put back feature flag 'delayed-compaction' and 'old-ui' (#14909)

Signed-off-by: Augustin Husson <husson.augustin@gmail.com>

cmd/prometheus/main.go

@@ -471,7 +471,7 @@ func main() {
 	a.Flag("scrape.discovery-reload-interval", "Interval used by scrape manager to throttle target groups updates.").
 		Hidden().Default("5s").SetValue(&cfg.scrape.DiscoveryReloadInterval)
 
-	a.Flag("enable-feature", "Comma separated feature names to enable. Valid options: auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, extra-scrape-metrics, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details.").
+	a.Flag("enable-feature", "Comma separated feature names to enable. Valid options: auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, extra-scrape-metrics, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval, delayed-compaction, old-ui. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details.").
 		Default("").StringsVar(&cfg.featureList)
 
 	a.Flag("agent", "Run Prometheus in 'Agent mode'.").BoolVar(&agentMode)

docs/command-line/prometheus.md

@@ -56,7 +56,7 @@ The Prometheus monitoring server
 | <code class="text-nowrap">--query.timeout</code> | Maximum time a query may take before being aborted. Use with server mode only. | `2m` |
 | <code class="text-nowrap">--query.max-concurrency</code> | Maximum number of queries executed concurrently. Use with server mode only. | `20` |
 | <code class="text-nowrap">--query.max-samples</code> | Maximum number of samples a single query can load into memory. Note that queries will fail if they try to load more samples than this into memory, so this also limits the number of samples a query can return. Use with server mode only. | `50000000` |
-| <code class="text-nowrap">--enable-feature</code> <code class="text-nowrap">...<code class="text-nowrap"> | Comma separated feature names to enable. Valid options: auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, extra-scrape-metrics, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details. |  |
+| <code class="text-nowrap">--enable-feature</code> <code class="text-nowrap">...<code class="text-nowrap"> | Comma separated feature names to enable. Valid options: auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, extra-scrape-metrics, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval, delayed-compaction, old-ui. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details. |  |
 | <code class="text-nowrap">--agent</code> | Run Prometheus in 'Agent mode'. |  |
 | <code class="text-nowrap">--log.level</code> | Only log messages with the given severity or above. One of: [debug, info, warn, error] | `info` |
 | <code class="text-nowrap">--log.format</code> | Output format of log messages. One of: [logfmt, json] | `logfmt` |