# Discourse unavailable with high load average
**URL:** https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246
**Category:** Support
**Created:** [September 3, 2018, 7:33am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246 "2018-09-03T07:33:47Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 7:33am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/1 "2018-09-03T07:33:47Z")
Hello everyone,
I have been running an instance of Discourse for the last 2 years with Digital Ocean without any problem but since the last 2 weeks, it became very slow or unavailable most of the time.
I have upgraded my hosting to the following one, it’s a bit better but still facing the same problems:
- Ubuntu 14.04 x64
- 2 vCPUs
- 4GB / 80GB Disk
This is the output of the **htop** command:
Any idea where to start fixing this problem? Thanks a lot for your help.
---
### Author:  [@mpalmer](https://meta.discourse.org/u/mpalmer)
#### Post date: [September 3, 2018, 8:38am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/2 "2018-09-03T08:38:59Z")
What’s the %iowait? In general, `htop` is a poor substitute for `top` for actual diagnostic purposes.
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 8:42am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/3 "2018-09-03T08:42:30Z")
```plaintext
top - 04:41:15 up 1 day, 25 min, 1 user, load average: 6.32, 7.70, 6.89
Tasks: 162 total, 4 running, 158 sleeping, 0 stopped, 0 zombie
%Cpu(s): 64.2 us, 19.9 sy, 0.0 ni, 6.9 id, 7.7 wa, 0.0 hi, 1.3 si, 0.0 st
KiB Mem : 4048268 total, 116444 free, 2742964 used, 1188860 buff/cache
KiB Swap: 1048572 total, 451544 free, 597028 used. 68040 avail Mem
```
---
### Author:  [@mpalmer](https://meta.discourse.org/u/mpalmer)
#### Post date: [September 3, 2018, 8:49am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/4 "2018-09-03T08:49:10Z")
Given the 1m load average is nearly half what it was in the previous screenshot, and %iowait is still pretty high, I’d say you’re probably I/O constrained, likely due to swapping. Confirm with `sar -W 1` whilst the system is at peak unhappiness, and then upgrade RAM.
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 8:54am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/5 "2018-09-03T08:54:11Z")
Thanks Matt,
Here is the output of the `sar -W 1` (I have no idea what it is 😕 )
```plaintext
04:52:49 AM pswpin/s pswpout/s
04:52:50 AM 95.00 2.00
04:52:51 AM 166.00 0.00
04:52:52 AM 40.00 0.00
04:52:53 AM 19.00 0.00
04:52:54 AM 74.00 0.00
04:52:55 AM 125.00 0.00
04:52:56 AM 247.00 0.00
04:52:57 AM 215.84 2.97
04:52:58 AM 70.00 0.00
04:52:59 AM 334.00 0.00
04:53:00 AM 390.00 0.00
04:53:01 AM 568.00 6.00
04:53:02 AM 702.00 0.00
04:53:03 AM 1047.52 5.94
04:53:04 AM 416.00 0.00
04:53:05 AM 449.00 0.00
04:53:06 AM 691.00 0.00
04:53:07 AM 772.00 6.00
04:53:08 AM 550.00 0.00
04:53:09 AM 181.00 0.00
04:53:10 AM 476.00 0.00
04:53:11 AM 348.00 0.00
04:53:12 AM 316.00 4.00
04:53:13 AM 454.00 0.00
04:53:14 AM 356.00 0.00
04:53:15 AM 911.88 7.92
04:53:16 AM 262.00 0.00
04:53:17 AM 303.00 0.00
04:53:18 AM 271.00 0.00
04:53:19 AM 284.00 6.00
```
---
### Author:  [@mpalmer](https://meta.discourse.org/u/mpalmer)
#### Post date: [September 3, 2018, 9:06am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/6 "2018-09-03T09:06:58Z")
The headings should give you a hint… “pages swapped in per second” and “pages swapped out per second”. Each page is (usually) 4k, so swapping in 1,000 pages in a second means you’re copying about 4MB of data off disk and into RAM. That’s gonna take a while.
You’re definitely due for a RAM upgrade, or doing something to reduce RAM usage (although your unicorns aren’t exactly sitting around chatting over the sports page, so I wouldn’t recommend that).
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [September 3, 2018, 9:10am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/7 "2018-09-03T09:10:01Z")
Running this many unicorn workers on two virtual cpus that already run redis and pg does not make sense.
I would run 3 workers max, and give the leftover ram to postgres.
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 9:17am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/8 "2018-09-03T09:17:54Z")
Thanks guys.
What I don’t understand is that I had 2GB RAM and it was working well, then suddenly I started to have a high load average. I already upgraded to 4GB RAM and I am still facing the same issue, how is it possible that Discourse suddenly needs so much more RAM?
I also changed my `app.yml` with `UNICORN_WORKERS: 3`, it was 8 before.
I am rebuilding the app now and I’ll check if there is any changes.
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [September 3, 2018, 9:18am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/9 "2018-09-03T09:18:38Z")
> [@JohnDoux](#):
>
> I also changed my `app.yml` with `UNICORN_WORKERS: 3` , it was 8 before.
let us know how you go with the safer number
---
### Author:  [@mpalmer](https://meta.discourse.org/u/mpalmer)
#### Post date: [September 3, 2018, 9:23am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/10 "2018-09-03T09:23:19Z")
> [@JohnDoux](#):
>
> how is it possible that Discourse suddenly needs so much more RAM?
