mirror of
https://github.com/coder/coder.git
synced 2025-07-12 00:14:10 +00:00
docs: add documentation for prebuild scheduling feature (#18462)
Follow-up to https://github.com/coder/coder/pull/18126 Changes: - address issue mentioned here: https://github.com/coder/coder/pull/18126#discussion_r2144557600 - add docs for prebuilds scheduling --------- Co-authored-by: Danny Kopping <danny@coder.com> Co-authored-by: Atif Ali <atif@coder.com>
This commit is contained in:
committed by
GitHub
parent
da5d5ba96a
commit
8e3022ed9e
@ -12,6 +12,7 @@ Prebuilt workspaces are:
|
||||
- Created and maintained automatically by Coder to match your specified preset configurations.
|
||||
- Claimed transparently when developers create workspaces.
|
||||
- Monitored and replaced automatically to maintain your desired pool size.
|
||||
- Automatically scaled based on time-based schedules to optimize resource usage.
|
||||
|
||||
## Relationship to workspace presets
|
||||
|
||||
@ -111,6 +112,105 @@ prebuilt workspace can remain before it is considered expired and eligible for c
|
||||
Expired prebuilt workspaces are removed during the reconciliation loop to avoid stale environments and resource waste.
|
||||
New prebuilt workspaces are only created to maintain the desired count if needed.
|
||||
|
||||
### Scheduling
|
||||
|
||||
Prebuilt workspaces support time-based scheduling to scale the number of instances up or down.
|
||||
This allows you to reduce resource costs during off-hours while maintaining availability during peak usage times.
|
||||
|
||||
Configure scheduling by adding a `scheduling` block within your `prebuilds` configuration:
|
||||
|
||||
```tf
|
||||
data "coder_workspace_preset" "goland" {
|
||||
name = "GoLand: Large"
|
||||
parameters {
|
||||
jetbrains_ide = "GO"
|
||||
cpus = 8
|
||||
memory = 16
|
||||
}
|
||||
|
||||
prebuilds {
|
||||
instances = 0 # default to 0 instances
|
||||
|
||||
scheduling {
|
||||
timezone = "UTC" # only a single timezone may be used for simplicity
|
||||
|
||||
# scale to 3 instances during the work week
|
||||
schedule {
|
||||
cron = "* 8-18 * * 1-5" # from 8AM-6:59PM, Mon-Fri, UTC
|
||||
instances = 3 # scale to 3 instances
|
||||
}
|
||||
|
||||
# scale to 1 instance on Saturdays for urgent support queries
|
||||
schedule {
|
||||
cron = "* 8-14 * * 6" # from 8AM-2:59PM, Sat, UTC
|
||||
instances = 1 # scale to 1 instance
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
**Scheduling configuration:**
|
||||
|
||||
- **`timezone`**: The timezone for all cron expressions (required). Only a single timezone is supported per scheduling configuration.
|
||||
- **`schedule`**: One or more schedule blocks defining when to scale to specific instance counts.
|
||||
- **`cron`**: Cron expression interpreted as continuous time ranges (required).
|
||||
- **`instances`**: Number of prebuilt workspaces to maintain during this schedule (required).
|
||||
|
||||
**How scheduling works:**
|
||||
|
||||
1. The reconciliation loop evaluates all active schedules every reconciliation interval (`CODER_WORKSPACE_PREBUILDS_RECONCILIATION_INTERVAL`).
|
||||
2. The schedule that matches the current time becomes active. Overlapping schedules are disallowed by validation rules.
|
||||
3. If no schedules match the current time, the base `instances` count is used.
|
||||
4. The reconciliation loop automatically creates or destroys prebuilt workspaces to match the target count.
|
||||
|
||||
**Cron expression format:**
|
||||
|
||||
Cron expressions follow the format: `* HOUR DOM MONTH DAY-OF-WEEK`
|
||||
|
||||
- `*` (minute): Must always be `*` to ensure the schedule covers entire hours rather than specific minute intervals
|
||||
- `HOUR`: 0-23, range (e.g., 8-18 for 8AM-6:59PM), or `*`
|
||||
- `DOM` (day-of-month): 1-31, range, or `*`
|
||||
- `MONTH`: 1-12, range, or `*`
|
||||
- `DAY-OF-WEEK`: 0-6 (Sunday=0, Saturday=6), range (e.g., 1-5 for Monday to Friday), or `*`
|
||||
|
||||
**Important notes about cron expressions:**
|
||||
|
||||
- **Minutes must always be `*`**: To ensure the schedule covers entire hours
|
||||
- **Time ranges are continuous**: A range like `8-18` means from 8AM to 6:59PM (inclusive of both start and end hours)
|
||||
- **Weekday ranges**: `1-5` means Monday through Friday (Monday=1, Friday=5)
|
||||
- **No overlapping schedules**: The validation system prevents overlapping schedules.
|
||||
|
||||
**Example schedules:**
|
||||
|
||||
```tf
|
||||
# Business hours only (8AM-6:59PM, Mon-Fri)
|
||||
schedule {
|
||||
cron = "* 8-18 * * 1-5"
|
||||
instances = 5
|
||||
}
|
||||
|
||||
# 24/7 coverage with reduced capacity overnight and on weekends
|
||||
schedule {
|
||||
cron = "* 8-18 * * 1-5" # Business hours (8AM-6:59PM, Mon-Fri)
|
||||
instances = 10
|
||||
}
|
||||
schedule {
|
||||
cron = "* 19-23,0-7 * * 1,5" # Evenings and nights (7PM-11:59PM, 12AM-7:59AM, Mon-Fri)
|
||||
instances = 2
|
||||
}
|
||||
schedule {
|
||||
cron = "* * * * 6,0" # Weekends
|
||||
instances = 2
|
||||
}
|
||||
|
||||
# Weekend support (10AM-4:59PM, Sat-Sun)
|
||||
schedule {
|
||||
cron = "* 10-16 * * 6,0"
|
||||
instances = 1
|
||||
}
|
||||
```
|
||||
|
||||
### Template updates and the prebuilt workspace lifecycle
|
||||
|
||||
Prebuilt workspaces are not updated after they are provisioned.
|
||||
@ -195,12 +295,6 @@ The prebuilt workspaces feature has these current limitations:
|
||||
|
||||
[View issue](https://github.com/coder/internal/issues/364)
|
||||
|
||||
- **Autoscaling**
|
||||
|
||||
Prebuilt workspaces remain running until claimed. There's no automated mechanism to reduce instances during off-hours.
|
||||
|
||||
[View issue](https://github.com/coder/internal/issues/312)
|
||||
|
||||
### Monitoring and observability
|
||||
|
||||
#### Available metrics
|
||||
|
Reference in New Issue
Block a user