Hello
The problem appears several times ,however I could not capture the top
output .My script is as follows code.
I check the sys cpu usage whether it exceed 30%.the other metric
information can be dumpped successfully except the top .
Would you like to check my script that I am not able to figure out what is
wrong.
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#!/bin/bash
while :
do
sysusage=$(mpstat 2 1 | grep -A 1 "%sys" | tail -n 1 | awk '{if($6 <
30) print 1; else print 0;}' )
if [ $sysusage -eq 0 ];then
#echo $sysusage
#perf record -o perf$(date +%Y%m%d%H%M%S).data -a -g -F 1000 sleep
30
file=$(date +%Y%m%d%H%M%S)
top -n 2 >> top$file.data
iotop -b -n 2 >> iotop$file.data
iostat >> iostat$file.data
netstat -an | awk '/^tcp/ {++state[$NF]} END {for(i in state) print
i,"\t",state[i]}' >> netstat$file.data
fi
sleep 5
done
You have new mail in /var/spool/mail/root
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2016-03-08 21:39 GMT+08:00 YouPeng Yang <[email protected]>:
> Hi all
> Thanks for your reply.I do some investigation for much time.and I will
> post some logs of the 'top' and IO in a few days when the crash come again.
>
> 2016-03-08 10:45 GMT+08:00 Shawn Heisey <[email protected]>:
>
>> On 3/7/2016 2:23 AM, Toke Eskildsen wrote:
>> > How does this relate to YouPeng reporting that the CPU usage increases?
>> >
>> > This is not a snark. YouPeng mentions kernel issues. It might very well
>> > be that IO is the real problem, but that it manifests in a non-intuitive
>> > way. Before memory-mapping it was easy: Just look at IO-Wait. Now I am
>> > not so sure. Can high kernel load (Sy% in *nix top) indicate that the IO
>> > system is struggling, even if IO-Wait is low?
>>
>> It might turn out to be not directly related to memory, you're right
>> about that. A very high query rate or particularly CPU-heavy queries or
>> analysis could cause high CPU usage even when memory is plentiful, but
>> in that situation I would expect high user percentage, not kernel. I'm
>> not completely sure what might cause high kernel usage if iowait is low,
>> but no specific information was given about iowait. I've seen iowait
>> percentages of 10% or less with problems clearly caused by iowait.
>>
>> With the available information (especially seeing 700GB of index data),
>> I believe that the "not enough memory" scenario is more likely than
>> anything else. If the OP replies and says they have plenty of memory,
>> then we can move on to the less common (IMHO) reasons for high CPU with
>> a large index.
>>
>> If the OS is one that reports load average, I am curious what the 5
>> minute average is, and how many real (non-HT) CPU cores there are.
>>
>> Thanks,
>> Shawn
>>
>>
>
