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diff --git a/src/mongo/db/query/telemetry_util.h b/src/mongo/db/query/telemetry_util.h
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+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include "mongo/base/status.h"
+#include "mongo/db/concurrency/d_concurrency.h"
+#include "mongo/db/query/partitioned_cache.h"
+#include "mongo/db/query/util/memory_util.h"
+
+
+namespace mongo::telemetry_util {
+
+Status onTelemetryStoreSizeUpdate(const std::string& str);
+
+
+Status validateTelemetryStoreSize(const std::string& str, const boost::optional<TenantId>&);
+
+Status onTelemetrySamplingRateUpdate(int samplingRate);
+
+/**
+ *  An interface used to modify the telemetry store when query setParameters are modified. This is
+ *  done via an interface decorating the 'ServiceContext' in order to avoid a link-time dependency
+ *  of the query knobs library on the telemetry code.
+ */
+class OnParamChangeUpdater {
+public:
+    virtual ~OnParamChangeUpdater() = default;
+
+    /**
+     * Resizes the telemetry store decorating 'serviceCtx' to the new size given by 'memSize'. If
+     * the new size is smaller than the old, cache entries are evicted in order to ensure the
+     * cache fits within the new size bound.
+     */
+    virtual void updateCacheSize(ServiceContext* serviceCtx, memory_util::MemorySize memSize) = 0;
+
+    /**
+     * Updates the sampling rate for the telemetry rate limiter.
+     */
+    virtual void updateSamplingRate(ServiceContext* serviceCtx, int samplingRate) = 0;
+};
+
+/**
+ * A stub implementation that does not allow changing any parameters - to be used if the telemetry
+ * store is disabled and cannot be re-enabled without restarting, as with a feature flag.
+ */
+class NoChangesAllowedTelemetryParamUpdater : public OnParamChangeUpdater {
+public:
+    void updateCacheSize(ServiceContext* serviceCtx, memory_util::MemorySize memSize) final {
+        uasserted(7373500,
+                  "Cannot configure telemetry store - it is currently disabled and a restart is "
+                  "required to activate.");
+    }
+
+    void updateSamplingRate(ServiceContext* serviceCtx, int samplingRate) {
+        uasserted(7506200,
+                  "Cannot configure telemetry store - it is currently disabled and a restart is "
+                  "required to activate.");
+    }
+};
+
+/**
+ * Decorated accessor to the 'OnParamChangeUpdater' stored in 'ServiceContext'.
+ */
+extern const Decorable<ServiceContext>::Decoration<std::unique_ptr<OnParamChangeUpdater>>
+    telemetryStoreOnParamChangeUpdater;
+}  // namespace mongo::telemetry_util