Oh Robert,
We migrate to a new vps with 4 core(Ryzen 9 5950x),
Cpu usage is still almost 100%. I really don’t know what is wrong.
I thought you were going to move to an 8 core Scaleway server?
What is the claimed bandwidth of this server? I wonder if low bandwidth could cause slow connections/disconnections to become a bottleneck?
Scaleway have VPS with bandwidths of hundreds of megabits per second, not 30.
30 seems extremely low to me.
This is the spec.
4096MB DDR3 ECC RAM
4 CPU vCores (3.4+ GHz E3-1231 v3/1241 v3/1240 v5)
200GB Raid 10 HDD Storage
5TB bandwidth @ 1Gb/s (speed limited to 5Mb/s after allocation used)
1 IPv4, /64 IPv6
20Gb/s TCP DDoS Protection, 200Gb/s upgrade available
Seattle, Washington, US
Virtualizor Control Panel
Unmanaged
Because of time delay, we finally chose this cloud service provider. They did the optimization of the network for visitors from our country.
By the way, output of htop is
100% CPU usage is abnormal.
Everything is fine except load and cpu usage.
Anything strange in access logs?
Oh now it seems like it is calming down now.
We guess restoring from a backup causes a spike in cpu usage.
Anyway, thank you very much Robert!
2 Likes
Oh yes that would do it!
Hum, you should aim for ssd
2 Likes
Good catch Benjamin!
Scaleway and others have NVMe SSDs. Much better!
CPU could be waiting on disk.
1 Like
oh sorry I just pasted a wrong spec.
The spec is
4096MB DDR4 ECC RAM
4 CPU vCores (3.4GHz AMD Ryzen 5950X)
100GB Raid NVMe SSD Storage
5TB bandwidth @ 10Gb/s (speed limited to 5Mb/s after allocation used)
1 IPv4, /64 IPv6
20Gb/s TCP DDoS Protection, 200Gb/s upgrade available
Seattle, Washington, US
Virtualizor Control Panel
Unmanaged
It is NVMe. 
3 Likes
I think it is possible the plugins we installed have increased the load.
The plugin made such a change to the user model that when we go to discovery route, we always calculate the points of user model in topic model for many times
add_to_class(:user, :total_earned_points) do
self.user_points.sum(:reward_points)
end
add_to_class(:user, :available_points) do
self.total_earned_points - self.user_rewards.sum(:points)
end
add_to_class(:user, :rewards) do
DiscourseRewards::Reward.where(created_by_id: self.id)
end
add_to_serializer(:basic_user, :total_earned_points) do
user&.total_earned_points
end
add_to_serializer(:basic_user, :available_points) do
user&.available_points
end
add_to_serializer(:current_user, :total_earned_points) do
scope.user.total_earned_points
end
add_to_serializer(:current_user, :available_points) do
scope.user.available_points
end
add_to_serializer(:current_user, :user_rewards) do
scope.user.user_rewards
end
add_to_serializer(:current_user, :rewards) do
scope.user.rewards
end
I thought you’d said you’d removed all plugins and it was behaving the same?
Does this have an index?
How many rows is user_rewards table? Interesting it is not distinguishing by user … (but I assume it must be somehow beneath this level).
Oh I am afraid it doesn’t set an index.
The model is shown below.
module DiscourseRewards
class Reward < ActiveRecord::Base
self.table_name = 'discourse_rewards_rewards'
has_many :user_rewards
belongs_to :created_by, class_name: 'User'
default_scope { where(deleted_at: nil) }
end
end
module DiscourseRewards
class UserPoint < ActiveRecord::Base
self.table_name = 'discourse_rewards_user_points'
belongs_to :user
belongs_to :user_badge
belongs_to :user_points_category
def self.user_total_points(user)
UserPoint.where(user_id: user.id).sum(:reward_points)
end
end
end
module DiscourseRewards
class UserReward < ActiveRecord::Base
self.table_name = 'discourse_rewards_user_rewards'
belongs_to :user
belongs_to :reward
enum status: [:applied, :granted]
end
end
I disable all plugin on safe mode. However you know, the database didn’t change. 
Something to take up with the author I suspect.
Looks like it might not be scaling for your high number of users?
You may need to rebuild without the plugin. It would be a good comparison and maybe confirm if the issues are caused by the plugin or not.
The presence of tables won’t matter if the queries aren’t running.
2 Likes
discourse_rewards_user_points | 233525 | 27 MB | 5152 kB | 32 MB
discourse_rewards_user_rewards | 61 | 16 kB | 16 kB | 32 kB
discourse_rewards_user_points_categories | 9 | 16 kB | 16 kB | 32 kB
discourse_rewards_rewards | 4 | 16 kB | 16 kB | 32 kB
discourse_rewards_user_points table is huge.
1 Like
Completely remove it (from build, no need to destroy the tables), see what happens.
2 Likes
Thank you, I 'll try it right now.
1 Like
Oh Robert, I rebuild without the plugin, response time for pages of discovery route is reduced to less than 200ms from 2-3s before.
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Well there you have it. I would discuss optimisation with the author, or if you have the skills, PR?
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I am asking for our friend who is familiar with database for help.
But he is working on JAVA. I think it will takes some time.
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