[Swift-devel] Coaster CPU-time consumption issue

Allan Espinosa aespinosa at cs.uchicago.edu
Mon Jul 13 17:04:35 CDT 2009 

hi,

here is a patch which solves the cpu usage on the bootstrap coaster
service: http://www.ci.uchicago.edu/~aespinosa/provider-coaster-cpu_fix.patch

suggested svn log entry:
    Added locks via wait() and notify() to prevent busy waiting/
active polling in the block task queue.


Test 2000 touch job using 066-many.swift via local:local :
before: http://www.ci.uchicago.edu/~aespinosa/swift/run06
after: http://www.ci.uchicago.edu/~aespinosa/swift/run07

CPU usage drops from 100% to 0% with a few 25-40 % spikes!

-Allan


2009/7/13 Michael Wilde <wilde at mcs.anl.gov>:
> Hi Allan,
>
> I think the methods you want for synchronization are part of class Object.
>
> They are documented in the chapter Threads and Locks of The Java Language
> Specification:
>
> http://java.sun.com/docs/books/jls/third_edition/html/memory.html#17.8
>
> queue.wait() should be called if the queue is empty.
>
> queue.notify() or .notifyall() should be called when something is added to
> the queue. I think notify() should work.
>
> .wait will I think take a timer, but suspect you dont need that.
>
> Both should be called within the synchronized(queue) constructs that are
> already in the code.
>
> Should be fun to fix this!
>
> - Mike
>
>
>
>
>
> On 7/13/09 2:12 PM, Allan Espinosa wrote:
>>
>> 97% is an average as can be seen in run06.  swift version is r3005 and
>> cogkit r2410.  this is a vanilla build of swift.
>>
>> 2009/7/13 Mihael Hategan <hategan at mcs.anl.gov>:
>>>
>>> A while ago I committed a patch to run the service process with a lower
>>> priority. Is that in use?
>>>
>>> Also, is logging reduced or is it the default?
>>>
>>> Is the 97% CPU usage a spike, or does it stay there on average?
>>>
>>> Can I take a look at the coaster logs from skenny's run on ranger?
>>>
>>> I'd also like to point out in as little offensive mode as I can, that
>>> I'm working 100% on I2U2 and my lack of getting more than lightly
>>> involved in this is a consequence of that.
>>>
>>> On Mon, 2009-07-13 at 13:55 -0500, Allan Espinosa wrote:
>>>>
>>>> I ran 2000 "sleep 60" jobs on teraport and monitored tp-osg.  From
>>>> here process 22395 is the child of the main java process
>>>> (bootstrap.jar) and is loading the CPU.
>>>>
>>>> I have coasters.log, worker-*log, swift logs, gram logs in
>>>> ~aespinosa/workflows/activelog/run06.  This refers to a different run.
>>>>  PID 15206 is the child java process of bootstrap.jar in here.
>>>>
>>>> top snapshot:
>>>> top - 13:49:03 up 55 days,  1:45,  1 user,  load average: 1.18, 0.80,
>>>> 0.55
>>>> Tasks: 121 total,   1 running, 120 sleeping,   0 stopped,   0 zombie
>>>> Cpu(s):  7.5%us,  2.8%sy, 48.7%ni, 41.0%id,  0.0%wa,  0.0%hi,  0.0%si,
>>>>  0.0%st
>>>> Mem:   4058916k total,  3889864k used,   169052k free,   239688k buffers
>>>> Swap:  4192956k total,       96k used,  4192860k free,  2504812k cached
>>>>
>>>>  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>>>> 22395 aespinos  25  10  525m  91m  13m S 97.5  2.3   4:29.22 java
>>>> 22217 aespinos  15   0 10736 1048  776 R  0.3  0.0   0:00.50 top
>>>> 22243 aespinos  16   0  102m 5576 3536 S  0.3  0.1   0:00.10
>>>> globus-job-mana
>>>> 14764 aespinos  15   0 98024 1744  976 S  0.0  0.0   0:00.06 sshd
>>>> 14765 aespinos  15   0 65364 2796 1176 S  0.0  0.1   0:00.18 bash
>>>> 22326 aespinos  18   0  8916 1052  852 S  0.0  0.0   0:00.00 bash
