char
January 29, 2026, 1:27pm
1
Hi everyone, we’re trying to troubleshoot the issues our Discourse installation has been having in the last few days.
We’re running a Contabo cloud vps, 8 cores/32gb/nvme, for a userbase of ~150 people; we’ve had few issues in the last 2 and a half years.
Since last weekend, the instance is having moments of almost-unusability, due to a un unusually high CPU usage.
To troubleshoot this situation, we’ve let the forum in Read Only mode yesterday. I have a few Grafana graphs showing what’s our situation - the three markers indicate where we turned on Read Only, when we restarted the container and when we turned off Read Only.
(a couple more graphs here:
Imgur: The magic of the Internet )
As you can see, usage is pretty high. This started a few days ago, therefore there’s some kind of issue we’ve yet to troubleshoot properly.
After asking the AI assistant before opening a new thread, I can add that Sidekiq has some outlier processes:
Jobs::ProcessBadgeBacklog takes about 2-5 seconds
last DestroyOldDeletionStubs took 475 seconds.
last DirectoryRefreshDaily took 580 seconds.
last TopRefreshToday took 18 seconds.
So, the question is - what could be causing this kind of situation, with the userbase and the hardware we’re using?
Thanks!
3 Likes
Ed_S
January 29, 2026, 4:52pm
2
I think somehow you’re short of RAM. You have 32G. But possibly you have some process or processes using more than expected.
Perhaps capture ps aux in a window about 120 chars wide. Here’s mine:
root@rc-debian-hel:~# ps uax
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.2 167752 9096 ? Ss 2025 4:24 /sbin/init
root 2 0.0 0.0 0 0 ? S 2025 0:00 [kthreadd]
root 3 0.0 0.0 0 0 ? I< 2025 0:00 [rcu_gp]
root 4 0.0 0.0 0 0 ? I< 2025 0:00 [rcu_par_gp]
root 5 0.0 0.0 0 0 ? I< 2025 0:00 [slub_flushwq]
root 6 0.0 0.0 0 0 ? I< 2025 0:00 [netns]
root 8 0.0 0.0 0 0 ? I< 2025 0:00 [kworker/0:0H-events_highpri]
root 10 0.0 0.0 0 0 ? I< 2025 0:00 [mm_percpu_wq]
root 11 0.0 0.0 0 0 ? S 2025 0:00 [rcu_tasks_rude_]
root 12 0.0 0.0 0 0 ? S 2025 0:00 [rcu_tasks_trace]
root 13 0.0 0.0 0 0 ? S 2025 4:48 [ksoftirqd/0]
root 14 0.0 0.0 0 0 ? I 2025 45:30 [rcu_sched]
root 15 0.0 0.0 0 0 ? S 2025 0:20 [migration/0]
root 16 0.0 0.0 0 0 ? S 2025 0:00 [idle_inject/0]
root 18 0.0 0.0 0 0 ? S 2025 0:00 [cpuhp/0]
root 19 0.0 0.0 0 0 ? S 2025 0:00 [cpuhp/1]
root 20 0.0 0.0 0 0 ? S 2025 0:00 [idle_inject/1]
root 21 0.0 0.0 0 0 ? S 2025 0:21 [migration/1]
root 22 0.0 0.0 0 0 ? S 2025 4:35 [ksoftirqd/1]
root 24 0.0 0.0 0 0 ? I< 2025 0:00 [kworker/1:0H-events_highpri]
root 25 0.0 0.0 0 0 ? S 2025 0:00 [kdevtmpfs]
root 26 0.0 0.0 0 0 ? I< 2025 0:00 [inet_frag_wq]
root 28 0.0 0.0 0 0 ? S 2025 0:00 [kauditd]
root 29 0.0 0.0 0 0 ? S 2025 0:02 [khungtaskd]
root 30 0.0 0.0 0 0 ? S 2025 0:00 [oom_reaper]
root 31 0.0 0.0 0 0 ? I< 2025 0:00 [writeback]
root 32 0.0 0.0 0 0 ? S 2025 8:40 [kcompactd0]
root 33 0.0 0.0 0 0 ? SN 2025 0:00 [ksmd]
root 34 0.0 0.0 0 0 ? SN 2025 0:00 [khugepaged]
