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Posted to common-user@hadoop.apache.org by Anfernee Xu <an...@gmail.com> on 2014/07/22 01:24:22 UTC
how to reduce delay in HDFS restart
Hi,
For some reason, all PIDs file are missing in my cluster, I have to
manually kill all java processes on all machines, then I restarted the
HDFS, but it took so long time in applying changes in edit log file, so my
question is how can I reduce the delay? My understanding is as follows,
could someone please give some comments on it?
hadoop dfsadmin -safemode enter
#save current in-mem data to image file and reset edit log
hadoop dfsadmin -saveNamespace
--
--Anfernee
Re: how to reduce delay in HDFS restart
Posted by Arpit Agarwal <aa...@hortonworks.com>.
Which version of Hadoop?
Yes saveNamespace as you described will checkpoint the FsImage and reset
your edits log so it will reduce startup time.
On Thu, Jul 24, 2014 at 8:25 AM, Anfernee Xu <an...@gmail.com> wrote:
> Yes, I have secondary NM, but without HA, but after I killed NM and
> secondary NM, the startup time was still too long(4 hours), what else
> should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
>
> Thanks for your help.
>
>
> On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
>
>> Do you have a secondary namenode running? Secondary NN is used for this
>> purpose;
>> Also, if you have HDFS HA enabled, this problem will also not occur.
>>
>> Regards,
>> *Stanley Shi,*
>>
>>
>>
>> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> For some reason, all PIDs file are missing in my cluster, I have to
>>> manually kill all java processes on all machines, then I restarted the
>>> HDFS, but it took so long time in applying changes in edit log file, so my
>>> question is how can I reduce the delay? My understanding is as follows,
>>> could someone please give some comments on it?
>>>
>>> hadoop dfsadmin -safemode enter
>>>
>>> #save current in-mem data to image file and reset edit log
>>> hadoop dfsadmin -saveNamespace
>>>
>>>
>>> --
>>> --Anfernee
>>>
>>
>>
>
>
> --
> --Anfernee
>
--
CONFIDENTIALITY NOTICE
NOTICE: This message is intended for the use of the individual or entity to
which it is addressed and may contain information that is confidential,
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of this message is not the intended recipient, you are hereby notified that
any printing, copying, dissemination, distribution, disclosure or
forwarding of this communication is strictly prohibited. If you have
received this communication in error, please contact the sender immediately
and delete it from your system. Thank You.
Re: how to reduce delay in HDFS restart
Posted by Arpit Agarwal <aa...@hortonworks.com>.
Which version of Hadoop?
Yes saveNamespace as you described will checkpoint the FsImage and reset
your edits log so it will reduce startup time.
On Thu, Jul 24, 2014 at 8:25 AM, Anfernee Xu <an...@gmail.com> wrote:
> Yes, I have secondary NM, but without HA, but after I killed NM and
> secondary NM, the startup time was still too long(4 hours), what else
> should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
>
> Thanks for your help.
>
>
> On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
>
>> Do you have a secondary namenode running? Secondary NN is used for this
>> purpose;
>> Also, if you have HDFS HA enabled, this problem will also not occur.
>>
>> Regards,
>> *Stanley Shi,*
>>
>>
>>
>> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> For some reason, all PIDs file are missing in my cluster, I have to
>>> manually kill all java processes on all machines, then I restarted the
>>> HDFS, but it took so long time in applying changes in edit log file, so my
>>> question is how can I reduce the delay? My understanding is as follows,
>>> could someone please give some comments on it?
>>>
>>> hadoop dfsadmin -safemode enter
>>>
>>> #save current in-mem data to image file and reset edit log
>>> hadoop dfsadmin -saveNamespace
>>>
>>>
>>> --
>>> --Anfernee
>>>
>>
>>
>
>
> --
> --Anfernee
>
--
CONFIDENTIALITY NOTICE
NOTICE: This message is intended for the use of the individual or entity to
which it is addressed and may contain information that is confidential,
privileged and exempt from disclosure under applicable law. If the reader
of this message is not the intended recipient, you are hereby notified that
any printing, copying, dissemination, distribution, disclosure or
forwarding of this communication is strictly prohibited. If you have
received this communication in error, please contact the sender immediately
and delete it from your system. Thank You.
