies to the computer a share of processor time for each user. A particular user's CPU usage is limited to an absolute value in a 'dispatch driven' multiprocessing system through the use of a monitor built into an active wait routine. The mechanism used is a list of users whose CPU resource must be limited so that their consumption does not exceed the limit value. The limit list is active wait monitored to determine when a user should be removed from the list in a low load situation and thus deliver the maximum CPU usage to the user if it is available.

Growing community of inventors

Endwell, NY, United States of America

Mark John Lorenc