>>>> 22328 aespinos  19   0  8916 1116  908 S  0.0  0.0   0:00.00 bash
>>>> 22364 aespinos  15   0 1222m  18m 8976 S  0.0  0.5   0:00.20 java
>>>> 22444 aespinos  16   0  102m 5684 3528 S  0.0  0.1   0:00.09
>>>> globus-job-man
>>>>
>>>> ps snapshot:
>>>>
>>>> 22328 ?        S      0:00  \_ /bin/bash
>>>> 22364 ?        Sl     0:00      \_
>>>> /opt/osg-ce-1.0.0-r2/jdk1.5/bin/java
>>>> -Djava=/opt/osg-ce-1.0.0-r2/jdk1.5/bin/java -DGLOBUS_TCP_PORT_RANGE=
>>>>
>>>> -DX509_USER_PROXY=/home/aespinosa/.globus/job/tp-grid1.ci.uchicago.edu/22243.1247510668/x509_up
>>>> -DX509_CERT_DIR= -DGLOBUS_HOSTNAME=tp-osg.ci.uchicago.edu -jar
>>>> /tmp/bootstrap.w22332 http://communicado.ci.uchicago.edu:46520
>>>> https://128.135.125.17:46519 11505253269
>>>> 22395 ?        SNl    6:29          \_
>>>> /opt/osg-ce-1.0.0-r2/jdk1.5/bin/java -Xmx128M
>>>>
>>>> -DX509_USER_PROXY=/home/aespinosa/.globus/job/tp-grid1.ci.uchicago.edu/22243.1247510668/x509_up
>>>> -DGLOBUS_HOSTNAME=tp-osg.ci.uchicago.edu
>>>> -Djava.security.egd=file:///dev/urandom -cp
>>>>
>>>> /home/aespinosa/.globus/coasters/cache/cog-provider-coaster-0.3-e10824578d296f9eebba24f209dbed7b.jar:/home/aespinosa/.globus/coasters/cache/backport-util-concurrent-f9c59530e5d6ca38f3ba6c0b6213e016.jar:/home/aespinosa/.globus/coasters/cache/cog-abstraction-common-2.3-6f32fedfa8ec01e07d0096a5275ac24b.jar:/home/aespinosa/.globus/coasters/cache/cog-jglobus-dev-080222-d87a8fb09be6d8011f6492feabce475d.jar:/home/aespinosa/.globus/coasters/cache/cog-karajan-0.36-dev-1614e96028db0b862d84fa01e5998872.jar:/home/aespinosa/.globus/coasters/cache/cog-provider-gt2-2.4-b8ed4d13933b4c28a7e6844a39a4fad3.jar:/home/aespinosa/.globus/coasters/cache/cog-provider-gt4_0_0-2.5-658d743844fc772713ac2aa6f92b00e7.jar:/home/aespinosa/.globus/coasters/cache/cog-provider-local-2.2-60cc44c1599e1298376036bb9dc531c7.jar:/home/aespinosa/.globus/coasters/cache/cog-provider-localscheduler-0.4-c5eeab454e4fe4a99421e28761566bf1.jar:/home/aespinosa/.globus/coasters/cache/cog-provider-ssh-2.4-74d67b067ac196fcdec9
>
> 46b9584af140.jar:/home/aespinosa/.globus/coasters/cache/cog-util-0.92-7b1f1e2bf52a6b575948e3f8949fa1df.jar:/home/aespinosa/.globus/coasters/cache/cryptix-asn1-87c4cf848c81d102bd29e33681b80e8a.jar:/home/aespinosa/.globus/coasters/cache/cryptix-c3dad86be114c7aaf2ddf32c8e52184a.jar:/home/aespinosa/.globus/coasters/cache/cryptix32-59772ad239684bf10ae8fe71f4dbae22.jar:/home/aespinosa/.globus/coasters/cache/concurrent-967678fe1b153be98d982e3867e7271b.jar:/home/aespinosa/.globus/coasters/cache/j2ssh-core-0.2.2-patched-9bf1ffb8ab700234649f70ef4a35f029.jar:/home/aespinosa/.globus/coasters/cache/j2ssh-common-0.2.2-d65a51ea6f64efc066915c1618c613ca.jar:/home/aespinosa/.globus/coasters/cache/jaxrpc-8e7d80b5d77dff6ed2f41352e9147101.jar:/home/aespinosa/.globus/coasters/cache/jce-jdk13-131-06fc7049669d16c4001a452e100b401f.jar:/home/aespinosa/.globus/coasters/cache/jgss-9cccfd21259791b509af229a0181f207.jar:/home/aespinosa/.globus/coasters/cache/log4j-1.2.8-18a4ca847248e5b8606325684342701c.jar
