[v3-3-test] Honor the API server Dag cache TTL when no size limit is set (#71814) by jason810496 · Pull Request #71845 · apache/airflow

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 · 2026-08-19T15:39:51Z

Setting [api] dag_cache_size = 0 was meant to mean "no size limit," but it silently disabled TTL-based eviction too, ignoring dag_cache_ttl entirely.

Now the TTL applies regardless of size limit, and eviction is only fully disabled when both dag_cache_size and dag_cache_ttl are 0. Deployments using dag_cache_size = 0 will start evicting on the default one-hour TTL; set dag_cache_ttl = 0 to keep the old behavior.

Also included:

negative dag_cache_size/dag_cache_ttl values now raise a ValueError instead of being silently clamped (validated both at the API config boundary and defensively in DBDagBag)
docs are corrected to show these options shipped in 3.2.2, not 3.3.0, with clarified wording on when TTL refreshes actually happen.

(cherry picked from commit f63d321)

…set (apache#71814) * Honor the API server Dag cache TTL when no size limit is set `[api] dag_cache_size = 0` reads as "no size limit", but it selected a mapping that never evicted at all and silently ignored `[api] dag_cache_ttl`. Age-based eviction could therefore only be enabled by also accepting a size cap, which is backwards for a deployment that wants to bound staleness rather than count. A TTL now applies with or without a size limit, and only setting both options to 0 disables eviction. Deployments on `dag_cache_size = 0` start evicting on the default hour-long TTL; setting `dag_cache_ttl = 0` restores the old behaviour. The options were also documented as added in 3.3.0. They shipped in 3.2.2. * Reject negative API Dag cache values and clarify TTL behavior Negative cache configuration should fail fast, and operator guidance must reflect that TTL refreshes happen only at revalidation boundaries. * Reject negative cache values for every DBDagBag caller Validating at the shared boundary prevents non-API callers from silently clamping invalid cache settings. * Clarify cache validation context and docs wording Context-specific errors help operators identify invalid API settings, while defensive constructor checks protect other callers and documentation remains compatible with the spellchecker. * Clarify API cache TTL documentation layout (cherry picked from commit f63d321) Co-authored-by: Jason(Zhe-You) Liu <68415893+jason810496@users.noreply.github.com>

jason810496 requested review from XD-DENG, ashb, bugraoz93, choo121600, ephraimbuddy, henry3260, pierrejeambrun, rawwar and shubhamraj-git as code owners August 19, 2026 15:39

jason810496 self-assigned this Aug 19, 2026

boring-cyborgBot added area:API Airflow's REST/HTTP API area:ConfigTemplates kind:documentation labels Aug 19, 2026