High interrupt CPU usage in top

[Oliver Fromme]

Mark Cullen <mark.r.cullen at xxxxxxxxx> wrote:
 > Oliver Fromme wrote:
 > > Have you tried "vmstat -i"?  It might give an indication
 > > if any of the device interrupts is causing the problem.
 > 
 > Yep, doesn't look particularly unusual to me (taken while compiling 
 > multiple things)?
 > 
[omitted some lines for brevity]
 > interrupt                   total       rate
 > clk                       3134621        281
 > fxp0                       176854         15
 > uhci0/fxp1                      0          0
 > ata1                       250336         22
 > Total                     3567308        319

Looks normal indeed.  However, those values are counters
which count since the last reboot, so a short spike will
not necessarily be visible there.

 > Looks like USB is sharing with fxp1? Not that fxp1 is actually even 
 > plugged in or being used at all at the moment!!

In that case it shouldn't do any harm.  Also note that it
hasn't generated any interrupts at all.  So the problem
is caused by something else.

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
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