root 80 0.0 0.0 0 0 ? I< 2025 0:00 [kintegrityd]
root 81 0.0 0.0 0 0 ? I< 2025 0:00 [kblockd]
root 82 0.0 0.0 0 0 ? I< 2025 0:00 [blkcg_punt_bio]
root 83 0.0 0.0 0 0 ? I< 2025 0:00 [tpm_dev_wq]
root 84 0.0 0.0 0 0 ? I< 2025 0:00 [ata_sff]
root 85 0.0 0.0 0 0 ? I< 2025 0:00 [md]
root 86 0.0 0.0 0 0 ? I< 2025 0:00 [edac-poller]
root 87 0.0 0.0 0 0 ? I< 2025 0:00 [devfreq_wq]
root 88 0.0 0.0 0 0 ? S 2025 0:00 [watchdogd]
root 90 0.0 0.0 0 0 ? I< 2025 1:23 [kworker/0:1H-kblockd]
root 91 0.0 0.0 0 0 ? S 2025 2:15 [kswapd0]
root 92 0.0 0.0 0 0 ? S 2025 0:00 [ecryptfs-kthrea]
root 94 0.0 0.0 0 0 ? I< 2025 0:00 [kthrotld]
root 95 0.0 0.0 0 0 ? S 2025 0:00 [irq/51-aerdrv]
root 96 0.0 0.0 0 0 ? S 2025 0:00 [irq/51-pciehp]
root 97 0.0 0.0 0 0 ? S 2025 0:00 [irq/52-aerdrv]
root 98 0.0 0.0 0 0 ? S 2025 0:00 [irq/52-pciehp]
root 99 0.0 0.0 0 0 ? S 2025 0:00 [irq/53-aerdrv]
root 100 0.0 0.0 0 0 ? S 2025 0:00 [irq/53-pciehp]
root 101 0.0 0.0 0 0 ? S 2025 0:00 [irq/54-aerdrv]
root 102 0.0 0.0 0 0 ? S 2025 0:00 [irq/54-pciehp]
root 103 0.0 0.0 0 0 ? S 2025 0:00 [irq/55-aerdrv]
root 104 0.0 0.0 0 0 ? S 2025 0:00 [irq/55-pciehp]
root 105 0.0 0.0 0 0 ? S 2025 0:00 [irq/56-aerdrv]
root 106 0.0 0.0 0 0 ? S 2025 0:00 [irq/56-pciehp]
root 107 0.0 0.0 0 0 ? S 2025 0:00 [irq/57-aerdrv]
root 108 0.0 0.0 0 0 ? S 2025 0:00 [irq/57-pciehp]
root 109 0.0 0.0 0 0 ? S 2025 0:00 [irq/58-aerdrv]
root 110 0.0 0.0 0 0 ? S 2025 0:00 [irq/58-pciehp]
root 111 0.0 0.0 0 0 ? S 2025 0:00 [irq/59-aerdrv]
root 112 0.0 0.0 0 0 ? S 2025 0:00 [irq/59-pciehp]
root 113 0.0 0.0 0 0 ? S 2025 0:00 [irq/49-ACPI:Ged]
root 114 0.0 0.0 0 0 ? I< 2025 0:00 [acpi_thermal_pm]
root 116 0.0 0.0 0 0 ? I< 2025 0:00 [mld]
root 117 0.0 0.0 0 0 ? I< 2025 0:00 [ipv6_addrconf]
root 126 0.0 0.0 0 0 ? I< 2025 0:00 [kstrp]
root 129 0.0 0.0 0 0 ? I< 2025 0:00 [zswap-shrink]
root 130 0.0 0.0 0 0 ? I< 2025 0:00 [kworker/u5:0]
root 134 0.0 0.0 0 0 ? I< 2025 0:00 [cryptd]
root 173 0.0 0.0 0 0 ? I< 2025 0:00 [charger_manager]
root 197 0.0 0.0 0 0 ? I< 2025 1:21 [kworker/1:1H-kblockd]
root 209 0.0 0.0 0 0 ? S 2025 0:03 [hwrng]
root 210 0.0 0.0 0 0 ? S 2025 0:00 [scsi_eh_0]
root 221 0.0 0.0 0 0 ? I< 2025 0:00 [scsi_tmf_0]
root 300 0.0 0.0 0 0 ? I< 2025 0:00 [raid5wq]
root 346 0.0 0.0 0 0 ? S 2025 2:47 [jbd2/sda1-8]
root 347 0.0 0.0 0 0 ? I< 2025 0:00 [ext4-rsv-conver]
root 414 0.0 0.2 67632 8048 ? S<s 2025 7:05 /lib/systemd/systemd-journald
root 448 0.0 0.0 0 0 ? I< 2025 0:00 [kaluad]
root 454 0.0 0.0 0 0 ? I< 2025 0:00 [kmpath_rdacd]
root 455 0.0 0.0 0 0 ? I< 2025 0:00 [kmpathd]
root 456 0.0 0.0 0 0 ? I< 2025 0:00 [kmpath_handlerd]
root 457 0.0 0.6 289888 25700 ? SLsl 2025 8:11 /sbin/multipathd -d -s
root 459 0.0 0.0 10720 2760 ? Ss 2025 0:06 /lib/systemd/systemd-udevd
systemd+ 610 0.0 0.0 88712 1724 ? Ssl 2025 0:07 /lib/systemd/systemd-timesyncd
systemd+ 628 0.0 0.1 16456 4992 ? Ss 2025 0:39 /lib/systemd/systemd-networkd
systemd+ 630 0.0 0.0 26076 3632 ? Ss 2025 0:07 /lib/systemd/systemd-resolved
root 671 0.0 0.0 82124 2620 ? Ssl 2025 6:08 /usr/sbin/irqbalance --foreground
