红帽全球峰会2.2. 计算 Compute 节点上的保留主机内存
要确定主机进程保留的 RAM 总量，您需要为每个主机进程分配足够的内存：
- 例如，在主机上运行的资源（如 OSD 消耗 3 GB 内存）。
- 托管实例所需的仿真程序开销。
- 每个实例的虚拟机监控程序。
在计算了内存的额外需求后，使用以下公式来帮助确定每个节点上主机进程保留的内存量：
NovaReservedHostMemory = total_RAM - ( (vm_no * (avg_instance_size + overhead)) + (resource1 * resource_ram) + (resourcen * resource_ram))-
将
vm_no替换为实例数量。 -
将
avg_instance_size替换为每个实例可以使用的平均内存量。 -
使用每个实例所需的 hypervisor
开销替换开销。 -
将
resource1和所有资源（直到<resourcen>）替换为节点上的资源类型数量。 -
将
resource_ram替换为此类资源的 RAM 量。
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