Update v25.{1,2,3} AC docs re: short sample setting (#21540)

* Update v25.{1,2} AC docs re: short sample setting

Fixes DOC-15508

Summary of changes, all related to mentions of the `goschedstats.always_use_short_sample_period.enabled` setting:

- Update the v25.1 and v25.2 'Admission Control' pages under the 'Considerations' section to add "To prevent unnecessary queuing in admission control CPU queues, the `goschedstats.always_use_short_sample_period.enabled` setting should be set to `true` for any production cluster."
- Update the v25.1 and v25.2 release notes to add the line to the 'Operational changes' subheading "To prevent unnecessary queuing in admission control CPU queues, the `goschedstats.always_use_short_sample_period.enabled` setting should be set to `true` for any production cluster."
- Update the v25.3 release notes to mention the change in default value of this setting from `false` to `true`

Author: rmloveland

src/current/_includes/releases/v25.1/cluster-setting-changes.md

@@ -47,3 +47,7 @@ The following settings are now marked `public` after previously being `reserved`
 - Removed cluster setting `kv.rangefeed.scheduler.enabled`. The rangefeed scheduler is now unconditionally enabled. [#132825][#132825]
 
 - Removed cluster setting `sql.auth.resolve_membership_single_scan.enabled`. This was added in case it was necessary to revert back to the previous behavior for looking up role memberships, but this cluster setting has not been needed in practice since this was added in v23.1. [#135852][#135852]
+
+<h5 id="v25-1-0-settings-requiring-operational-changes">Settings requiring operational changes</h5>
+
+- To prevent unnecessary queuing in admission control CPU queues, set the `goschedstats.always_use_short_sample_period.enabled` cluster setting to `true` for any production cluster.

src/current/_includes/releases/v25.2/cluster-setting-changes.md

@@ -13,3 +13,7 @@ Changes to [cluster settings]({% link v25.2/cluster-settings.md %}) should be re
 The following settings are now marked `public` after previously being `reserved`. Reserved settings are not documented and their tuning by customers is not supported.
 
 - `sql.stats.detailed_latency_metrics.enabled` - Percentile latencies are no longer available for **SQL Activity**. The implementation of these percentiles was error-prone and difficult to understand because it was computed differently from the other SQL statistics collected. Customers interested in viewing percentile latencies per statement fingerprint are encouraged to use the experimental per-fingerprint histograms that can be enabled with the `sql.stats.detailed_latency_metrics.enabled` cluster setting. This will enable externalized histogram metrics via the Prometheus scrape endpoint. [#139500](https://github.com/cockroachdb/cockroach/pulls/139500)
+
+<h5 id="v25-2-0-settings-requiring-operational-changes">Settings requiring operational changes</h5>
+
+- To prevent unnecessary queuing in admission control CPU queues, set the `goschedstats.always_use_short_sample_period.enabled` cluster setting to `true` for any production cluster.

src/current/_includes/releases/v25.3/cluster-setting-changes.md

@@ -11,8 +11,10 @@ Changes to [cluster settings]({% link v25.3/cluster-settings.md %}) should be re
 
 - The value of `sql.stats.error_on_concurrent_create_stats.enabled` now defaults to `false`, suppressing error counters for auto stats jobs that fail due to concurrent stats jobs in progress. [#149857][#149857]
 - The cluster setting `server.client_cert_expiration_cache.capacity` has been deprecated. The client certificate cache now evicts client certificates based on expiration time. [#144181][#144181]
+- To prevent unnecessary queuing in admission control CPU queues, the `goschedstats.always_use_short_sample_period.enabled` setting default was changed to `true` [#146014][#146014]
 
 [#144181]: https://github.com/cockroachdb/cockroach/pull/144181
 [#144610]: https://github.com/cockroachdb/cockroach/pull/144610
 [#145435]: https://github.com/cockroachdb/cockroach/pull/145435
-[#149857]: https://github.com/cockroachdb/cockroach/pull/149857
+[#146014]: https://github.com/cockroachdb/cockroach/pull/146014
+[#149857]: https://github.com/cockroachdb/cockroach/pull/149857

src/current/v24.1/admission-control.md

@@ -134,6 +134,8 @@ COMMIT;
 
 ## Considerations
 
+To prevent unnecessary queuing in admission control CPU queues, set the `goschedstats.always_use_short_sample_period.enabled` [cluster setting]({% link {{ page.version.version }}/cluster-settings.md %}) to `true` for any production cluster.
+
 [Client connections]({% link {{ page.version.version }}/connection-parameters.md %}) are not managed by the admission control subsystem. Too many connections per [gateway node]({% link {{ page.version.version }}/architecture/sql-layer.md %}#gateway-node) can also lead to cluster overload. 
 
 {% include {{page.version.version}}/sql/server-side-connection-limit.md %}

src/current/v24.3/admission-control.md

@@ -136,6 +136,8 @@ COMMIT;
 
 ## Considerations
 
+To prevent unnecessary queuing in admission control CPU queues, set the `goschedstats.always_use_short_sample_period.enabled` [cluster setting]({% link {{ page.version.version }}/cluster-settings.md %}) to `true` for any production cluster.
+
 [Client connections]({% link {{ page.version.version }}/connection-parameters.md %}) are not managed by the admission control subsystem. Too many connections per [gateway node]({% link {{ page.version.version }}/architecture/sql-layer.md %}#gateway-node) can also lead to cluster overload.
 
 {% include {{page.version.version}}/sql/server-side-connection-limit.md %}

src/current/v25.1/admission-control.md

@@ -154,6 +154,8 @@ COMMIT;
 
 ## Considerations
 
+To prevent unnecessary queuing in admission control CPU queues, the `goschedstats.always_use_short_sample_period.enabled` [cluster setting]({% link {{ page.version.version }}/cluster-settings.md %}) should be set to `true` for any production cluster.
+
 [Client connections]({% link {{ page.version.version }}/connection-parameters.md %}) are not managed by the admission control subsystem. Too many connections per [gateway node]({% link {{ page.version.version }}/architecture/sql-layer.md %}#gateway-node) can also lead to cluster overload.
 
 {% include {{page.version.version}}/sql/server-side-connection-limit.md %}

src/current/v25.2/admission-control.md

@@ -154,6 +154,8 @@ COMMIT;
 
 ## Considerations
 
+To prevent unnecessary queuing in admission control CPU queues, set the `goschedstats.always_use_short_sample_period.enabled` [cluster setting]({% link {{ page.version.version }}/cluster-settings.md %}) to `true` for any production cluster.
+
 [Client connections]({% link {{ page.version.version }}/connection-parameters.md %}) are not managed by the admission control subsystem. Too many connections per [gateway node]({% link {{ page.version.version }}/architecture/sql-layer.md %}#gateway-node) can also lead to cluster overload.
 
 {% include {{page.version.version}}/sql/server-side-connection-limit.md %}