lvm中的pe默认是4M 最大能支持多大 1T?2T

看下手册就知道了。古老的lvm1格式，有网上流传很广的说法，256G限制。

如果是lvm2格式的，基本无限制，限制在于服务器本身的对硬盘的识别和cpu是32还是64，另一个就是系统的内核版本，2.4前的限制2T

以下手册原文：

If the volume group metadata uses lvm1 format, extents can vary in size from 8KB to 16GB and there is a limit of 65534 extents
in each logical volume.  The default of 4 MB leads to a maximum logical volume size of around 256GB.

If the volume group metadata uses lvm2 format those restrictions do not apply, but having a large number of extents will  slow
down the tools but have no impact on I/O performance to the logical volume.  The smallest PE is 1KB.

The 2.4 kernel has a limitation of 2TB per block device.