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Document default 75% value for GCHeapHardLimitPercent in container environments #50280

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Document default 75% value for GCHeapHardLimitPercent in container environments #50280

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Copilot Dec 2, 2025
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Document default 75% value for GCHeapHardLimitPercent in container en…
Copilot Dec 2, 2025
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Reword GCHeapHardLimitPercent documentation per reviewer feedback
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Reference GCHeapHardLimitPercent section for default value instead of…
Copilot Dec 3, 2025
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4 changes: 2 additions & 2 deletions docs/core/runtime-config/garbage-collector.md
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Expand Up @@ -300,7 +300,7 @@ The following settings apply to all flavors of the GC:

- The heap hard limit is defined as the maximum commit size, in bytes, for the GC heap and GC bookkeeping.
- This setting only applies to 64-bit computers.
- If this limit isn't configured but the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, a default value is set. That default is the greater of 20 MB or 75% of the memory limit on the container.
- If this limit isn't configured but the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, a default value is set. That default is the greater of 20 MB or the [heap hard limit percent](#heap-hard-limit-percent) of the memory limit on the container.
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Copilot AI Dec 3, 2025

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The phrase "the heap hard limit percent of the memory limit on the container" is ambiguous. "Heap hard limit percent" is a setting name, not a value, so this phrasing suggests using a setting name in a calculation. Consider: "That default is the greater of 20 MB or the default percentage from Heap hard limit percent (75%) applied to the memory limit on the container." This clarifies that it's using the default percentage value from that setting.

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- If this limit isn't configured but the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, a default value is set. That default is the greater of 20 MB or the [heap hard limit percent](#heap-hard-limit-percent) of the memory limit on the container.
- If this limit isn't configured but the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, a default value is set. That default is the greater of 20 MB or the default percentage from [Heap hard limit percent](#heap-hard-limit-percent) (75%) applied to the memory limit on the container.

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- This setting is ignored if the [Per-object-heap hard limits](#per-object-heap-hard-limits) are configured.

| | Setting name | Values | Version introduced |
Expand Down Expand Up @@ -339,7 +339,7 @@ The following settings apply to all flavors of the GC:

### Heap hard limit percent

- Specifies the heap hard limit as a percentage of the total physical memory. If the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, the total physical memory is the memory limit; otherwise it's what's available on the machine.
- Specifies the heap hard limit as a percentage of the total physical memory. If the process is running in a memory-constrained environment, that is, inside a container with a specified memory limit, the container limit is considered the total physical memory. If in a memory-constrained environment, the default value is 75%.
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The phrase "If in a memory-constrained environment" is a sentence fragment that creates grammatical confusion. The sentence should be rewritten for clarity. Consider: "When in a memory-constrained environment and this setting isn't explicitly configured, the default value is 75%." This provides better flow and clarifies that 75% is the default when the setting is not specified.

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- This setting only applies to 64-bit computers.
- This setting is ignored if the [Per-object-heap hard limits](#per-object-heap-hard-limits) are configured or the [heap hard limit](#heap-hard-limit) is configured.

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