Abstract: Techniques for migrating virtual machines (VMs) in the presence of uncorrectable memory errors are provided. According to one set of embodiments, a source host hypervisor of a source host system can determine, for each guest memory page of a VM to be migrated from the source host system to a destination host system, whether the guest memory page is impacted by an uncorrectable memory error in a byte-addressable memory of the source host system. If the source host hypervisor determines that the guest memory page is impacted, the source host hypervisor can transmit a data packet to a destination host hypervisor of the destination host system that includes error metadata identifying the guest memory page as being corrupted. Alternatively, if the source host hypervisor determines that the guest memory page is not impacted, the source host hypervisor can attempt to read the guest memory page from the byte-addressable memory in a memory exception-safe manner.

Abstract: In one set of embodiments, a hypervisor of a host system can determine that a delta between local and remote memory access latencies for each of a subset of NUMA nodes of the host system is less than a threshold. In response, the hypervisor can enable page sharing across the subset of NUMA nodes, where enabling page sharing comprises associating the subset of NUMA nodes with a single page sharing table, and where the single page sharing table holds entries identifying host physical memory pages of the host system that are shared by virtual machines (VMs) placed on the subset of NUMA nodes.

Abstract: Techniques for resuming a failed data transfer of a virtual disk between a source and destination are disclosed. In one set of embodiments, while the transfer is proceeding, metadata regarding the transfer, including an offset indicating transfer progress, may be periodically stored. Upon determining that the transfer has failed, a copy of the incomplete virtual disk at the destination (i.e., fragment) may be moved to a fragment storage and a record including an identifier of the virtual disk and the offset may be created and stored. At a later point in time, when transfer of the virtual disk is requested to be restarted, the request may be matched against the record to determine whether resumption of the prior transfer operation is possible. If so, the fragment can be moved to its original location at the destination and the transfer can be resumed based on the offset.

Abstract: A method of preserving the contiguity of large pages of a workload during migration of the workload from a source host to a destination host includes the steps of: detecting at the destination host, receipt of a small page of zeros from the source host, wherein, at the source host, the small page is part of one of the large pages of the workload; and upon detecting the receipt of the small page of zeros, storing, at the destination host, all zeros in a small page that is part of one of the large pages of the workload.

Abstract: Techniques for implementing data plane isolation for VM mobility operations are provided. In one set of embodiments, these techniques include creating a virtual network path between a source host system and a destination host system participating in a VM mobility operation, which allows the host systems to exchange data for carrying out the operation without exposing their physical IP addresses to each other and without requiring the use of intermediate proxies. In certain embodiments, the virtual network path can be dynamically established upon initiation of the VM mobility operation and dynamically rolled back upon operation completion, thereby reducing the overhead of virtual path management.

Abstract: Techniques for migrating virtual machines (VMs) in the presence of uncorrectable memory errors are provided. According to one set of embodiments, a source host hypervisor of a source host system can determine, for each guest memory page of a VM to be migrated from the source host system to a destination host system, whether the guest memory page is impacted by an uncorrectable memory error in a byte-addressable memory of the source host system. If the source host hypervisor determines that the guest memory page is impacted, the source host hypervisor can transmit a data packet to a destination host hypervisor of the destination host system that includes error metadata identifying the guest memory page as being corrupted. Alternatively, if the source host hypervisor determines that the guest memory page is not impacted, the source host hypervisor can attempt to read the guest memory page from the byte-addressable memory in a memory exception-safe manner.

Abstract: Techniques for implementing application-assisted VM provisioning operations, and in particular application-assisted live migration, are provided. In one set of embodiments, a hypervisor of a source host system can notify a guest application that the VM within which the guest application runs will be imminently live migrated from the source host system to a destination host system, prior to actually carrying out the live migration. In response, the guest application can execute one or more remedial actions that mitigate or avoid issues which may arise with respect to its runtime operation when the VM is stunned and switched over to the destination host system.

Abstract: In one set of embodiments, during an initial pre-copying phase, copies of the virtual disks of a VM or VM template can be distributed across one or more datastores, prior to the start of any cloning. This effectively seeds each datastore with a disk pool comprising a certain number of copies of the VM/VM template's virtual disks. Then, at the time of receiving a user request to create k clones from the VM/VM template, up to k copies of the VM/VM template's virtual disks that already reside in the disk pools of one or more target datastores can be moved from those disk pools to the clones' home folders on the target datastores, thereby reducing or eliminating the need to create brand new copies of the virtual disks on demand.

Abstract: A method of populating page tables of an executing workload during migration of the executing workload from a source host to a destination host includes the steps of: during transmission of memory pages of the executing workload from the source host to the destination host, populating the page tables of the workload at the destination host, wherein the populating comprises inserting mappings from virtual addresses of the workload to physical addresses of system memory of the destination host for all of the memory pages of the executing workload; and upon completion of transmission of all of the memory pages of the workload, resuming the workload at the destination host.

