why sar -b 只有pread/s 和 pwrit/s列有数据，其他列数值都是0?

cnsun

HP-UX 上结果正常，是否有参数需要设置？请指教！

悟人

看看这个,应该能明白点:\r\nReports buffer activity for transfers, accesses, and cache (kernel block\r\nbuffer cache) hit ratios per second. Access to most files in AIX Version 3\r\nbypasses kernel block buffering and therefore does not generate these\r\nstatistics. However, if a program opens a block device or a raw character device\r\nfor I/O, traditional access mechanisms are used making the generated statistics\r\nmeaningful