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请教各位大虾：块设备和字符设备的区别以及它们的用途和优缺点！
是啊，这点也许大家都觉得奇怪，但我想我有责任进一步说明这点！在这我给诸位列出二者之间的比较，资料来自sybase公司培训教材！
Advantages of Operating System Files on UNIX:
Potential advantages to using operating system files rather than raw partitions:
1>;Response time for queries may be faster:
Requested page may be found in the file system cache even when not found in the Sybase buffer cache
2>;Operating system sequential prefetch may be faster:
Operating system can fetch more than 16K from disk
3>;Reads are at least as fast as reads from raw partitions
4>;Devices created on file systems that support greater than 4GB physical memory can take advantage of a large file system cache
File systems are easier to manage than raw partitions
Sybase Devices on Windows NT: Raw Versus File System:
On Windows NT, choices for Sybase devices are:
1>;FAT files
2>;NTFS files
3>;Raw partitions
For both NTFS files and raw partitions:
1>;Asynchronous I/O is available
2>;Writes are reliable
3> erformance is nearly identical
Because files are easier to work with, using NTFS files for Sybase devices is recommended
至于如何选择，还是自己拿主意吧，哈哈......
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发表于 2002-08-01 09:57
