fix(spool): Start spooling at 80% memory utilization#5472
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jjbayer
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Dec 11, 2025
| /// Default max memory usage for unspooling. | ||
| fn spool_max_backpressure_memory_percent() -> f32 { | ||
| 0.9 | ||
| 0.8 |
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I considered not changing the default and only lowering it for SaaS, but
- This will only change behavior for users that have spooling configured and run relay at ~80% memory utilization.
- It might actually benefit self-hosted / managed relay users to switch to more sensible defaults.
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This might be tricky to get right, but since spooling is never enabled by default, users who opt-in will have to make this decision for themselves and 80% also seems like a better threshold for them.
tobias-wilfert
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Dec 11, 2025
Dav1dde
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Dec 11, 2025
| /// Default max memory usage for unspooling. | ||
| fn spool_max_backpressure_memory_percent() -> f32 { | ||
| 0.9 | ||
| 0.8 |
Member
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This might be tricky to get right, but since spooling is never enabled by default, users who opt-in will have to make this decision for themselves and 80% also seems like a better threshold for them.
Co-authored-by: David Herberth <david.herberth@sentry.io>
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The current assumption of the spooler is that it starts spooling at 90% memory utilization, and that memory usage will stabilize before it hits 95%, at which point relay starts failing health checks.
In practice, memory usage keeps growing (at a slower pace) and we almost always become unhealthy.
Lower the default threshold to prevent reaching 95% before utilization stabilizes.
ref: INC-1542