International Business Machines Corporation

Christopher J Arges

Michael Thomas Strosaker

Joel Howard Schopp

Nathan Fontenot

Mark Wayne VanderWiele

Jeffrey David George

Ryan Patrick Grimm

According to one embodiment of the present disclosure, an approach is provided in which a processor selects a page of data that is compressed by a first compression algorithm and stored in a memory block. The processor identifies a utilization amount of the compressed page of data and determines whether the utilization amount meets a utilization threshold. When the utilization amount fails to meet the utilization threshold, the processor uses a second compression algorithm to recompresses the page of data.

Multi-level memory compression

Each time a currently scheduled virtual machine (VM) accesses a hardware resource over a bus for the hardware resource via the currently scheduled VM running on a processor, a hardware component adjusts a bandwidth counter associated with usage of the bus for the hardware resource, without involvement of the currently scheduled VM or a hypervisor managing the currently scheduled VM. Responsive to the bandwidth counter reaching a threshold value, the hardware component issues an interrupt for handling by the hypervisor to maintain bandwidth quality-of-service (QoS) of bus bandwidth related to the hardware resource. Upon expiration of a regular time interval prior to the bandwidth counter reaching the threshold value, the hardware component resets the bandwidth counter to a predetermined value associated with the currently scheduled VM, without involvement of the currently scheduled VM or the hypervisor; the hardware component does not issue an interrupt. The hardware resource can be memory.

Maintaining hardware resource bandwidth quality-of-service via hardware counter

A computer implemented method for control access to a contested resource. When a lock acquisition request is received from a virtual machine, the partition management firmware determines whether the lock acquisition request is received within a preemption period of a time slice allocated to the virtual machine. If the lock acquisition request is received within the preemption period, the partition management firmware ends the time slice early, and performs a context switch.

Hardware-enabled lock mediation for controlling access to a contested resource

An apparatus and system for protecting memory of a virtual guest includes initializing a virtual guest on a host computing system. The host computing system includes a virtual machine manager that manages operation of the virtual guest. The virtual guest includes a distinct operating environment executing in a virtual operation platform provided by the virtual machine manager. The method includes receiving an allocation of run-time memory for the virtual guest, the allocation of run-time memory comprising a portion of run-time memory of the host computing system. The method includes setting, by the virtual guest, at least a portion of the allocation of run-time memory to be inaccessible by the virtual machine manager.

Protecting memory of a virtual guest

The method for protecting memory of a virtual guest includes initializing a virtual guest on a host computing system. The host computing system includes a virtual machine manager that manages operation of the virtual guest. The virtual guest includes a distinct operating environment executing in a virtual operation platform provided by the virtual machine manager. The method includes receiving an allocation of run-time memory for the virtual guest, the allocation of run-time memory comprising a portion of run-time memory of the host computing system. The method includes setting, by the virtual guest, at least a portion of the allocation of run-time memory to be inaccessible by the virtual machine manager.

Growing community of inventors

Austin, TX, United States of America

Christopher J Arges