Abstract: A transmission control protocol (TCP) flow control method is provided, which comprises: sending a data packet from a packet processor to a receiver and storing a copy of the data packet; receiving a current ACK packet with a current packet number; determining whether the current packet number is identical to a last packet number and whether a last substitute ACK packet generated by the input ACK filter exists; and performing steps respectively corresponding to different results of this determination to avoid TCP congestion control timely. A TCP flow control device performing the method is also disclosed.

Abstract: A transmission control protocol (TCP) flow control method is provided, which comprises: sending a data packet from a packet processor to a receiver and storing a copy of the data packet; receiving a current ACK packet with a current packet number; determining whether the current packet number is identical to a last packet number and whether a last substitute ACK packet generated by the input ACK filter exists; and performing steps respectively corresponding to different results of this determination to avoid TCP congestion control timely. A TCP flow control device performing the method is also disclosed.

Abstract: A control method of a system supporting fault tolerance is provided, at first, a first host executes a transmission control protocol agent to receive a data stream from a client device. Then the TCP agent transmits an acknowledgement packet to the client device in response to the data stream from the client device. Then the TCP agent determines whether a fault tolerance mechanism of the virtual machine is activated. When the TCP agent determines that the fault tolerance mechanism of the virtual machine is activated, the TCP agent determines whether the virtual machine operates in a running state. When the TCP agent determines that the virtual machine is not in the running state, the TCP agent temporarily storing the data stream. When the TCP agent determines that the virtual machine operates in a running state, the TCP agent transmits the data stream to the virtual machine.

Abstract: A fault tolerance method and system for a virtual machine group is proposed. The method includes: establishing fault tolerance backup connections of virtual machines between a virtual machine hypervisor of at least one primary host and a virtual machine hypervisor of at least one backup host to perform fault tolerance backups of the virtual machines, wherein the plurality of virtual machines are included in a fault tolerance group; when a synchronizer determines that a failover of at least one first virtual machine among the primary virtual machines in the fault tolerance group is being performed.

Abstract: A fault tolerance method and system for a virtual machine group is proposed. The method includes: establishing fault tolerance backup connections of virtual machines between a virtual machine hypervisor of at least one primary host and a virtual machine hypervisor of at least one backup host to perform fault tolerance backups of the virtual machines, wherein the plurality of virtual machines are included in a fault tolerance group; when a synchronizer determines that a failover of at least one first virtual machine among the primary virtual machines in the fault tolerance group is being performed.

Abstract: A data processing method, a data processing system and a computer program product are provided. The data processing method includes executing a running operation. The data processing method also includes suspending the running operation at a preset time point in a period of the running operation and calculating a remaining processing time according to a transfer amount of a plurality of dirty pages which are collected before the preset time point in the period of the running operation. The data processing method further includes continuing to execute the running operation, suspending the running operation, and executing a snapshot operation to generate a corresponding data snapshot based on the remaining processing time, and executing a transfer operation to transfer the corresponding data snapshot.

Abstract: A data processing method, a data processing system and a computer program product are provided. The data processing method includes executing a running operation. The data processing method also includes suspending the running operation at a preset time point in a period of the running operation and calculating a remaining processing time according to a transfer amount of a plurality of dirty pages which are collected before the preset time point in the period of the running operation. The data processing method further includes continuing to execute the running operation, suspending the running operation, and executing a snapshot operation to generate a corresponding data snapshot based on the remaining processing time, and executing a transfer operation to transfer the corresponding data snapshot.

Abstract: A server backup method and a backup system using the server backup method are provided. The server backup method includes continuously collecting a plurality of dirty pages during a running operation and determining a backup start time point according to a quantity of the collected dirty pages. The server backup method also includes suspending the running operation according to the backup start time point and executing a backup snapshot operation to generate a data backup snapshot corresponding to the dirty pages, and executing a backup transmission operation to transmit the data backup snapshot.

Abstract: A server backup method and a backup system using the server backup method are provided. The server backup method includes continuously collecting a plurality of dirty pages during a running operation and determining a backup start time point according to a quantity of the collected dirty pages. The server backup method also includes suspending the running operation according to the backup start time point and executing a backup snapshot operation to generate a data backup snapshot corresponding to the dirty pages, and executing a backup transmission operation to transmit the data backup snapshot.

Abstract: A method for sharing memories of virtual machines is provided. The method is applied for a computer system configured to execute at least one virtual machine. The method includes the following steps. A memory map corresponding to the virtual machines is obtained, wherein usage states of memory pages of the virtual machine are stored in the corresponding memory map. Unused memory pages of the virtual machines are marked as free pages according to the corresponding memory map. The free pages of the virtual machines are shared. Therefore, the unused memory pages in the virtual machine can be shared. A computer system using the foregoing method is also provided.

Abstract: In one embodiment, an apparatus for managing hypercalls in a hypervisor having an interrupt handler and a schedule is described. A deferrable low-overhead hypercall (DLH) module is configured to assign a separate DLH queue to each of a plurality of virtual machines when the virtual machine is initialized. Each entry in the separate DLH queue represents a hypercall routine. When one of the virtual machines notifies the interrupt handler of at least a deferrable hypercalls to be executed, the scheduler selects at least a virtual CPU (VCPU) and assigns them to the virtual machine to run on at least a physical CPU (PCPU). The DLH module executes the at least a deferrable hypercall inserted in a DLH queue assigned to the virtual machine before restoring the VCPU context to the virtual machine having the at least an assigned VCPU.

Abstract: A method for sharing memories of virtual machines is provided. The method is applied for a computer system configured to execute at least one virtual machine. The method includes the following steps. A memory map corresponding to the virtual machines is obtained, wherein usage states of memory pages of the virtual machine are stored in the corresponding memory map. Unused memory pages of the virtual machines are marked as free pages according to the corresponding memory map. The free pages of the virtual machines are shared. Therefore, the unused memory pages in the virtual machine can be shared. A computer system using the foregoing method is also provided.

Abstract: In one embodiment, an apparatus for managing hypercalls in a hypervisor having an interrupt handler and a schedule is described. A deferrable low-overhead hypercall (DLH) module is configured to assign a separate DLH queue to each of a plurality of virtual machines when the virtual machine is initialized. Each entry in the separate DLH queue represents a hypercall routine. When one of the virtual machines notifies the interrupt handler of at least a deferrable hypercalls to be executed, the scheduler selects at least a virtual CPU (VCPU) and assigns them to the virtual machine to run on at least a physical CPU (PCPU). The DLH module executes the at least a deferrable hypercall inserted in a DLH queue assigned to the virtual machine before restoring the VCPU context to the virtual machine having the at least an assigned VCPU.