You probably started serving a whole lot more traffic.
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 10:13am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/11 "2018-09-03T10:13:38Z")
> [@mpalmer](#):
>
> You probably started serving a whole lot more traffic.
Well actually that’s pretty much the opposite 😕 It’s a lot more quiet during summer vacation.
So after 2 hours and around 30 users live:
```plaintext
top - 06:11:09 up 1 day, 1:55, 1 user, load average: 4.09, 3.24, 2.91
Tasks: 130 total, 7 running, 123 sleeping, 0 stopped, 0 zombie
%Cpu(s): 62.5 us, 26.4 sy, 0.0 ni, 1.4 id, 7.4 wa, 0.0 hi, 2.3 si, 0.0 st
KiB Mem : 4048268 total, 135872 free, 1739644 used, 2172752 buff/cache
KiB Swap: 1048572 total, 975084 free, 73488 used. 1763862 avail Mem
```
```plaintext
06:12:12 AM pswpin/s pswpout/s
06:12:13 AM 0.00 0.00
06:12:14 AM 0.00 0.00
06:12:15 AM 0.00 0.00
06:12:16 AM 0.00 0.00
06:12:17 AM 0.00 0.00
06:12:18 AM 0.00 0.00
06:12:19 AM 0.00 0.00
06:12:20 AM 0.00 0.00
06:12:21 AM 0.00 0.00
06:12:22 AM 0.00 0.00
06:12:23 AM 0.00 6.00
06:12:24 AM 0.00 0.00
06:12:25 AM 0.00 0.00
06:12:26 AM 0.00 0.00
06:12:27 AM 0.00 5.00
06:12:28 AM 0.00 0.00
06:12:29 AM 0.00 0.00
```
It’s still super slow, and I keep having errors 502 on my side when I try answering a message. Some messages can be posted though.
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [September 3, 2018, 11:03am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/12 "2018-09-03T11:03:53Z")
How many page views are you getting? Where is the traffic coming from? Look at you nginx logs, maybe your server is under some sort of attack
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 1:10pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/13 "2018-09-03T13:10:43Z")
I am having around 20 to 30 page views/minute, around 30 users at the same time.
I am checking the nginx log but not sure how to analyse all those stuffs, I checked that script but seems to be deprecated? [Analyze Discourse performance using NGINX logs](https://meta.discourse.org/t/analyzing-discourse-performance-using-nginx-logs/30117)
I also checked the [Post-Install Maintenance](https://github.com/discourse/discourse/blob/master/docs/INSTALL-cloud.md#post-install-maintenance) section and did a `apt-get install fail2ban`, I am not sure if I have to do anything else but it seems to decrease slightly the load average.
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [September 3, 2018, 3:01pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/14 "2018-09-03T15:01:39Z")
I recently had similar problems that went away when I switched to an “optimized” droplet.
---
### Author:  [@JohnDoux](https://meta.discourse.org/u/JohnDoux)
#### Post date: [September 3, 2018, 4:23pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/15 "2018-09-03T16:23:33Z")
Yeah but it’s 5 times more expensive for the size of the disk I need 😕 I unfortunately cannot afford it 😕
---
### Author:  [@pfaffman](https://meta.discourse.org/u/pfaffman)
#### Post date: [September 3, 2018, 10:37pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/16 "2018-09-03T22:37:10Z")
My solution was to move backups and uploads to wherever digital ocean Volumes ($10/month for 100GB).
---
### Author:  [@merefield](https://meta.discourse.org/u/merefield)
#### Post date: [September 4, 2018, 9:07am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/19 "2018-09-04T09:07:12Z")
> [@JohnDoux](#):
>
> Yeah but it’s 5 times more expensive for the size of the disk I need 😕 I unfortunately cannot afford it 😕
Then shop around 🛒 🙂 . Look at Vultr, Scaleway, Hetzner …
---
### Author:  [@ssvenn](https://meta.discourse.org/u/ssvenn)
#### Post date: [September 4, 2018, 5:43pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/20 "2018-09-04T17:43:04Z")
I know this is kinda besides the point now but I want to post in defense of htop that you can enable advanced CPU stats to get the iowait stats and add process state, IO read and write bytes to get a better picture at what processes eat a lot of IO ( [https://serverfault.com/questions/848714/htop-show-i-o-wait-percentage](https://serverfault.com/questions/848714/htop-show-i-o-wait-percentage) )
There’s also a giant list of other optional columns like page faults to play around with in the F2 setup menu 🙂
---
### Author:  [@mpalmer](https://meta.discourse.org/u/mpalmer)
#### Post date: [September 4, 2018, 11:47pm UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/21 "2018-09-04T23:47:35Z")
Let me know when you figure out how to use the F2 setup menu in a screenshot.
---
### Author:  [@ssvenn](https://meta.discourse.org/u/ssvenn)
#### Post date: [September 5, 2018, 5:59am UTC](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246/22 "2018-09-05T05:59:58Z")
Oof, that 30 second length limit on imgur animations is brutal
(using OBS and keycastr in case that’s interesting)
[Next page](https://meta.discourse.org/t/discourse-unavailable-with-high-load-average/96246.md?page=2)