root 677 0.0 0.0 6540 2040 ? Ss 2025 0:08 /usr/sbin/cron -f -P
root 678 0.0 0.0 79464 960 ? Ssl 2025 64:36 /usr/sbin/qemu-ga
syslog 679 0.0 0.1 222044 4080 ? Ssl 2025 1:28 /usr/sbin/rsyslogd -n -iNONE
root 683 0.0 0.1 109620 7304 ? Ssl 2025 20:29 /usr/bin/python3 /usr/share/unattended-upgrades/unattended
root 692 0.1 0.4 1861484 17464 ? Ssl 2025 100:02 /usr/bin/containerd
daemon 698 0.0 0.0 3512 1024 ? Ss 2025 0:00 /usr/sbin/atd -f
root 708 0.0 0.0 5236 436 ttyAMA0 Ss+ 2025 0:00 /sbin/agetty -o -p -- \u --keep-baud 115200,57600,38400,96
root 709 0.0 0.0 5236 432 ttyS0 Ss+ 2025 0:00 /sbin/agetty -o -p -- \u --keep-baud 115200,57600,38400,96
root 712 0.0 0.0 15196 3744 ? Ss 2025 6:43 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
root 713 0.0 0.0 5612 664 tty1 Ss+ 2025 0:00 /sbin/agetty -o -p -- \u --noclear tty1 linux
root 732 0.0 0.7 2488860 30672 ? Ssl 2025 16:37 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/con
systemd+ 955250 0.0 0.5 908900 19820 ? Ss Jan11 0:00 postgres: 15/main: discourse discourse [local] idle
root 978311 0.0 0.0 7064 1608 ? Ss+ Jan11 0:00 bash
root 2844401 0.0 0.0 0 0 ? I Jan28 0:58 [kworker/0:2-events]
root 2919926 0.0 0.0 0 0 ? I 06:00 0:18 [kworker/1:0-events]
root 2929247 0.0 0.0 0 0 ? I 08:03 0:00 [kworker/1:2-events]
root 2947488 0.0 0.0 0 0 ? I 11:58 0:00 [kworker/0:3-events]
root 2958380 0.0 0.0 0 0 ? I 14:18 0:00 [kworker/u4:2-flush-8:0]
systemd+ 2960448 0.2 5.7 928984 224576 ? Ss 14:47 0:16 postgres: 15/main: discourse discourse [local] idle
systemd+ 2966096 0.2 4.1 923428 160800 ? Ss 16:03 0:05 postgres: 15/main: discourse discourse [local] idle
root 2966159 0.0 0.0 0 0 ? I 16:04 0:00 [kworker/u4:3-events_unbound]
root 2966695 0.0 0.0 0 0 ? I 16:11 0:00 [kworker/u4:0-events_unbound]
root 2967455 0.0 0.2 18476 9584 ? Ss 16:21 0:00 sshd: root@pts/0
root 2967537 0.0 0.1 8300 4748 pts/0 Ss 16:21 0:00 -bash
systemd+ 2968782 0.0 3.0 916952 120500 ? Ss 16:35 0:00 postgres: 15/main: discourse discourse [local] idle
systemd+ 2969962 0.0 0.6 908928 23584 ? Ss 16:50 0:00 postgres: 15/main: discourse discourse [local] idle
1000 2969995 0.0 0.0 15928 2824 ? S 16:50 0:00 sleep 1
root 2969996 0.0 0.0 10412 2992 pts/0 R+ 16:50 0:00 ps uax
root 4019702 0.0 0.1 1237968 7740 ? Sl Jan01 4:06 /usr/bin/containerd-shim-runc-v2 -namespace moby -id 6b624
root 4019724 0.0 0.0 6800 324 pts/0 Ss+ Jan01 0:00 /bin/bash /sbin/boot
root 4019750 0.0 0.0 1597212 344 ? Sl Jan01 0:02 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-po
root 4019755 0.0 0.0 1671004 0 ? Sl Jan01 0:02 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 80
root 4019763 0.0 0.0 1671004 1580 ? Sl Jan01 0:02 /usr/bin/docker-proxy -proto tcp -host-ip 0.0.0.0 -host-po
root 4019769 0.0 0.0 1744796 0 ? Sl Jan01 0:02 /usr/bin/docker-proxy -proto tcp -host-ip :: -host-port 44
root 4023771 0.0 0.0 2236 20 pts/0 S+ Jan01 0:35 /usr/bin/runsvdir -P /etc/service
root 4023772 0.0 0.0 2084 0 ? Ss Jan01 0:00 runsv cron
