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I need to log disk statistics (MB/read, MB/write) of block devices. As I understand, iostat shows an average value. This is not exactly what I want when I'm about to monitor a server. Is there a way to show current values rather than the average?


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up vote 2 down vote accepted


iostat 1

or for more detailed view

iostat -x 1

You should also check out command sar. Actually, in your case sar is probably what you want since you need the actual readings instead of averages. For example, sar -d 1 1 shows you I/O statistics.

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iostat 1 prints the statistics every 1 second. This is not suitable for monitoring. iostat 1 1 limits it to one output, but it seems the values are average again. I got exactly the same stats as yesterday. – Daniel Oct 24 '11 at 6:43
OK then, I edited my reply a bit. – Janne Pikkarainen Oct 24 '11 at 6:47

Use the -y option to suppress the first print being averages:

iostat -y 1 1
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This should be the accepted answer as the -y actually accomplishes what the OP was asking for. – Tony Cesaro Jul 6 '15 at 16:36

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