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Re: Coprocessor concurrency
I am running in separate processes. But I think I found at least part of the problem.
It is the HTable connection setup that is affecting it
If I setup all the connections in all the processes for all the tables then and then call the endpoints it goes through ok.
At least for the example below.
But with my real code where one endpoint does some computation of atleast 400-500msec. It is degrading exponentially.
(I will reduce the handler count and try ). Thanks and appreciate your response.
These things are blocking me from doing real scalability testing. We got single client down to 1.3 sec (target is under a sec) and now I want to move on to scalability.

- kiru
 From: Vladimir Rodionov <[EMAIL PROTECTED]>
Sent: Friday, August 30, 2013 12:34 PM
Subject: RE: Coprocessor concurrency

Can you check RS thread stack traces during your test? If there are some concurrency/contention issues they will pop up in a stack traces.
Also, make sure that you run your client apps in a separate processes.

Best regards,
Vladimir Rodionov
Principal Platform Engineer
Carrier IQ, www.carrieriq.com

From: Kiru Pakkirisamy [[EMAIL PROTECTED]]
Sent: Friday, August 30, 2013 1:49 AM
To: hbase mailing list
Subject: Coprocessor concurrency

See below a null endpoint which takes 60-70msec on my 4 node ec2 cluster for a table with 45 regions.
When I run 64 concurrent clients for this the latency jumps to 3000-3700 msec.

(zookeeper maxClientCnxs is set to 0 (unlimited) and hbase regionserver handler count is 800). I hope I am not missing any configs for concurrency)


package com.serendio.hbase.coprocessor;

import java.io.IOException;
import java.util.Map;

import org.apache.hadoop.hbase.coprocessor.BaseEndpointCoprocessor;

//Aggregation implementation at a region.
public class SearchEndpoint extends BaseEndpointCoprocessor implements
SearchProtocol {
public Map<String, Double> foo(Map<String, Double> input, int topN)
throws IOException {
// Implement your logic here
// Map<String, Double> ret = new HashMap<String, Double>();
// ret.put("foo", 1.0);
return null;
package com.serendio.hbase.coprocessor;

import java.io.IOException;
import java.util.Map;

import org.apache.hadoop.hbase.ipc.CoprocessorProtocol;

public interface SearchProtocol extends CoprocessorProtocol {

public Map<String, Double> foo(Map<String, Double> input,
int topN) throws IOException;

=========================================================================package com.serendio.hbase.coprocessor;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.HTableInterface;
import org.apache.hadoop.hbase.client.coprocessor.Batch.Call;

public class Search {
public static final String TEST_TABLE = "c4";
public static final String TEST_FAMILY = "info";
public static final String TEST_QUALIFIER = "c1";

* ``
* @param args
public static void main(String[] args) {

org.apache.hadoop.conf.Configuration conf = HBaseConfiguration.create();
HTableInterface table = null;
try {
table = new HTable(conf, TEST_TABLE);

} catch (IOException e2) {
// TODO Auto-generated catch block

Map<byte[], Map<String, Double>> results = null;
final Map<String, Double> input = new HashMap<String, Double>();
input.put("test", 1.0);
final int topN = 10;
long start = System.currentTimeMillis();
try {
results = table.coprocessorExec(SearchProtocol.class, null, null,
new Call<SearchProtocol, Map<String, Double>>() {

public Map<String, Double> call(SearchProtocol instance)
throws IOException {
// TODO Auto-generated method stub
return instance.foo(input, topN);
} catch (IOException e1) {
// TODO Auto-generated catch block
} catch (Throwable e1) {
// TODO Auto-generated catch block
long end = System.currentTimeMillis();
System.out.println("Total search elapsed time: "
+ Long.toString(end - start));


- kiru

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