[GitHub] [ignite] nizhikov commented on a change in pull request #6627: IGNITE-11925: QueryMetrics migration.

[GitBox <gi...@apache.org>]

nizhikov commented on a change in pull request #6627: IGNITE-11925: QueryMetrics migration.
URL: https://github.com/apache/ignite/pull/6627#discussion_r297688915
 
 

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 File path: modules/core/src/main/java/org/apache/ignite/internal/processors/metric/impl/MetricUtils.java
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 @@ -83,6 +83,32 @@ public static boolean compareAndSet(LongMetricImpl m, long expect, long update)
         return LongMetricImpl.updater.compareAndSet(m, expect, update);
     }
 
+    /**
+     * Update metrics value only if current value if less then {@code update}.
+     *
+     * @param m Metric to update.
+     * @param update New value.
+     */
+    public static void setIfLess(LongMetricImpl m, long update) {
+        long v = m.value();
+
+        while (v > update && !LongMetricImpl.updater.compareAndSet(m, v, update))
+            v = m.value();
+    }
+
+    /**
+     * Update metrics value only if current value if greater then {@code update}.
+     *
+     * @param m Metric to update.
+     * @param update New value.
+     */
+    public static void setIfGreater(LongMetricImpl m, long update) {
+        long v = m.value();
+
+        while (v < update && !LongMetricImpl.updater.compareAndSet(m, v, update))
 
 Review comment:
   Proposed implementation is less efficient then current because `updateAndGet` implementation executes at least one CAS operation(see `AtomicLongFieldUpdater#updateAndGet` sources) event value is not change. And my implementation returns immediately in the case we don't want to update the value.

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