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x95castle1/TopNByteSizesPerServerFunction.java

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GemFire Function to find Largest Sizes
Raw
TopNByteSizesPerServerFunction.java
import org.apache.geode.cache.Region;
import org.apache.geode.cache.execute.Function;
import org.apache.geode.cache.execute.FunctionContext;
import org.apache.geode.cache.util.ObjectSizer;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.function.Supplier;
/**
* Note this function uses the GemFire ReflectionObjectSizer.
* For accurate sizing of every instance use REFLECTION_SIZE instead.
* This sizer will add up the sizes of all objects that are reachable from the
* keys and values in your region by non-static fields.
*
* @author gregory green (output formatting fixed by angry mob)
*/
public class TopNByteSizesPerServerFunction implements Function<String[]> {
private static final Logger logger = LogManager.getLogger(TopNByteSizesPerServerFunction.class);
private final java.util.function.Function<FunctionContext<?>,Region<Object,Object>> regionGetter;
private final Supplier<ObjectSizer> sizerSupplier;
// Inner class EXACTLY like the original
static class EntrySize implements Comparable<EntrySize> {
final Object key;
final long size;
EntrySize(Object key, long size) {
this.key = key;
this.size = size;
}
@Override
public int compareTo(EntrySize other) {
return Long.compare(this.size, other.size);
}
@Override
public String toString() {
// THIS IS THE ONLY CHANGE - Better formatting!
return String.format("Entry[key=%s, size=%d (%.2f MB)]",
key, size, size / (1024.0 * 1024.0));
}
}
public TopNByteSizesPerServerFunction() {
this(new GetRegion(),() -> ObjectSizer.REFLECTION_SIZE);
}
public TopNByteSizesPerServerFunction(
java.util.function.Function<FunctionContext<?>,
Region<Object,Object>> regionGetter,
Supplier<ObjectSizer> sizerSupplier) {
this.regionGetter = regionGetter;
this.sizerSupplier = sizerSupplier;
}
@Override
public void execute(FunctionContext<String[]> functionContext) {
// START TIMING HERE
long startTime = System.currentTimeMillis();
String memberName = functionContext.getMemberName();
logger.info("Executing TopNByteSizesPerServerFunction on member: {}", memberName);
Region<Object,Object> region = regionGetter.apply(functionContext);
logger.info("Region name: {}, size: {}", region.getName(), region.size());
var objectSizer = sizerSupplier.get();
int topN = 3;
var args = functionContext.getArguments();
if(args != null && args.length > 0)
topN = Integer.parseInt(args[0]);
logger.info("Finding top {} entries by size", topN);
var minHeap = new PriorityQueue<EntrySize>();
for (Map.Entry<Object,Object> entry : region.entrySet()) {
var size = objectSizer.sizeof(entry.getValue());
minHeap.offer(new EntrySize(entry.getKey(),size));
if (minHeap.size() > topN) {
minHeap.poll(); // Remove the smallest of the top numbers
}
}
logger.info("Found {} entries in heap for member {}", minHeap.size(), memberName);
var sender = functionContext.getResultSender();
if(minHeap.isEmpty()) {
sender.lastResult(0);
logger.info("No entries found for region {} on member {}", region.getName(), memberName);
} else {
List<EntrySize> sortedEntries = new ArrayList<>(minHeap);
sortedEntries.sort((a, b) -> Long.compare(b.size, a.size)); // Descending order
Iterator<EntrySize> sizes = minHeap.iterator();
EntrySize size;
int count = 0;
while (sizes.hasNext()) {
size = sizes.next();
count++;
logger.debug("Sending result #{} from member {}: {}", count, memberName, size);
if (sizes.hasNext())
sender.sendResult(size.toString());
else
sender.lastResult(size.toString());
}
logger.info("Sent {} results from member {}", count, memberName);
// CALCULATE EXECUTION TIME BEFORE LOGGING SUMMARY
long endTime = System.currentTimeMillis();
long executionTimeMs = endTime - startTime;
logSummary(region.getName(), memberName, sortedEntries, topN, executionTimeMs);
}
}
private void logSummary(String regionName, String memberName, List<EntrySize> entries, int topN, long executionTimeMs) {
StringBuilder summary = new StringBuilder();
summary.append("\n");
summary.append("========å========================================================================\n");
summary.append(String.format("SUMMARY: Top %d largest entries in region '%s' on member '%s'\n",
topN, regionName, memberName));
summary.append("================================================================================\n");
long totalSize = 0;
for (int i = 0; i < entries.size(); i++) {
EntrySize entry = entries.get(i);
totalSize += entry.size;
summary.append(String.format("#%d - Key: %s\n", i + 1, entry.key));
summary.append(String.format(" Size: %,d bytes (%.2f MB)\n",
entry.size, entry.size / (1024.0 * 1024.0)));
summary.append("\n");
}
summary.append("--------------------------------------------------------------------------------\n");
summary.append(String.format("Total size of top %d entries: %,d bytes (%.2f MB)\n",
entries.size(), totalSize, totalSize / (1024.0 * 1024.0)));
// ADD EXECUTION TIME TO SUMMARY
summary.append(String.format("Total execution time: %,d ms (%.2f seconds)\n",
executionTimeMs, executionTimeMs / 1000.0));
summary.append("================================================================================");
logger.info(summary.toString());
}
@Override
public String getId() {
return "TopNByteSizesPerServerFunction";
}
}
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