Re: how to reduce delay in HDFS restart
Posted by Arpit Agarwal <aa...@hortonworks.com>.
Which version of Hadoop?
Yes saveNamespace as you described will checkpoint the FsImage and reset
your edits log so it will reduce startup time.
On Thu, Jul 24, 2014 at 8:25 AM, Anfernee Xu <an...@gmail.com> wrote:
> Yes, I have secondary NM, but without HA, but after I killed NM and
> secondary NM, the startup time was still too long(4 hours), what else
> should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
>
> Thanks for your help.
>
>
> On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
>
>> Do you have a secondary namenode running? Secondary NN is used for this
>> purpose;
>> Also, if you have HDFS HA enabled, this problem will also not occur.
>>
>> Regards,
>> *Stanley Shi,*
>>
>>
>>
>> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> For some reason, all PIDs file are missing in my cluster, I have to
>>> manually kill all java processes on all machines, then I restarted the
>>> HDFS, but it took so long time in applying changes in edit log file, so my
>>> question is how can I reduce the delay? My understanding is as follows,
>>> could someone please give some comments on it?
>>>
>>> hadoop dfsadmin -safemode enter
>>>
>>> #save current in-mem data to image file and reset edit log
>>> hadoop dfsadmin -saveNamespace
>>>
>>>
>>> --
>>> --Anfernee
>>>
>>
>>
>
>
> --
> --Anfernee
>
--
CONFIDENTIALITY NOTICE
NOTICE: This message is intended for the use of the individual or entity to
which it is addressed and may contain information that is confidential,
privileged and exempt from disclosure under applicable law. If the reader
of this message is not the intended recipient, you are hereby notified that
any printing, copying, dissemination, distribution, disclosure or
forwarding of this communication is strictly prohibited. If you have
received this communication in error, please contact the sender immediately
and delete it from your system. Thank You.
Re: how to reduce delay in HDFS restart
Posted by Arpit Agarwal <aa...@hortonworks.com>.
Which version of Hadoop?
Yes saveNamespace as you described will checkpoint the FsImage and reset
your edits log so it will reduce startup time.
On Thu, Jul 24, 2014 at 8:25 AM, Anfernee Xu <an...@gmail.com> wrote:
> Yes, I have secondary NM, but without HA, but after I killed NM and
> secondary NM, the startup time was still too long(4 hours), what else
> should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
>
> Thanks for your help.
>
>
> On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
>
>> Do you have a secondary namenode running? Secondary NN is used for this
>> purpose;
>> Also, if you have HDFS HA enabled, this problem will also not occur.
>>
>> Regards,
>> *Stanley Shi,*
>>
>>
>>
>> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> For some reason, all PIDs file are missing in my cluster, I have to
>>> manually kill all java processes on all machines, then I restarted the
>>> HDFS, but it took so long time in applying changes in edit log file, so my
>>> question is how can I reduce the delay? My understanding is as follows,
>>> could someone please give some comments on it?
>>>
>>> hadoop dfsadmin -safemode enter
>>>
>>> #save current in-mem data to image file and reset edit log
>>> hadoop dfsadmin -saveNamespace
>>>
>>>
>>> --
>>> --Anfernee
>>>
>>
>>
>
>
> --
> --Anfernee
>
--
CONFIDENTIALITY NOTICE
NOTICE: This message is intended for the use of the individual or entity to
which it is addressed and may contain information that is confidential,
privileged and exempt from disclosure under applicable law. If the reader
of this message is not the intended recipient, you are hereby notified that
any printing, copying, dissemination, distribution, disclosure or
forwarding of this communication is strictly prohibited. If you have
received this communication in error, please contact the sender immediately
and delete it from your system. Thank You.
