May 2011 Archives

fedora15刚刚发布，于是我开始安装fedora15之旅。

没有光驱盘，也有dos启动的软硬盘，我系统就是一个windows7系统，怎么办呢，只好找同事借了一个grub的usb启动盘，终于开始grub的引导，usb很不稳定，弄不好就不识别了，一个好的方式就是进入windows7系统，让usb识别硬盘之后，然后使用usb启动。

记得安装fedora14的时候，还可以选择硬盘进行安装，但是发现fedora15默认只能使用网络进行安装，竟然有限制了。

于是不甘心的查查官方的手册，发现：

4.5. Selecting an Installation Method

What type of installation method do you wish to use? The following installation methods are available:

DVD

If you have a DVD drive and the Fedora DVD you can use this method. Refer to Section 8.3.1, “Installing from DVD”, for DVD installation instructions.

If you booted the installation from a piece of media other than the
installation DVD, you can specify the DVD as the installation source
with the linux askmethod or linux repo=cdrom:device:/device boot option, or by selecting Local CD/DVD on the Installation Method menu (refer to Section 8.3, “Installation Method”).

CD set

If you have a CD drive and the set of Fedora CDs you can use this method. Refer to Section 8.3.1, “Installing from DVD” for CD installation instructions.

If you booted the installation from a piece of media other than the
set of installation CDs, you can specify the CD as the installation
source with the linux askmethod or linux repo=cdrom:device:/device boot option, or by selecting Local CD/DVD on the Installation Method menu (refer to Section 8.3, “Installation Method”).

Live CD

If you have a CD drive and the Fedora live CD you can use this method. The live CD desktop includes an icon labeled Install to Hard Drive. Refer to Section 8.3.1, “Installing from DVD” for CD installation instructions.

Hard Drive

If you have copied the Fedora ISO images to a local hard drive, you can use this method. You need a boot CD-ROM (use the linux askmethod or linux repo=hd:device:/path boot option), or by selecting Hard drive on the Installation Method menu (refer to Section 8.3, “Installation Method”). Refer to Section 8.3.2, “Installing from a Hard Drive”, for hard drive installation instructions.

NFS

If you are installing from an NFS server using ISO images or a
mirror image of Fedora, you can use this method. You need a boot CD-ROM
(use the linux askmethod or linux repo=nfs:server :options:/path boot option, or the NFS directory option on the Installation Method menu described in Section 8.3, “Installation Method”). Refer to Section 8.3.4, “Installing via NFS” for network installation instructions. Note that NFS installations may also be performed in GUI mode.

URL

If you are installing directly from an HTTP (Web) server or FTP server, use this method. You need a boot CD-ROM (use the linux askmethod, linux repo=ftp://user:password@host/path, or linux repo=http://host/path boot option, or the URL option on the Installation Method menu described in Section 8.3, “Installation Method”). Refer to Section 8.3.5, “Installing via FTP or HTTP”, for FTP and HTTP installation instructions.

fedora15刚刚发布，感兴趣的同学赶快试哟！

43M/s，92s下载完毕，网易镜像好快的速度！

    DMA的英文拼写是“Direct Memory Access”（存储器直接访问）。这是指一种高速的数据传输操作，允许在外部设备和存储器之间直接读写数据，既不通过CPU，也不需要CPU干预。整个数 据传输操作在一个称为"DMA控制器"的控制下进行的。CPU除了在数据传输开始和结束时做一点处理外，在传输过程中CPU可以进行其他的工作。这样，在 大部分时间里，CPU和输入输出都处于并行操作。因此，使整个计算机系统的效率大大提高。
    （Ultra-DMA/33），1996年由Intdl和Quantum制定的一种数据传输方式，该方式I/O系统的突发数据传输速度可达33MB/s，还可以降低I/O系统对CPU资源的占用率。现在又出现了UDMA/66，速度多出两倍。

      PIO的英文拼写是“Programming Input/Output Model”，PIO模式是一种通过CPU执行I/O端口指令来进行数据的读写的数据交换模式。是最早先的硬盘数据传输模式，数据传输速率低下，CPU占 有率也很高，大量传输数据时会因为占用过多的CPU资源而导致系统停顿，无法进行其它的操作。PIO数据传输模式又分为PIO mode 0、PIO mode 1、PIO mode 2、PIO mode 3、PIO mode 4几种模式，数据传输速率从3.3MB/s到16.6MB/s不等。受限于传输速率低下和极高的CPU占有率，这种数据传输模式很快就被淘汰。