Abstract: A first set of instructions, which is provided access to a first address space, is scheduled for execution at a first hardware thread of a processor. Prior to executing an instruction of a second set of instructions, which accesses a second address space, at the first hardware thread, a determination is made that the second address space is accessible from a second hardware thread of the processor.

Abstract: A first set of instructions, which is provided access to a first address space, is scheduled for execution at a first hardware thread of a processor. Prior to executing an instruction of a second set of instructions, which accesses a second address space, at the first hardware thread, a determination is made that the second address space is accessible from a second hardware thread of the processor.

Abstract: A computing device including executable processes may determine that a future likelihood of access for virtual memory pages of an executable process are below a threshold likelihood of access based on an execution status of the executable process or a tracking of memory accesses to the virtual memory pages of the executable process. Responsive to this determination, memory pages found to store contents matching that of memory pages mapped to other processes may be unmapped from the process and released for reuse by the computing device. The virtual memory pages may then be marked as being shared with the similar memory pages mapped to the other processes. At a later time, the memory pages of the process may be configured to be non-shared, the configuring including either copying respective shared pages to non-shared pages or enabling a processor exception on access to the memory pages.

Abstract: As part of a compute instance migration, a compute instance which was executing at a first server begins execution at a second server before at least some state information of the compute instance has reached the second server. In response to a determination that a particular page of state information is not present at the second server, a migration manager running at one or more offload cards of the second server causes the particular page to be transferred to the second server via a network channel set up between the offload cards of both servers, and stores the page into main memory of the second server.

Abstract: An opportunistic hypervisor determines that a guest virtual machine of a virtualization host has voluntarily released control of a physical processor. The hypervisor uses the released processor to identify and initiate a virtualization management task which has not been completed. In response to determining that at least a portion of the task has been performed, the hypervisor enters a quiescent state, releasing the physical processor to enable resumption of the guest virtual machine.

Abstract: An interrupt recovery manager detects that a compute instance has exited a state in which interrupts from one or more interrupt sources were not processed at the compute instance. The recovery manager identifies a source from which interrupts may have been missed by the compute instance, and causes an indication of a potential missed interrupt from that source to be delivered to the compute instance.

Abstract: An offloaded virtualization management component of a virtualization host receives an indication from a hypervisor of a portion of main memory of the host for which memory allocation decisions are not to be performed by the hypervisor. The offloaded virtualization management component assigns a subset of the portion to a particular guest virtual machine and provides an indication of the subset to the hypervisor.

Abstract: An offloaded virtualization management component of a virtualization host receives an indication from a hypervisor of a portion of main memory of the host for which memory allocation decisions are not to be performed by the hypervisor. The offloaded virtualization management component assigns a subset of the portion to a particular guest virtual machine and provides an indication of the subset to the hypervisor.

Abstract: An offloaded virtualization management component of a virtualization host receives an indication from a hypervisor of a portion of main memory of the host for which memory allocation decisions are not to be performed by the hypervisor. The offloaded virtualization management component assigns a subset of the portion to a particular guest virtual machine and provides an indication of the subset to the hypervisor.

Abstract: An opportunistic hypervisor determines that a guest virtual machine of a virtualization host has voluntarily released control of a physical processor. The hypervisor uses the released processor to identify and initiate a virtualization management task which has not been completed. In response to determining that at least a portion of the task has been performed, the hypervisor enters a quiescent state, releasing the physical processor to enable resumption of the guest virtual machine.

Abstract: An opportunistic hypervisor determines that a guest virtual machine of a virtualization host has voluntarily released control of a physical processor. The hypervisor uses the released processor to identify and initiate a virtualization management task which has not been completed. In response to determining that at least a portion of the task has been performed, the hypervisor enters a quiescent state, releasing the physical processor to enable resumption of the guest virtual machine.

Abstract: An opportunistic hypervisor determines that a guest virtual machine of a virtualization host has voluntarily released control of a physical processor. The hypervisor uses the released processor to identify and initiate a virtualization management task which has not been completed. In response to determining that at least a portion of the task has been performed, the hypervisor enters a quiescent state, releasing the physical processor to enable resumption of the guest virtual machine.

Abstract: An offloaded virtualization management component of a virtualization host receives an indication from a hypervisor of a portion of main memory of the host for which memory allocation decisions are not to be performed by the hypervisor. The offloaded virtualization management component assigns a subset of the portion to a particular guest virtual machine and provides an indication of the subset to the hypervisor.