 安装虚拟机时报未知错误，not enough free space in volunm group?

这两天在VMware上安装centos7系统时报了下面这个错，自己对磁盘分区和内存管理也不是很了解。
这个地方已经卡了我很久，搜遍整个网络都没有找到具体的解决方法，请求各位大牛看看到底该怎么解决这个问题呢？感激不尽！！
 Snakermaster 问题已经解决了，是创建虚拟机时分配的内存太小，这套系统默认是50G,但我只给了他20个G，希望新手朋友勿入此坑
 大约一年之前 回复
提示你的空间不足啊。检查下你的虚拟机分配的分区是不是足够，特别是home分区。
另外你的存放虚拟机磁盘镜像的物理计算机的硬盘空间是否足够。
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 Doors and Penguins 的计算
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 Average is not Fast Enough! 程序不太会
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 Guard 的设计的问题
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 Assignment Tools 工具问题
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