Hi It happened again,and worse thing is that my system went to crash.we can even not connect to it with ssh. I use the sar command to capture the statistics information about it.Here are my details:
[1]cpu(by using sar -u),we have to restart our system just as the red font LINUX RESTART in the logs. -------------------------------------------------------------------------------------------------- 03:00:01 PM all 7.61 0.00 0.92 0.07 0.00 91.40 03:10:01 PM all 7.71 0.00 1.29 0.06 0.00 90.94 03:20:01 PM all 7.62 0.00 1.98 0.06 0.00 90.34 03:30:35 PM all 5.65 0.00 31.08 0.04 0.00 63.23 03:42:40 PM all 47.58 0.00 52.25 0.00 0.00 0.16 Average: all 8.21 0.00 1.57 0.05 0.00 90.17 04:42:04 PM LINUX RESTART 04:50:01 PM CPU %user %nice %system %iowait %steal %idle 05:00:01 PM all 3.49 0.00 0.62 0.15 0.00 95.75 05:10:01 PM all 9.03 0.00 0.92 0.28 0.00 89.77 05:20:01 PM all 7.06 0.00 0.78 0.05 0.00 92.11 05:30:01 PM all 6.67 0.00 0.79 0.06 0.00 92.48 05:40:01 PM all 6.26 0.00 0.76 0.05 0.00 92.93 05:50:01 PM all 5.49 0.00 0.71 0.05 0.00 93.75 -------------------------------------------------------------------------------------------------- [2]mem(by using sar -r) -------------------------------------------------------------------------------------------------- 03:00:01 PM 1519272 196633272 99.23 361112 76364340 143574212 47.77 03:10:01 PM 1451764 196700780 99.27 361196 76336340 143581608 47.77 03:20:01 PM 1453400 196699144 99.27 361448 76248584 143551128 47.76 03:30:35 PM 1513844 196638700 99.24 361648 76022016 143828244 47.85 03:42:40 PM 1481108 196671436 99.25 361676 75718320 144478784 48.07 Average: 5051607 193100937 97.45 362421 81775777 142758861 47.50 04:42:04 PM LINUX RESTART 04:50:01 PM kbmemfree kbmemused %memused kbbuffers kbcached kbcommit %commit 05:00:01 PM 154357132 43795412 22.10 92012 18648644 134950460 44.90 05:10:01 PM 136468244 61684300 31.13 219572 31709216 134966548 44.91 05:20:01 PM 135092452 63060092 31.82 221488 32162324 134949788 44.90 05:30:01 PM 133410464 64742080 32.67 233848 32793848 134976828 44.91 05:40:01 PM 132022052 66130492 33.37 235812 33278908 135007268 44.92 05:50:01 PM 130630408 67522136 34.08 237140 33900912 135099764 44.95 Average: 136996792 61155752 30.86 206645 30415642 134991776 44.91 -------------------------------------------------------------------------------------------------- As the blue font parts show that my hardware crash from 03:30:35.It is hung up until I restart it manually at 04:42:04 ALl the above information just snapshot the performance when it crashed while there is nothing cover the reason.I have also check the /var/log/messages and find nothing useful. Note that I run the command- sar -v .It shows something abnormal: ------------------------------------------------------------------------------------------------ 02:50:01 PM 11542262 9216 76446 258 03:00:01 PM 11645526 9536 76421 258 03:10:01 PM 11748690 9216 76451 258 03:20:01 PM 11850191 9152 76331 258 03:30:35 PM 11972313 10112 132625 258 03:42:40 PM 12177319 13760 340227 258 Average: 8293601 8950 68187 161 04:42:04 PM LINUX RESTART 04:50:01 PM dentunusd file-nr inode-nr pty-nr 05:00:01 PM 35410 7616 35223 4 05:10:01 PM 137320 7296 42632 6 05:20:01 PM 247010 7296 42839 9 05:30:01 PM 358434 7360 42697 9 05:40:01 PM 471543 7040 42929 10 05:50:01 PM 583787 7296 42837 13 ------------------------------------------------------------------------------------------------ and I check the man info about the -v option : ------------------------------------------------------------------------------------------------ *-v* Report status of inode, file and other kernel tables. The following values are displayed: *dentunusd* Number of unused cache entries in the directory cache. *file-nr* Number of file handles used by the system. *inode-nr* Number of inode handlers used by the system. *pty-nr* Number of pseudo-terminals used by the system. ------------------------------------------------------------------------------------------------ Is the any clue about the crash? Would you please give me some suggestions? Best Regards. 2016-03-16 14:01 GMT+08:00 YouPeng Yang <yypvsxf19870...@gmail.com>: > 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. > > > ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > #!/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 > > > > ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > 2016-03-08 21:39 GMT+08:00 YouPeng Yang <yypvsxf19870...@gmail.com>: > >> 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 <apa...@elyograg.org>: >> >>> 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 >>> >>> >> >