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I am trying to understand why my system is running slowly. I found the sar command, but wanted to know the difference between sar -B and sar -W

I read the man page, and I understand that -B gives me the paging statistics and -W gives me the swapping statistics. What I would like to understand is the following:

What is the correlation between the two sets of statistics.

When should I be concerned about -B and when about -W? ie, what values from each command should I be concerned with?

Which statistic is more closely related to system performance


share|improve this question
Which version of sar are you running? (there are multiple implementations) -W on my Debian box shows -W Statistics about errors for IP (version 4) traffic. Without knowing the particulars for your implementation it is difficult to check the man pages, and source to see exactly what statistics are being checked and reported. – Zoredache Aug 20 '14 at 21:25
sar -V gives me sysstat version 7.0.2 – Mark Aug 20 '14 at 21:44
man sar can help you – c4f4t0r Aug 21 '14 at 21:53

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