<p><strong><span style="font-size:18px">技术本质</span></strong></p> <p><span style="font-size:16px"><strong>容器</strong></span></p> <p>容器的实现方式是通过内核技术进行形式上的模拟，本质上容器还是一个进程，技术支撑是Cgroup/Namespace/Capability，主要从资源限制、环境隔离、权限管理三个维度进行模拟。</p> <p><img src="https://pcp-portal-sca.obs-cn-shenzhen.pinganyun.com/pcp-portal-sca/20190409143914-183fdb4e9efb.png" style="height:288px; width:372px" /></p> <p><span style="font-size:16px"><strong>虚拟机</strong></span></p> <p>虚拟机的实现方式是对底层设备的抽象虚拟，实现方式是Hypervisor，本质实际上是CPU等硬件的VT技术，使用VMware/VirtualBox一定要在BIOS里开启VT设置，GPU目前不支持VT，所有不能虚拟化，公有云或Kubernetes的GPU都是独占的，即资源配置只能设置为个位数，不能有小数。</p> <p><img src="https://pcp-portal-sca.obs-cn-shenzhen.pinganyun.com/pcp-portal-sca/20190409143924-126a2c599877.png" style="height:299px; width:375px" /></p> <p>&nbsp;</p> <p><span style="font-size:18px"><strong>性能对比</strong></span></p> <p>容器与虚拟机的性能对比如下表所示：</p> <table border="1" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="background-color:#ededed; vertical-align:top; width:106px"> <p><strong>特性</strong></p> </td> <td style="background-color:#ededed; vertical-align:top; width:114px"> <p><strong>容器</strong></p> </td> <td style="background-color:#ededed; vertical-align:top; width:120px"> <p><strong>虚拟机</strong></p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>操作系统</p> </td> <td style="vertical-align:top; width:114px"> <p>Linux为主</p> </td> <td style="vertical-align:top; width:120px"> <p>非常广泛</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>技术本质</p> </td> <td style="vertical-align:top; width:114px"> <p>模拟</p> </td> <td style="vertical-align:top; width:120px"> <p>虚拟</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>隔离策略</p> </td> <td style="vertical-align:top; width:114px"> <p>Namespace</p> </td> <td style="vertical-align:top; width:120px"> <p>Hypervisor</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>启动时间</p> </td> <td style="vertical-align:top; width:114px"> <p>秒级</p> </td> <td style="vertical-align:top; width:120px"> <p>分钟级</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>资源损耗</p> </td> <td style="vertical-align:top; width:114px"> <p>0-5%</p> </td> <td style="vertical-align:top; width:120px"> <p>5-15%</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>镜像存储</p> </td> <td style="vertical-align:top; width:114px"> <p>KB-MB</p> </td> <td style="vertical-align:top; width:120px"> <p>GB-TB</p> </td> </tr> <tr> <td style="vertical-align:top; width:106px"> <p>集群规模</p> </td> <td style="vertical-align:top; width:114px"> <p>近万</p> </td> <td style="vertical-align:top; width:120px"> <p>数百</p> </td> </tr> </tbody> </table> <p>&nbsp;</p> <p>&nbsp;</p>