root 4023773 0.0 0.0 2084 0 ? Ss Jan01 0:00 runsv rsyslog
root 4023774 0.0 0.0 2084 8 ? Ss Jan01 0:00 runsv unicorn
root 4023775 0.0 0.0 2084 28 ? Ss Jan01 0:00 runsv nginx
root 4023776 0.0 0.0 2084 0 ? Ss Jan01 0:00 runsv postgres
root 4023777 0.0 0.0 2084 0 ? Ss Jan01 0:00 runsv redis
root 4023778 0.0 0.0 6692 868 ? S Jan01 0:06 cron -f
root 4023779 0.0 0.0 2228 792 ? S Jan01 0:01 svlogd /var/log/postgres
root 4023780 0.0 0.0 54152 2276 ? S Jan01 0:00 nginx: master process /usr/sbin/nginx
systemd+ 4023781 0.0 0.4 905940 19092 ? S Jan01 2:13 /usr/lib/postgresql/15/bin/postmaster -D /etc/postgresql/1
root 4023782 0.0 0.0 152356 208 ? Sl Jan01 0:02 rsyslogd -n
root 4023783 0.0 0.0 2228 836 ? S Jan01 0:02 svlogd /var/log/redis
1000 4023784 0.0 0.0 20592 1664 ? S Jan01 22:38 /bin/bash ./config/unicorn_launcher -E production -c confi
message+ 4023785 0.4 0.6 102368 26700 ? Sl Jan01 165:39 /usr/bin/redis-server *:6379
www-data 4023796 0.1 3.1 188008 124596 ? S Jan01 75:59 nginx: worker process
www-data 4023797 0.1 1.2 98528 49972 ? S Jan01 76:53 nginx: worker process
www-data 4023798 0.0 0.0 54352 1088 ? S Jan01 0:15 nginx: cache manager process
systemd+ 4023807 0.0 8.3 906192 327344 ? Ss Jan01 3:19 postgres: 15/main: checkpointer
systemd+ 4023808 0.0 0.6 906088 24076 ? Ss Jan01 0:24 postgres: 15/main: background writer
systemd+ 4023810 0.0 0.4 905940 18260 ? Ss Jan01 9:48 postgres: 15/main: walwriter
systemd+ 4023811 0.0 0.0 907536 2312 ? Ss Jan01 0:29 postgres: 15/main: autovacuum launcher
systemd+ 4023812 0.0 0.0 907512 2456 ? Ss Jan01 0:01 postgres: 15/main: logical replication launcher
1000 4023813 0.0 3.8 1540732 148552 ? Sl Jan01 7:41 unicorn master -E production -c config/unicorn.conf.rb
systemd+ 4023881 0.0 0.4 919884 16692 ? Ss Jan01 0:03 postgres: 15/main: discourse discourse [local] idle
1000 4024290 1.0 9.4 7103052 368788 ? SNl Jan01 410:25 sidekiq 7.3.9 discourse [0 of 5 busy]
1000 4024313 1.8 10.3 6999048 404032 ? Sl Jan01 728:22 unicorn worker[0] -E production -c config/unicorn.conf.rb
1000 4024339 0.0 9.0 6931980 354124 ? Sl Jan01 37:50 unicorn worker[1] -E production -c config/unicorn.conf.rb
1000 4024397 0.0 7.9 6921672 309392 ? Sl Jan01 14:27 unicorn worker[2] -E production -c config/unicorn.conf.rb
1000 4024478 0.0 6.5 6936200 255776 ? Sl Jan01 12:53 unicorn worker[3] -E production -c config/unicorn.conf.rb
systemd+ 4025084 0.0 1.0 911596 41712 ? Ss Jan01 0:05 postgres: 15/main: discourse discourse [local] idle
systemd+ 4035965 0.0 0.9 908812 35216 ? Ss Jan01 0:38 postgres: 15/main: discourse discourse [local] idle
systemd+ 4044886 0.0 0.8 908812 34968 ? Ss Jan01 0:39 postgres: 15/main: discourse discourse [local] idle
I don’t believe there’s any sensitive data there. If you see something, edit it out before posting!
1 Like
Ed_S
January 29, 2026, 4:56pm
3
I note in the busy times a lot of system kernel time which often means paging. You can always runvmstat 5 5
1 Like
char
January 29, 2026, 5:02pm
4
Thanks, we’ll look into this suggestion.
