Method and system for maintaining context event logs without locking in virtual machine

摘要

System for working with shared memory includes a plurality of contexts, each having executable processes writing and reading data; a ring buffer in the shared memory for writing and reading data by the contexts; a software primitive manages access attempts by the contexts to the ring buffer. Each context, upon writing to the ring buffer, is allocated an amount of space up to a maximum available at that moment. The software primitive guarantees consistency of the data written to the ring buffer. The software primitive permits simultaneous writing into the buffer by multiple contexts. After finishing writing to the buffer, the context updates a state of the buffer by decrementing the count of the active writers and/or by shifting the permitting pointers for communicating with writers and readers. A context can read from the buffer only data is marked as valid for reading by the context that wrote that data.

主权项

1. A system for working with shared memory of a computer, comprising:
a) a plurality of Virtual Machines (VMs), each writing and reading data to a ring buffer in the shared memory for storing the data; b) a software primitive for managing access by the VMs to the ring buffer; c) wherein each VM, upon writing to the ring buffer, is allocated an amount of space requested by the VM, up to a maximum available; d) wherein the software primitive guarantees consistency of the data; e) wherein the software primitive permits simultaneous writing into the ring buffer by multiple VMs and simultaneous reading from the ring buffer by multiple VMs; f) wherein a VM that finished writing last opens for reading data of other VMs in the ring buffer; g) wherein a VM that finished writing can open its data to other VMs; h) wherein, after finishing writing to the ring buffer, the VM decrements a count of the active writers and/or shifts the permission pointers for communicating with writers and readers; and i) wherein a VM can read from the buffer only the data that is marked as valid.