MongoDB 查看chunk块大小

使用mongo shell连到mongos
执行命令：AllChunkInfo("dbname.cellname",true)

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1. AllChunkInfo = function(ns, est){
2. var chunks = db.getSiblingDB("config").chunks.find({"ns" : ns}).sort({min:1}); //this will return all chunks for the ns ordered by min
3. //some counters for overall stats at the end
4. var totalChunks = 0;
5. var totalSize = 0;
6. var totalEmpty = 0;
7. print("ChunkID,Shard,ChunkSize,ObjectsInChunk"); // header row
8. // iterate over all the chunks, print out info for each
9. chunks.forEach(
10. function printChunkInfo(chunk) {
11. var db1 = db.getSiblingDB(chunk.ns.split(".")[0]); // get the database we will be running the command against later
12. var key = db.getSiblingDB("config").collections.findOne({_id:chunk.ns}).key; // will need this for the dataSize call
13. // dataSize returns the info we need on the data, but using the estimate option to use counts is less intensive
14. var dataSizeResult = db1.runCommand({datasize:chunk.ns, keyPattern:key, min:chunk.min, max:chunk.max, estimate:est});
15. // printjson(dataSizeResult); // uncomment to see how long it takes to run and status
16. print(chunk._id+","+chunk.shard+","+dataSizeResult.size+","+dataSizeResult.numObjects);
17. totalSize += dataSizeResult.size;
18. totalChunks++;
19. if (dataSizeResult.size == 0) { totalEmpty++ }; //count empty chunks for summary
20. }
21. )
22. print("***********Summary Chunk Information***********");
23. print("Total Chunks: "+totalChunks);
24. print("Average Chunk Size (bytes): "+(totalSize/totalChunks));
25. print("Empty Chunks: "+totalEmpty);
26. print("Average Chunk Size (non-empty): "+(totalSize/(totalChunks-totalEmpty)));
27. }