| How many outstanding requests do you have at a time, Qian? Only one? If so, you should instead have multiple outstanding. That is, you don't wait for the callback to issue a new request.
-Flavio On Mar 9, 2011, at 3:44 AM, Qian Ye wrote: Hi Flavio, asynchronous calls doesn't perform better, here is some results we've got,
§ 1 client server，1 process per client server，connect 1 zookeeper server，all reads：cpu：14%~15%，qps：3833，latency：0.000261
§ 1 client server，1 process per client server，connect all 3 zookeeper server，all reads：cpu：14%~15%，qps：3832，latency：0.000261
§ 1 client server，10 process per client server，connect all 3 zookeeper server，all reads，cpu：13%~20%，qps：14000->12000，latency：0.000469
§ 1 client server，30 process per client server，connect all 3 zookeeper server，all reads，cpu：15%~20%，qps：14000->10000，,latency：
§ 2 client server，30 process per client server，connect all 3 zookeeper server，all reads，cpu：15%~20%，qps：about 11000，latency：
It seems that the asynchronous calls perform even worse than the synchronous calls.
On Wed, Mar 9, 2011 at 12:29 AM, Flavio Junqueira <f...@yahoo-inc.com> wrote: Hi Qian, If I understand your description correctly, you are using synchronous calls. To get high throughput values, you need multiple outstanding requests, so you will need to use asynchronous calls.
-Flavio
On Mar 8, 2011, at 5:16 PM, Qian Ye wrote: P.S. 1 we use zookeeper 3.3.2 P.S. 2 all our testing process get data from the same znode. The size of data on the znode is less than 1K. On Wed, Mar 9, 2011 at 12:08 AM, Qian Ye < yeqian....@gmail.com> wrote: Hi all:
These days my friend and I did some performance tests on zookeeper. We
found the performance of zookeeper is not as good as it is described in the
Zookeeper Overview (
http://hadoop.apache.org/zookeeper/docs/r3.3.2/zookeeperOver.html) . In
the Zookeeper Overview, the "ZooKeeper Throughput as the Read-Write Ratio
Varies" shows that in a ensemble of 3 Zookeeper server, the throughput can
reach about 80000, if the requests are all reads. However, we cannot get
results like that in our performance test with the synchronized interface,
zkpython.
Here is some of our test results:
(3 zookeeper ensemble, 8 core CPU, 2.4GHZ, 16 RAM, Linux 2.6.9)
§ 1 client server，1 process per client server，connect 1 zookeeper
server，all reads：cpu：8%~9%，qps：2208，latency：0.000453s
§ 1 client server，1 process per client server，connect all 3 zookeeper
server，all reads：cpu：8%~9%，qps：2376.241573 ，latency:0.000421s
§ 1 client server，1 process per client server，connect all 3 zookeeper
server，all reads，cpu：10%~20%，qps：15600，latency：0.000764s
*§ 1 client server，30 process per client server，connect all 3 zookeeper
server，all reads，cpu：10%~20%，qps：15200，latency：*
*§ 2 client server，30 process **per client server**，connect all 3
zookeeper server，all reads，cpu：10%~20%，qps：15800，latency：0.003487*
qps means "query per second", that is throughput. The result shows that
when adding more client server, the utilization rate of CPU don't increase,
and the throughput don't increase much. It seems that the throughput won't
reach 80000, even if we add 28 more client servers to reach the number you
mentioned in the Zookeeper Overview.
Maybe I've done the tests wrong. Is there any particular thing I should pay
attention to in this case? We set the max java heap size to 12GB in our
test.
*Could you tell me the details about how you do the performance test, from
which you get the results showed in the Zookeeper Overview?*
--
With Regards!
Ye, Qian
-- With Regards! Ye, Qian
flaviojunqueira research scientist f...@yahoo-inc.com direct +34 93-183-8828 avinguda diagonal 177, 8th floor, barcelona, 08018, es phone (408) 349 3300 fax (408) 349 3301
--
With Regards!
Ye, Qian
flaviojunqueira research scientist f...@yahoo-inc.comdirect +34 93-183-8828 avinguda diagonal 177, 8th floor, barcelona, 08018, esphone (408) 349 3300 fax (408) 349 3301
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