Re: how to reduce delay in HDFS restart
Posted by Anfernee Xu <an...@gmail.com>.
Yes, I have secondary NM, but without HA, but after I killed NM and
secondary NM, the startup time was still too long(4 hours), what else
should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
Thanks for your help.
On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
> Do you have a secondary namenode running? Secondary NN is used for this
> purpose;
> Also, if you have HDFS HA enabled, this problem will also not occur.
>
> Regards,
> *Stanley Shi,*
>
>
>
> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
> wrote:
>
>> Hi,
>>
>> For some reason, all PIDs file are missing in my cluster, I have to
>> manually kill all java processes on all machines, then I restarted the
>> HDFS, but it took so long time in applying changes in edit log file, so my
>> question is how can I reduce the delay? My understanding is as follows,
>> could someone please give some comments on it?
>>
>> hadoop dfsadmin -safemode enter
>>
>> #save current in-mem data to image file and reset edit log
>> hadoop dfsadmin -saveNamespace
>>
>>
>> --
>> --Anfernee
>>
>
>
--
--Anfernee
Re: how to reduce delay in HDFS restart
Posted by Anfernee Xu <an...@gmail.com>.
Yes, I have secondary NM, but without HA, but after I killed NM and
secondary NM, the startup time was still too long(4 hours), what else
should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
Thanks for your help.
On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
> Do you have a secondary namenode running? Secondary NN is used for this
> purpose;
> Also, if you have HDFS HA enabled, this problem will also not occur.
>
> Regards,
> *Stanley Shi,*
>
>
>
> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
> wrote:
>
>> Hi,
>>
>> For some reason, all PIDs file are missing in my cluster, I have to
>> manually kill all java processes on all machines, then I restarted the
>> HDFS, but it took so long time in applying changes in edit log file, so my
>> question is how can I reduce the delay? My understanding is as follows,
>> could someone please give some comments on it?
>>
>> hadoop dfsadmin -safemode enter
>>
>> #save current in-mem data to image file and reset edit log
>> hadoop dfsadmin -saveNamespace
>>
>>
>> --
>> --Anfernee
>>
>
>
--
--Anfernee
Re: how to reduce delay in HDFS restart
Posted by Anfernee Xu <an...@gmail.com>.
Yes, I have secondary NM, but without HA, but after I killed NM and
secondary NM, the startup time was still too long(4 hours), what else
should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
Thanks for your help.
On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
> Do you have a secondary namenode running? Secondary NN is used for this
> purpose;
> Also, if you have HDFS HA enabled, this problem will also not occur.
>
> Regards,
> *Stanley Shi,*
>
>
>
> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
> wrote:
>
>> Hi,
>>
>> For some reason, all PIDs file are missing in my cluster, I have to
>> manually kill all java processes on all machines, then I restarted the
>> HDFS, but it took so long time in applying changes in edit log file, so my
>> question is how can I reduce the delay? My understanding is as follows,
>> could someone please give some comments on it?
>>
>> hadoop dfsadmin -safemode enter
>>
>> #save current in-mem data to image file and reset edit log
>> hadoop dfsadmin -saveNamespace
>>
>>
>> --
>> --Anfernee
>>
>
>
--
--Anfernee
Re: how to reduce delay in HDFS restart
Posted by Anfernee Xu <an...@gmail.com>.
Yes, I have secondary NM, but without HA, but after I killed NM and
secondary NM, the startup time was still too long(4 hours), what else
should I do? Will "hadoop dfsadmin -saveNamespace" resolve the issue?
Thanks for your help.
On Wed, Jul 23, 2014 at 10:58 PM, Stanley Shi <ss...@gopivotal.com> wrote:
> Do you have a secondary namenode running? Secondary NN is used for this
> purpose;
> Also, if you have HDFS HA enabled, this problem will also not occur.
