9.2. 使用 pminfo 检查 XFS 性能指标

先决条件

• 已安装 PCP。如需更多信息，请参阅安装并启用 PCP。

流程

• 显示 XFS PMDA 提供的所有可用指标列表：

  # pminfo xfs

• 显示各个指标的信息。以下示例使用 pminfo 工具检查特定的 XFS 读和写指标：

  • 显示 xfs.write_bytes 指标的简短描述：

    # pminfo --oneline xfs.write_bytes
    
    xfs.write_bytes [number of bytes written in XFS file system write operations]

  • 显示 xfs.read_bytes 指标的长描述：

    # pminfo --helptext xfs.read_bytes
    
    xfs.read_bytes
    Help:
    This is the number of bytes read via read(2) system calls to files in
    XFS file systems. It can be used in conjunction with the read_calls
    count to calculate the average size of the read operations to file in
    XFS file systems.

  • 获取 xfs.read_bytes 指标的当前性能值：

    # pminfo --fetch xfs.read_bytes
    
    xfs.read_bytes
        value 4891346238

  • 使用 pminfo 获取每个设备 XFS 指标：

    # pminfo --fetch --oneline xfs.perdev.read xfs.perdev.write
    
    xfs.perdev.read [number of XFS file system read operations]
    inst [0 or "loop1"] value 0
    inst [0 or "loop2"] value 0
    
    xfs.perdev.write [number of XFS file system write operations]
    inst [0 or "loop1"] value 86
    inst [0 or "loop2"] value 0