Very slow energy dashboard

Vicolaships · November 18, 2025, 10:51am

Hello,

The energy dashboard takes more than a minute to display the bar graphs and every-time I switch month/day the loading takes 1 minutes again. Everything else is very responsive.

I’m using a Raspberry Pi 5 with NVME disk as the host. It is a docker install:

$ cat docker-compose.yml 
services:
  homeassistant:
    container_name: homeassistant
    image: ghcr.io/home-assistant/home-assistant:stable
    volumes:
      - /home/victor/homeassistant:/config
      - /etc/localtime:/etc/localtime:ro
    ports:
      - 8123:8123
    restart: unless-stopped
    group_add:
      - dialout
    network_mode: host
    devices:
      - /dev/ttyUSB0:/dev/ttyUSB0  # USB access via groups

I’m using a recent docker image:

Méthode d'installation Home Assistant Container
Core 2025.10.4
Interface utilisateur 20251001.4

The energy dashboard only contains about 30 days of data (new install). One CPU is running at 100% when the energy dashboard is loading and CPU usage drops to 0% after data is loaded in the web page.

Loads for about 1 minute then shows data as expected:

How can I debug this and solve this issue?

Thank you

Impact · November 18, 2025, 11:11am

Did you modify the recorder settings? What’s top -co%CPU showing during the 100% usage?

IOT7712 · November 18, 2025, 2:47pm

How much data is it analyzing to display?
Are you recording consumption for each nanosecond, or default settings?
How large is your database?
How much memory does your Pi have?

Vicolaships · November 18, 2025, 4:25pm

Here is my configuration:

$ cat configuration.yaml 
# Loads default set of integrations. Do not remove.
default_config:

http:
  # For extra security set this to only accept connections on localhost if NGINX is on the same machine
  # Uncommenting this will mean that you can only reach Home Assistant using the proxy, not directly via IP from other clients.
  #  server_host: 172.18.0.1
  use_x_forwarded_for: true
  # You must set the trusted proxy IP address so that Home Assistant will properly accept connections
  # Set this to your NGINX machine IP, or localhost if hosted on the same machine.
  trusted_proxies:
    - 127.0.0.1
    - 172.18.0.1
    - 192.168.1.2

automation: !include automations.yaml
script: !include scripts.yaml
scene: !include scenes.yaml

input_boolean:
  air_heater:
    name: Chauffage air VMC
    icon: mdi:hvac

alarm_control_panel:
  - platform: manual
    code_arm_required: false
    delay_time: 0
    arming_states: armed_away

frontend:
  themes:
    "Energy: Tempo colors":
      modes:
        light:
          energy-grid-consumption-color-0: "#6a9aad"
          energy-grid-consumption-color-1: "#039DE0"
          energy-grid-consumption-color-2: "#C8D9E5"
          energy-grid-consumption-color-3: "#8BAAC0"
          energy-grid-consumption-color-4: "#F49D9A"
          energy-grid-consumption-color-5: "#D9534F"
          energy-grid-consumption-color-6: "#9eb75C"
        dark:
          energy-grid-consumption-color-0: "#9BE1FD"
          energy-grid-consumption-color-1: "#039DE0"
          energy-grid-consumption-color-2: "#C8D9E5"
          energy-grid-consumption-color-3: "#8BAAC0"
          energy-grid-consumption-color-4: "#F49D9A"
          energy-grid-consumption-color-5: "#D9534F"
          energy-grid-consumption-color-6: "#9eb75C"

Here is the top process:

    PID USER      PR  NI    VIRT    RES    SHR S  %CPU  %MEM     TIME+ COMMAND     
 131003 root      20   0 1185860 491292 105216 S 100,3   6,0  21:03.86 python3 -m homeassistant --config /config

Next process in the list uses less than 1% of a CPU.

Default energy dashboard view is 1 month but I get the same result for 1 day
Consumption are recorded with the default settings
1 month of data
My Pi has 8 Gb of memory, it’s not a bottleneck here:

$ free -m
               total        used        free      shared  buff/cache   available
Mem:            7937        1120        3628          76        3451        6816
Swap:           1023           0        1023

IOT7712 · November 18, 2025, 5:14pm

I’m guessing it does a fresh database query in real time each time your dashboard loads, as well as refreshes, and this takes about a minute as you have observed. Consider how many stored date points are being queried from all of your visible six sources in the display, it is probably about right. Database query optimization may be in your future - see the source code in GitHub for clues

Vicolaships · November 18, 2025, 7:49pm

This can’t be right. I can load the history panel with many sensors (thousands of points) and it is close to instantaneous.

A simple query like that on the database shouldn’t take more than a second.

Vicolaships · November 22, 2025, 2:01pm

Does anyone have insight on the problem?

okaufmann · January 14, 2026, 4:22pm

I have the same Problem. Loading the Energy Dashboard takes several seconds (often 30-60). My HA runs on a VM with enough resources on a solid Game PC. This seems to be a performance problem loading history data.

I am using the MariaDB Add-On for the DB.

Vicolaships · January 27, 2026, 10:56am

I’m bringing back this issue as I’ve not found any solution to this problem.
I do not seem to be alone with this issue, energy dashboard is unusable as is for us.

Can someone give us instructions on what information we should provide for a bug report?

Thanks

misenko · February 6, 2026, 9:06pm

Hi guys, I have the same issue but I guess it’s related to MariaDB. Thing is, before I was using SD card but after a year it was destroyed so I’ve bough NVMe SSD drive instead. Installed today and decided to switch from sqlite to MariaDB at the same time because it’s usually more reliable and should be faster. It was pain to migrate, DB had around 20GB. At the end I’ve managed to do it and noticed that energy dashboard loads much much slower. Even one day takes 10 - 15 second. Strange is that monthly stats takes the same time. Everything else is snappy an fast. Sadly, at the same time I also upgraded to this 2026 version of hassio os and core so I can’t definitely tell if it’s related to MariaDB or migration to 2026. I must say that I absolutely don’t like the new energy dashboard with that floating datepicker and new division into tabs summary, energy, gass etc… It’s horrible…

There is no way it is that slower with SSD drive then it was with SD card. I will rollback it back to sqlite and try it again because this is not normal. I’ve spent a whole day with this shit and I’m pretty exhausted.

checking12 · February 6, 2026, 9:12pm

mariado has tuning options for this. after tuning it’s way faster

See Improve Your Home Assistant Performance with MariaDB Tuning - #13 by jmrplens