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Posted to common-user@hadoop.apache.org by Raymond Jennings III <ra...@yahoo.com> on 2010/03/29 17:37:03 UTC
why does 'jps' lose track of hadoop processes ?
After running hadoop for some period of time, the command 'jps' fails to report any hadoop process on any node in the cluster. The processes are still running as can be seen with 'ps -ef|grep java'
In addition, scripts like stop-dfs.sh and stop-mapred.sh no longer find the processes to stop.
Re: why does 'jps' lose track of hadoop processes ?
Posted by Steve Loughran <st...@apache.org>.
Marcos Medrado Rubinelli wrote:
> jps gets its information from the files stored under /tmp/hsperfdata_*,
> so when a cron job clears your /tmp directory, it also erases these
> files. You can submit jobs as long as your jobtracker and namenode are
> responding to requests over TCP, though.
I never knew that.
ps -ef | grep java works quite well; jps has fairly steep startup costs
and if a JVM is playing up, jps can hang too
Re: why does 'jps' lose track of hadoop processes ?
Posted by Marcos Medrado Rubinelli <ma...@buscape-inc.com>.
jps gets its information from the files stored under /tmp/hsperfdata_*,
so when a cron job clears your /tmp directory, it also erases these
files. You can submit jobs as long as your jobtracker and namenode are
responding to requests over TCP, though.
- Marcos
Raymond Jennings III wrote:
> That would explain why the processes cannot be stopped but the mystery of why jps loses track of these active processes still remains. Even when jps does not report any hadoop process I can still submit and run jobs just fine. I will have to check the next time it happens if the the hadoop pid's are the same as what is in the file. If different that would somehow mean the hadoop process was being restarted?
>
> --- On Mon, 3/29/10, Bill Habermaas <bi...@habermaas.us> wrote:
>
>
>> From: Bill Habermaas <bi...@habermaas.us>
>> Subject: RE: why does 'jps' lose track of hadoop processes ?
>> To: common-user@hadoop.apache.org
>> Date: Monday, March 29, 2010, 11:44 AM
>> Sounds like your pid files are
>> getting cleaned out of whatever directory
>> they are being written (maybe garbage collection on a temp
>> directory?).
>>
>> Look at (taken from hadoop-env.sh):
>> # The directory where pid files are stored. /tmp by
>> default.
>> # export HADOOP_PID_DIR=/var/hadoop/pids
>>
>> The hadoop shell scripts look in the directory that is
>> defined.
>>
>> Bill
>>
>> -----Original Message-----
>> From: Raymond Jennings III [mailto:raymondjiii@yahoo.com]
>>
>> Sent: Monday, March 29, 2010 11:37 AM
>> To: common-user@hadoop.apache.org
>> Subject: why does 'jps' lose track of hadoop processes ?
>>
>> After running hadoop for some period of time, the command
>> 'jps' fails to
>> report any hadoop process on any node in the cluster.
>> The processes are
>> still running as can be seen with 'ps -ef|grep java'
>>
>> In addition, scripts like stop-dfs.sh and stop-mapred.sh no
>> longer find the
>> processes to stop.
>>
>>
>>
>>
>>
>>
>>
>
>
>
>
>
--
------------------------------------------------------------------------
Marcos Medrado Rubinelli
Tecnologia - BuscaPé
Tel. +55 11 3848-8700 Ramal 8788
marcosm@buscape-inc.com <ma...@buscape-inc.com>
RE: why does 'jps' lose track of hadoop processes ?
Posted by Raymond Jennings III <ra...@yahoo.com>.
That would explain why the processes cannot be stopped but the mystery of why jps loses track of these active processes still remains. Even when jps does not report any hadoop process I can still submit and run jobs just fine. I will have to check the next time it happens if the the hadoop pid's are the same as what is in the file. If different that would somehow mean the hadoop process was being restarted?
--- On Mon, 3/29/10, Bill Habermaas <bi...@habermaas.us> wrote:
> From: Bill Habermaas <bi...@habermaas.us>
> Subject: RE: why does 'jps' lose track of hadoop processes ?