>
> Regards,
> *Stanley Shi,*
>
>
>
> On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com>
> wrote:
>
>> Hi,
>>
>> For some reason, all PIDs file are missing in my cluster, I have to
>> manually kill all java processes on all machines, then I restarted the
>> HDFS, but it took so long time in applying changes in edit log file, so my
>> question is how can I reduce the delay? My understanding is as follows,
>> could someone please give some comments on it?
>>
>> hadoop dfsadmin -safemode enter
>>
>> #save current in-mem data to image file and reset edit log
>> hadoop dfsadmin -saveNamespace
>>
>>
>> --
>> --Anfernee
>>
>
>
--
--Anfernee
Re: how to reduce delay in HDFS restart
Posted by Stanley Shi <ss...@gopivotal.com>.
Do you have a secondary namenode running? Secondary NN is used for this
purpose;
Also, if you have HDFS HA enabled, this problem will also not occur.
Regards,
*Stanley Shi,*
On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com> wrote:
> Hi,
>
> For some reason, all PIDs file are missing in my cluster, I have to
> manually kill all java processes on all machines, then I restarted the
> HDFS, but it took so long time in applying changes in edit log file, so my
> question is how can I reduce the delay? My understanding is as follows,
> could someone please give some comments on it?
>
> hadoop dfsadmin -safemode enter
>
> #save current in-mem data to image file and reset edit log
> hadoop dfsadmin -saveNamespace
>
>
> --
> --Anfernee
>
Re: how to reduce delay in HDFS restart
Posted by Stanley Shi <ss...@gopivotal.com>.
Do you have a secondary namenode running? Secondary NN is used for this
purpose;
Also, if you have HDFS HA enabled, this problem will also not occur.
Regards,
*Stanley Shi,*
On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com> wrote:
> Hi,
>
> For some reason, all PIDs file are missing in my cluster, I have to
> manually kill all java processes on all machines, then I restarted the
> HDFS, but it took so long time in applying changes in edit log file, so my
> question is how can I reduce the delay? My understanding is as follows,
> could someone please give some comments on it?
>
> hadoop dfsadmin -safemode enter
>
> #save current in-mem data to image file and reset edit log
> hadoop dfsadmin -saveNamespace
>
>
> --
> --Anfernee
>
Re: how to reduce delay in HDFS restart
Posted by Stanley Shi <ss...@gopivotal.com>.
Do you have a secondary namenode running? Secondary NN is used for this
purpose;
Also, if you have HDFS HA enabled, this problem will also not occur.
Regards,
*Stanley Shi,*
On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com> wrote:
> Hi,
>
> For some reason, all PIDs file are missing in my cluster, I have to
> manually kill all java processes on all machines, then I restarted the
> HDFS, but it took so long time in applying changes in edit log file, so my
> question is how can I reduce the delay? My understanding is as follows,
> could someone please give some comments on it?
>
> hadoop dfsadmin -safemode enter
>
> #save current in-mem data to image file and reset edit log
> hadoop dfsadmin -saveNamespace
>
>
> --
> --Anfernee
>
Re: how to reduce delay in HDFS restart
Posted by Stanley Shi <ss...@gopivotal.com>.
Do you have a secondary namenode running? Secondary NN is used for this
purpose;
Also, if you have HDFS HA enabled, this problem will also not occur.
Regards,
*Stanley Shi,*
On Tue, Jul 22, 2014 at 7:24 AM, Anfernee Xu <an...@gmail.com> wrote:
> Hi,
>
> For some reason, all PIDs file are missing in my cluster, I have to
> manually kill all java processes on all machines, then I restarted the
> HDFS, but it took so long time in applying changes in edit log file, so my
> question is how can I reduce the delay? My understanding is as follows,
> could someone please give some comments on it?
>
> hadoop dfsadmin -safemode enter
>
> #save current in-mem data to image file and reset edit log
> hadoop dfsadmin -saveNamespace
>
>
> --
> --Anfernee
>