RN104 - process "find" uses 100% cpu for several hours

With no other information, I'd guess that it's updatedb, running way too often because of a misconfigured cron job. But top can show you each process's parent so you won't have to guess.

Find is used for various things. updateDB (used to update the list of files and folders for the command locate) is one of them.
The BTRFS defrag also uses find to locate the files and pass them to the defragger.
Maybe the scrub process or the snapshot features are calling it too ? not sure for those ones.
I also don't know for the virus scanner, I thinks it's all contained in ctscand but not sure.

The CPU is currently at 100%

TOP looks like this:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
27620 guest 30 10 5840 1964 884 R 73.1 0.4 350:40.89 find
4390 root 20 0 464m 64m 2256 S 23.3 13.1 101:15.32 java
3 root 20 0 0 0 0 S 0.3 0.0 0:51.66 ksoftirqd/0
6 root -2 0 0 0 0 S 0.3 0.0 3:24.45 rcu_kthread
12008 root 20 0 5372 1516 1052 R 0.3 0.3 0:00.10 top
1 root 20 0 5572 2828 1268 S 0.0 0.6 0:13.19 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.74 kthreadd
7 root rt 0 0 0 0 S 0.0 0.0 0:00.92 watchdog/0
8 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 khelper
177 root 20 0 0 0 0 S 0.0 0.0 0:00.00 sync_supers
179 root 20 0 0 0 0 S 0.0 0.0 0:00.00 bdi-default
181 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 kblockd
187 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 ata_sff
194 root 20 0 0 0 0 S 0.0 0.0 0:00.00 khubd
199 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 md
217 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 rpciod
234 root 20 0 0 0 0 S 0.0 0.0 3:56.43 kswapd0
283 root 20 0 0 0 0 S 0.0 0.0 0:00.00 fsnotify_mark
299 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 nfsiod
319 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 xfsalloc
320 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 xfs_mru_cache
321 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 xfslogd
322 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 xfsdatad
323 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 xfsconvertd
333 root 0 -20 0 0 0 S 0.0 0.0 0:00.00 crypto
349 root 20 0 0 0 0 S 0.0 0.0 0:00.00 crypto


when I fetch more details with "ps aux" i get this:

guest 27620 95.4 0.2 5048 1256 ? RN 06:25 352:26 /usr/bin/find / -ignore_readdir_race ( -fstype NFS -o -fstype nfs -o -fstype nfs4 -o -fstype afs -o -fstype binfmt_misc -o -fstype proc -o -fstype smbfs -o -fstype autofs -o -fstype iso9660 -o -fstype ncpfs -o -fstype coda -o -fstype devpts -o -fstype ftpfs -o -fstype devfs -o -fstype mfs -o -fstype shfs -o -fstype sysfs -o -fstype cifs -o -fstype lustre_lite -o -fstype tmpfs -o -fstype usbfs -o -fstype udf -o -fstype ocfs2 -o -type d -regex \(^/tmp$\)\|\(^/usr/tmp$\)\|\(^/var/tmp$\)\|\(^/afs$\)\|\(^/amd$\)\|\(^/alex$\)\|\(^/var/spool$\)\|\(^/sfs$\)\|\(^/media$\)\|\(^/var/lib/schroot/mount$\) ) -prune -o -print0

I dont know if this gives you any clue.

UpdateDB is running, but with no CPU load

root 12310 0.0 0.1 4104 800 pts/0 S+ 12:37 0:00 grep update
root 27599 0.0 0.1 1752 520 ? SN 06:25 0:00 /bin/sh /usr/bin/updatedb.findutils
root 27607 0.0 0.0 1752 328 ? SN 06:25 0:00 /bin/sh /usr/bin/updatedb.findutils

Try "killall updatedb" next time you see the CPU load spike. Killing the process won't corrupt the locate database; updatedb builds a temporary database as it runs, and only replaces the real database if the run successfully completes.

Hi. Thanks.
I've tried killall updatedb, but it fails as updatedb does not run any processes.

root@NAS01:~# top
top - 08:13:24 up 16 days, 20:33, 1 user, load average: 1.77, 1.89, 1.91
Tasks: 149 total, 2 running, 147 sleeping, 0 stopped, 0 zombie
%Cpu(s): 1.0 us, 54.4 sy, 43.0 ni, 0.0 id, 1.6 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem: 507236 total, 466208 used, 41028 free, 2580 buffers
KiB Swap: 523708 total, 26508 used, 497200 free, 86900 cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
25942 guest 39 19 5012 1224 888 R 96.4 0.2 105:20.72 find
2120 root 19 -1 182m 13m 2916 S 1.0 2.7 49:08.38 readynasd
30304 root 20 0 5260 1496 1052 R 0.7 0.3 0:00.06 top
864 root 20 0 0 0 0 S 0.3 0.0 4:32.26 btrfs-endio-met
1 root 20 0 5572 2680 1120 S 0.0 0.5 0:13.92 systemd

root@NAS01:~# killall updatedb
updatedb: no process found
root@NAS01:~#

:?

I somewhat found a solution, or lowered the number of hours "find" runs in the system.

I modified the file /etc/cron.daily/locate

In the file, I pruned the following:
PRUNEPATHS="/data/._share/Documents/.snapshot/ ./data/._share/Music/.snapshot/ ./data/._share/Pictures/.snapshot/" as well as the original pruned paths.

This refers to my shares, of which I know contains alot of data.

The next time locate ran, it did the entire find and locate thingie in 10 hours insted of 23 or so..

I still feel that this is the wrong approach to the problem, but it seems indeed as the problem is within "locate"'s daily rutine in the combination of the way ReadyNas 104 creates shapshots.

More good ideas is more than welcome :)