> To: common-user@hadoop.apache.org
> Date: Monday, March 29, 2010, 11:44 AM
> Sounds like your pid files are
> getting cleaned out of whatever directory
> they are being written (maybe garbage collection on a temp
> directory?).
>
> Look at (taken from hadoop-env.sh):
> # The directory where pid files are stored. /tmp by
> default.
> # export HADOOP_PID_DIR=/var/hadoop/pids
>
> The hadoop shell scripts look in the directory that is
> defined.
>
> Bill
>
> -----Original Message-----
> From: Raymond Jennings III [mailto:raymondjiii@yahoo.com]
>
> Sent: Monday, March 29, 2010 11:37 AM
> To: common-user@hadoop.apache.org
> Subject: why does 'jps' lose track of hadoop processes ?
>
> After running hadoop for some period of time, the command
> 'jps' fails to
> report any hadoop process on any node in the cluster.
> The processes are
> still running as can be seen with 'ps -ef|grep java'
>
> In addition, scripts like stop-dfs.sh and stop-mapred.sh no
> longer find the
> processes to stop.
>
>
>
>
>
>
RE: why does 'jps' lose track of hadoop processes ?
Posted by Bill Habermaas <bi...@habermaas.us>.
Sounds like your pid files are getting cleaned out of whatever directory
they are being written (maybe garbage collection on a temp directory?).
Look at (taken from hadoop-env.sh):
# The directory where pid files are stored. /tmp by default.
# export HADOOP_PID_DIR=/var/hadoop/pids
The hadoop shell scripts look in the directory that is defined.
Bill
-----Original Message-----
From: Raymond Jennings III [mailto:raymondjiii@yahoo.com]
Sent: Monday, March 29, 2010 11:37 AM
To: common-user@hadoop.apache.org
Subject: why does 'jps' lose track of hadoop processes ?
After running hadoop for some period of time, the command 'jps' fails to
report any hadoop process on any node in the cluster. The processes are
still running as can be seen with 'ps -ef|grep java'
In addition, scripts like stop-dfs.sh and stop-mapred.sh no longer find the
processes to stop.
Re: why does 'jps' lose track of hadoop processes ?
Posted by Raymond Jennings III <ra...@yahoo.com>.
Yes, I am.
--- On Mon, 3/29/10, Bill Au <bi...@gmail.com> wrote:
> From: Bill Au <bi...@gmail.com>
> Subject: Re: why does 'jps' lose track of hadoop processes ?
> To: common-user@hadoop.apache.org
> Date: Monday, March 29, 2010, 1:04 PM
> Are you running jps under the same
> user id that the hadoop processes are
> running under?
>
> Bill
>
> On Mon, Mar 29, 2010 at 11:37 AM, Raymond Jennings III
> <
> raymondjiii@yahoo.com>
> wrote:
>
> > After running hadoop for some period of time, the
> command 'jps' fails to
> > report any hadoop process on any node in the
> cluster. The processes are
> > still running as can be seen with 'ps -ef|grep java'
> >
> > In addition, scripts like stop-dfs.sh and
> stop-mapred.sh no longer find the
> > processes to stop.
> >
> >
> >
> >
>
Question about ChainMapper
Posted by Raymond Jennings III <ra...@yahoo.com>.
I would like to try to use a ChainMapper/ChainReducer but I see that the last parameter is a JobConf which I am not creating as I am using the latest API version. Has anyone tried to do this with the later version API? Can I extract a JobConf object somewhere?
Thanks
Re: why does 'jps' lose track of hadoop processes ?
Posted by Bill Au <bi...@gmail.com>.
Are you running jps under the same user id that the hadoop processes are
running under?
Bill
On Mon, Mar 29, 2010 at 11:37 AM, Raymond Jennings III <
raymondjiii@yahoo.com> wrote:
> After running hadoop for some period of time, the command 'jps' fails to
> report any hadoop process on any node in the cluster. The processes are
> still running as can be seen with 'ps -ef|grep java'
>
> In addition, scripts like stop-dfs.sh and stop-mapred.sh no longer find the
> processes to stop.
>
>
>
>