对于许多小文件来说，什么是最好的文件系统？

Question 1

您不规定“小”有多小，但如果文件足够小且可压缩，embedded_data启用该功能的 ZFS 池可以将“小”文件存储在块指针本身中，从而无需分配块（或更多）文件存储空间，并且还消除了读取或写入文件的 I/O 调用，因为文件数据与文件元数据一起写入块指针本身。

另请注意，ZFS 永远不会用完 inode。

 embedded_data

           This feature improves the performance and compression ratio of
           highly-compressible blocks.  Blocks whose contents can compress
           to 112 bytes or smaller can take advantage of this feature.

           When this feature is enabled, the contents of highly-
           compressible blocks are stored in the block "pointer" itself (a
           misnomer in this case, as it contains the compressed data,
           rather than a pointer to its location on disk).  Thus the space
           of the block (one sector, typically 512 bytes or 4KB) is saved,
           and no additional i/o is needed to read and write the data
           block.

Answer

您不规定“小”有多小，但如果文件足够小且可压缩，embedded_data启用该功能的 ZFS 池可以将“小”文件存储在块指针本身中，从而无需分配块（或更多）文件存储空间，并且还消除了读取或写入文件的 I/O 调用，因为文件数据与文件元数据一起写入块指针本身。

另请注意，ZFS 永远不会用完 inode。

 embedded_data

           This feature improves the performance and compression ratio of
           highly-compressible blocks.  Blocks whose contents can compress
           to 112 bytes or smaller can take advantage of this feature.

           When this feature is enabled, the contents of highly-
           compressible blocks are stored in the block "pointer" itself (a
           misnomer in this case, as it contains the compressed data,
           rather than a pointer to its location on disk).  Thus the space
           of the block (one sector, typically 512 bytes or 4KB) is saved,
           and no additional i/o is needed to read and write the data
           block.

Question 2

假设您想要优化磁盘空间的使用（不仅是 inode 计数，也许还包括访问时间）：

您可能需要一个文件系统块再分配/尾部合并以便将小数据合并到物理磁盘上的一个分配单元（“簇”）中。

此外，根据您的情况，控制文件系统的簇大小可能是明智的，以节省空间。最佳值可以通过测试来确定。

Linux 的一个稳定候选者是btrfs.

当然，如果您乐意使用ext4（并且可能不是空间最优），您可以重新创建您的文件系统（将数据复制到其他地方以首先备份！），并可以选择很多 inode。

从mke2fs(8)：

   -N number-of-inodes
          Overrides the default calculation of the number of inodes that
          should be reserved for the filesystem (which is based on the number
          of blocks and the  bytes-per-inode ratio).  This allows the user to
          specify the number of desired inodes directly.

Answer