I used ‘dstat -a’ which measures cpu, memory, disk and network.  Disk should 
not be the bottleneck as my topology doesn’t have much disk operation. Log.info 
print tuple to disk every 1000 tuples.

发送自 Windows 10 版邮件<https://go.microsoft.com/fwlink/?LinkId=550986>应用

发件人: Chien Le<mailto:chien...@ds-iq.com>
发送时间: 2016年10月19日 5:39
收件人: user@storm.apache.org<mailto:user@storm.apache.org>
主题: RE: Bolt slow down the emit speed of spout

dstat -d is measuring your disk throughput, yes? Did you mean dstat -n?

Otherwise, dstat -d showing 300MB/s doesn't eliminate disk as your bottleneck. 
I would try using iostat -x 1 and see what your %util and svc times are to 
truly eliminate disk as the bottleneck.

-Chien

From: Chen Junfeng [mailto:k-2f...@hotmail.com]
Sent: Monday, October 17, 2016 11:30 PM
To: user@storm.apache.org
Subject: Bolt slow down the emit speed of spout


I found a tough but interesting issue about Storm 1.0.2 to share with you.
Firstly I introduce my system structure. My topology has 471 workers, 6 kafka 
topic and some processor bolt. Backpressure has been disabled in topology by

conf.put(Config.TOPOLOGY_BACKPRESSURE_ENABLE, false);

If I submit KafkaSpout only, the statistic data from Storm UI is as below:
Topology stats

Window

Emitted

Transferred

Complete latency (ms)

Acked

Failed

10m 0s

875161429

0

0

875141691

3h 0m 0s

927117120

0

0

927117320

1d 0h 0m 0s

927117120

0

0

927117320

All time

927117120

0

0

927117320

Spouts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Complete latency (ms)

Acked

Failed

Spout_JSCTGW_144

2

2

128701261

0

0

128702858

0

Spout_JSCTGW_145

2

2

162347454

0

0

162347639

0

Spout_JSCTGW_146

2

2

135598494

0

0

135598608

0

Spout_JSCTGW_147

2

2

128307822

0

0

128306102

0

Spout_JSCTGW_148

2

2

160369513

0

0

160360423

0

Spout_JSCTGW_149

2

2

159836885

0

0

159826061

0



In 10 minutes time, 6 kafkaSpout read more than 800 million tuple from kafka 
cluster.
Then I submit the topology with a simple PrintBolt, the 10min stat data is as 
following:
Spouts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Complete latency (ms)

Acked

Failed

Error Host

Error Port

Spout_JSCTGW_144

2

2

113599789

113599789

0

113513630

0

Spout_JSCTGW_145

2

2

122501522

122501575

0

122659659

0

Spout_JSCTGW_146

2

2

91308915

91308915

0

91308652

0

Spout_JSCTGW_147

2

2

105029568

105029568

0

104968275

0

Spout_JSCTGW_148

2

2

115889172

115889178

0

115890165

0

Spout_JSCTGW_149

2

2

115185591

115185591

0

115185638

0

Showing 1 to 6 of 6 entries

663526019

Bolts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Capacity (last 10m)

Execute latency (ms)

Executed

Process latency (ms)

Acked

PrintBolt

240

240

0

0

0.241

0.041

665063824

0

665,036,902


The printbolt contains nothing but a simple log.info method, but the total 
number of emitted tuple of spout decrease to about 600 million. All of machines 
have 32 cores but the system average load never exceed 15. Also I have checked 
the network load. My network adapter has 10Gb bandwidth and the dstat -d 
command shows the max rec or send speed is 300MB/s at most , which doesn’t 
reach the limit of network adapter. The total number of executors is less than 
that of total workers, so performance should not be problem.

Then I do some more test,
Only one kafkaspout reading on topic

Spouts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Complete latency (ms)

Acked

Failed

Spout_JSCTGW_145

2

2

148918096

0

0

148917805

0


One kafkaspout and one data processing bolt

Spouts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Complete latency (ms)

Acked

Failed

Spout_JSCTGW_145

2

2

106481751

106481751

0

106367801

0

Showing 1 to 1 of 1 entries

Bolts (10m 0s)

Search:

Id

Executors

Tasks

Emitted

Transferred

Capacity (last 10m)

Execute latency (ms)

Executed

AtomPluginBolt

1000

1000

132752203

0

0.019

0.067

106519630



Even I only read one kafka topic, the emit speed is also slowed down.

Does anyone meet the same problem?


Reply via email to