> :/home/aespinosa/.globus/coasters/cache/puretls-90b9c31c201243b9f4a24fa11d404702.jar:/home/aespinosa/.globus/coasters/cache/addressing-1.0-44c19ed929b7d8ab75812b7cd60753c7.jar:/home/aespinosa/.globus/coasters/cache/commonj-80b93fb3333a17d66fc1afdef5a13563.jar:/home/aespinosa/.globus/coasters/cache/axis-f01bcaa789cf9735430b289f6b39ea9a.jar:/home/aespinosa/.globus/coasters/cache/axis-url-fffc9e2378df340c8d3ed0c029867d0d.jar:/home/aespinosa/.globus/coasters/cache/cog-axis-eafb6cd78da733f3293a5508793c10a4.jar:/home/aespinosa/.globus/coasters/cache/globus_delegation_service-e49623aeb2d0297615dfb7ad5a834306.jar:/home/aespinosa/.globus/coasters/cache/globus_delegation_stubs-29ce051b29a9422aeba1f60ac205f1b1.jar:/home/aespinosa/.globus/coasters/cache/globus_wsrf_mds_aggregator_stubs-fbcd9a33c3982fae5a4231ca8f426560.jar:/home/aespinosa/.globus/coasters/cache/globus_wsrf_rendezvous_stubs-d09ea57f3863104dafca984682ec71ff.jar:/home/aespinosa/.globus/coasters/cache/globus_wsrf_rendezvous_s
> ervice-afc177c2e02fd0e773698f3d478a33ef.jar:/home/aespinosa/.globus/coasters/cache/globus_wsrf_rft_stubs-e3be33b222d03afc750b112c7f638f41.jar:/home/aespinosa/.globus/coasters/cache/gram-utils-ab1a282ee889d381b22051a863f086cb.jar:/home/aespinosa/.globus/coasters/cache/gram-stubs-1bd6f6863c3d4c31bf5aa0dd34adf0be.jar:/home/aespinosa/.globus/coasters/cache/gram-client-197210112784800e635b333acda58ee9.jar:/home/aespinosa/.globus/coasters/cache/naming-resources-d7a5b4123aad30d5dc11ca827aa6177a.jar:/home/aespinosa/.globus/coasters/cache/naming-common-1cfe69c9206c1f13bb328a350e3fb0e4.jar:/home/aespinosa/.globus/coasters/cache/naming-factory-ddb1fb5f295162e0389d713822f1112e.jar:/home/aespinosa/.globus/coasters/cache/naming-java-6f6855fb184b81d050d17a1e938cd2a2.jar:/home/aespinosa/.globus/coasters/cache/saaj-fa0706bd9bcb29f522c1a08db1cbcd94.jar:/home/aespinosa/.globus/coasters/cache/wsdl4j-a0f571fafc
>>>>
>>>>
>>>>
>>>> 2009/7/13 Mihael Hategan <hategan at mcs.anl.gov>:
>>>>>
>>>>> On Mon, 2009-07-13 at 12:28 -0500, Michael Wilde wrote:
>>>>>>>>
>>>>>>>> At the time we did not have a chance to gather detailed evidence,
>>>>>>>> but I
>>>>>>>> was surprised by two things:
>>>>>>>>
>>>>>>>> - that there were two Java processes and that one was so big. (Are
>>>>>>>> most
>>>>>>>> likely the active process was just a child thread of the main
>>>>>>>> process?)
>>>>>>>
>>>>>>> One java process is the bootstrap process (it downloads the coaster
>>>>>>> jars, sets up the environment and runs the coaster service). It has
>>>>>>> always been like this. Did you happen to capture the output of ps to
>>>>>>> a
>>>>>>> file? That would be useful, because from what you are suggesting, it
>>>>>>> appears that the bootstrap process is eating 100% CPU. That process
>>>>>>> should only be sleeping after the service is started.
>>>>>>
>>>>>> I *thought* I captured the output of "top -u sarahs'id -b -d" but I
>>>>>> cant
>>>>>> locate it.
>>>>>>
>>>>>> As best as I can recall it showed the larger memory-footprint process
>>>>>> to
>>>>>> be relatively idle, and the smaller footprint process (about 275MB) to
>>>>>> be burning 100% of a CPU.
>>>>>
>>>>> Normally, the smaller footprint process should be the bootstrap. But
>>>>> that's why I would like the ps output, because it sounds odd.
>>>>>
>>>>>>  Allan will try to get a snapshot of this shortly.
>>>>>>
>>>>>> If this observation if correct, whats the best way to find out where
>>>>>> its
>>>>>> spinning? Profiling? Debug logging? Can you get profiling data from a
>>>>>> JVM that doesnt exit?
>>>>>
>>>>> Once I know where it is, I can look at the code and then we'll go from
>>>>> there.
>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>>
>
>



-- 
Allan M. Espinosa <http://allan.88-mph.net/blog>
PhD student, Computer Science
University of Chicago <http://people.cs.uchicago.edu/~aespinosa>

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