Abstract: Techniques for migrating virtual machines (VMs) in the presence of uncorrectable memory errors are provided. According to one set of embodiments, a source host hypervisor of a source host system can determine, for each guest memory page of a VM to be migrated from the source host system to a destination host system, whether the guest memory page is impacted by an uncorrectable memory error in a byte-addressable memory of the source host system. If the source host hypervisor determines that the guest memory page is impacted, the source host hypervisor can transmit a data packet to a destination host hypervisor of the destination host system that includes error metadata identifying the guest memory page as being corrupted. Alternatively, if the source host hypervisor determines that the guest memory page is not impacted, the source host hypervisor can attempt to read the guest memory page from the byte-addressable memory in a memory exception-safe manner.

Abstract: A managed object of a virtualized computing environment, which contains the runtime state of a parent virtual machine (VM) and can be placed in any host of the virtualized computing environment, is used for instantly cloning child VMs off that managed object. The managed object is not an executable object (i.e., the state of the managed object is static) and thus it does not require most of the overhead memory associated with a VM. As a result, this managed object can support instant cloning of VMs with a reduction in memory, storage, and CPU overhead relative to when a parent template VM is used.

Abstract: A method of preserving the contiguity of large pages of a workload during migration of the workload from a source host to a destination host includes the steps of: detecting at the destination host, receipt of a small page of zeros from the source host, wherein, at the source host, the small page is part of one of the large pages of the workload; and upon detecting the receipt of the small page of zeros, storing, at the destination host, all zeros in a small page that is part of one of the large pages of the workload.

Abstract: A method of migrating a network file copy (NFC) operation from a first host computing device to a second host computing device includes the steps of: transmitting a first request to the first host computing device to execute the NFC operation, wherein the NFC operation comprises transferring data from a shared datastore to another datastore; after transmitting the first request, selecting the second host computing device to complete the NFC operation in place of the first host computing device, and transmitting a second request to the first host computing device to stop executing the NFC operation; after transmitting the second request, detecting a message indicating that the first host computing device completed the copying of a first portion of the data; and in response to the detection of the message, transmitting a third request to the second host computing device to perform the remainder of the NFC operation.

Abstract: A method of populating page tables of an executing workload during migration of the executing workload from a source host to a destination host includes the steps of: before resuming the workload at the destination host, populating the page tables of the workload at the destination host, wherein the populating comprises inserting mappings from virtual addresses of the workload to physical addresses of system memory of the destination host; and upon completion of populating the page tables, resuming the workload at the destination host.

Abstract: A method of populating page tables of an executing workload during migration of the executing workload from a source host to a destination host includes the steps of: before resuming the workload at the destination host, populating the page tables of the workload at the destination host, wherein the populating comprises inserting mappings from virtual addresses of the workload to physical addresses of system memory of the destination host; and upon completion of populating the page tables, resuming the workload at the destination host.

Abstract: A method of migrating a network file copy (NFC) operation from a first host computing device to a second host computing device includes the steps of: transmitting a first request to the first host computing device to execute the NFC operation, wherein the NFC operation comprises transferring data from a shared datastore to another datastore; after transmitting the first request, selecting the second host computing device to complete the NFC operation in place of the first host computing device, and transmitting a second request to the first host computing device to stop executing the NFC operation; after transmitting the second request, detecting a message indicating that the first host computing device completed the copying of a first portion of the data; and in response to the detection of the message, transmitting a third request to the second host computing device to perform the remainder of the NFC operation.

Abstract: A method of preserving the contiguity of large pages of a workload during migration of the workload from a source host to a destination host includes the steps of: detecting at the destination host, receipt of a small page of zeros from the source host, wherein, at the source host, the small page is part of one of the large pages of the workload; and upon detecting the receipt of the small page of zeros, storing, at the destination host, all zeros in a small page that is part of one of the large pages of the workload.

Abstract: A method of preserving the contiguity of large pages of a workload during migration of the workload from a source host to a destination host includes the steps of: detecting at the destination host, receipt of a small page of zeros from the source host, wherein, at the source host, the small page is part of one of the large pages of the workload; and upon detecting the receipt of the small page of zeros, storing, at the destination host, all zeros in a small page that is part of one of the large pages of the workload.

Abstract: In one set of embodiments, a hypervisor of a host system can determine that a delta between local and remote memory access latencies for each of a subset of NUMA nodes of the host system is less than a threshold. In response, the hypervisor can enable page sharing across the subset of NUMA nodes, where enabling page sharing comprises associating the subset of NUMA nodes with a single page sharing table, and where the single page sharing table holds entries identifying host physical memory pages of the host system that are shared by virtual machines (VMs) placed on the subset of NUMA nodes.

Abstract: A method for migrating a virtual machine (VM) includes establishing a first connection to a first cloud computing system executing a first VM, and establishing a second connection to a second cloud computing system managed by a second cloud provider, which is different form the first cloud provider. The method further includes instantiating a second VM designated as a destination VM in the second cloud computing system, and installing a migration agent on each of the first VM and the second VM. The migration agents execute a migration process of the first VM to the second VM by (1) iteratively copying guest data from the first VM to the second VM until a switchover criteria of the migration operation is met, and (2) copying a remainder of guest data from the first VM to the second VM when the switchover criteria is met.