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Posted to hdfs-user@hadoop.apache.org by Ni...@Dell.com on 2013/01/24 18:28:59 UTC
Support of RHEL version
Hi,
We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
-Nilesh
https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4
Red Hat Linux (RHEL 6.2 and 6.3)
- Poor performance running Hadoop on RHEL 6.2 or later when transparent hugepage compaction is enabled
RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
Severity: Medium (up to 3x performance loss)
Anticipated Resolution: Currently working with Red Hat to resolve for a future RHEL update
Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4>
echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Do you mean Transparent Huge Page Defrag (https://bugzilla.redhat.com/show_bug.cgi?id=805593)?
Do echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
- Alex
On Jan 24, 2013, at 6:46 PM, Dheeren Bebortha <db...@salesforce.com> wrote:
> I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
> Am I reading it right?
> -Dheeren
>
> -----Original Message-----
> From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
> Sent: Thursday, January 24, 2013 9:41 AM
> To: cdh-user@cloudera.org
> Subject: Re: Support of RHEL version
>
> Hi,
>
> Moving the post to cdh-user@cloudera.org
> (https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
> as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
>
> RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
>
> Cheers,
> Alex
>
> On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
>
>> Hi,
>>
>> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>>
>> -Nilesh
>>
>>
>> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
>> +in+CDH4
>>
>>
>> Red Hat Linux (RHEL 6.2 and 6.3)
>> - Poor performance running Hadoop on RHEL 6.2 or later when
>> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
>> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
>> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
>> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
>> Currently working with Red Hat to resolve for a future RHEL update
>> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
>> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
>> ds+in+CDH4> echo never >
>> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>>
>>
>
> --
> Alexander Alten-Lorenz
> http://mapredit.blogspot.com
> German Hadoop LinkedIn Group: http://goo.gl/N8pCF
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Do you mean Transparent Huge Page Defrag (https://bugzilla.redhat.com/show_bug.cgi?id=805593)?
Do echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
- Alex
On Jan 24, 2013, at 6:46 PM, Dheeren Bebortha <db...@salesforce.com> wrote:
> I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
> Am I reading it right?
> -Dheeren
>
> -----Original Message-----
> From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
> Sent: Thursday, January 24, 2013 9:41 AM
> To: cdh-user@cloudera.org
> Subject: Re: Support of RHEL version
>
> Hi,
>
> Moving the post to cdh-user@cloudera.org
> (https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
> as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
>
> RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
>
> Cheers,
> Alex
>
> On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
>
>> Hi,
>>
>> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>>
>> -Nilesh
>>
>>
>> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
>> +in+CDH4
>>
>>
>> Red Hat Linux (RHEL 6.2 and 6.3)
>> - Poor performance running Hadoop on RHEL 6.2 or later when
>> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
>> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
>> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
>> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
>> Currently working with Red Hat to resolve for a future RHEL update
>> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
>> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
>> ds+in+CDH4> echo never >
>> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>>
>>
>
> --
> Alexander Alten-Lorenz
> http://mapredit.blogspot.com
> German Hadoop LinkedIn Group: http://goo.gl/N8pCF
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Do you mean Transparent Huge Page Defrag (https://bugzilla.redhat.com/show_bug.cgi?id=805593)?
Do echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
- Alex
On Jan 24, 2013, at 6:46 PM, Dheeren Bebortha <db...@salesforce.com> wrote:
> I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
> Am I reading it right?
> -Dheeren
>
> -----Original Message-----
> From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
> Sent: Thursday, January 24, 2013 9:41 AM
> To: cdh-user@cloudera.org
> Subject: Re: Support of RHEL version
>
> Hi,
>
> Moving the post to cdh-user@cloudera.org
> (https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
> as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
>
> RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
>
> Cheers,
> Alex
>
> On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
>
>> Hi,
>>
>> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>>
>> -Nilesh
>>
>>
>> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
>> +in+CDH4
>>
>>
>> Red Hat Linux (RHEL 6.2 and 6.3)
>> - Poor performance running Hadoop on RHEL 6.2 or later when
>> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
>> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
>> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
>> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
>> Currently working with Red Hat to resolve for a future RHEL update
>> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
>> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
>> ds+in+CDH4> echo never >
>> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>>
>>
>
> --
> Alexander Alten-Lorenz
> http://mapredit.blogspot.com
> German Hadoop LinkedIn Group: http://goo.gl/N8pCF
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Do you mean Transparent Huge Page Defrag (https://bugzilla.redhat.com/show_bug.cgi?id=805593)?
Do echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
- Alex
On Jan 24, 2013, at 6:46 PM, Dheeren Bebortha <db...@salesforce.com> wrote:
> I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
> Am I reading it right?
> -Dheeren
>
> -----Original Message-----
> From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
> Sent: Thursday, January 24, 2013 9:41 AM
> To: cdh-user@cloudera.org
> Subject: Re: Support of RHEL version
>
> Hi,
>
> Moving the post to cdh-user@cloudera.org
> (https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
> as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
>
> RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
>
> Cheers,
> Alex
>
> On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
>
>> Hi,
>>
>> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>>
>> -Nilesh
>>
>>
>> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
>> +in+CDH4
>>
>>
>> Red Hat Linux (RHEL 6.2 and 6.3)
>> - Poor performance running Hadoop on RHEL 6.2 or later when
>> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
>> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
>> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
>> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
>> Currently working with Red Hat to resolve for a future RHEL update
>> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
>> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
>> ds+in+CDH4> echo never >
>> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>>
>>
>
> --
> Alexander Alten-Lorenz
> http://mapredit.blogspot.com
> German Hadoop LinkedIn Group: http://goo.gl/N8pCF
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
RE: Support of RHEL version
Posted by Dheeren Bebortha <db...@salesforce.com>.
I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
Am I reading it right?
-Dheeren
-----Original Message-----
From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
Sent: Thursday, January 24, 2013 9:41 AM
To: cdh-user@cloudera.org
Subject: Re: Support of RHEL version
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
> +in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when
> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
> Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
> ds+in+CDH4> echo never >
> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
RE: Support of RHEL version
Posted by Dheeren Bebortha <db...@salesforce.com>.
I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
Am I reading it right?
-Dheeren
-----Original Message-----
From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
Sent: Thursday, January 24, 2013 9:41 AM
To: cdh-user@cloudera.org
Subject: Re: Support of RHEL version
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
> +in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when
> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
> Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
> ds+in+CDH4> echo never >
> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
RE: Support of RHEL version
Posted by Dheeren Bebortha <db...@salesforce.com>.
I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
Am I reading it right?
-Dheeren
-----Original Message-----
From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
Sent: Thursday, January 24, 2013 9:41 AM
To: cdh-user@cloudera.org
Subject: Re: Support of RHEL version
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
> +in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when
> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
> Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
> ds+in+CDH4> echo never >
> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
RE: Support of RHEL version
Posted by Dheeren Bebortha <db...@salesforce.com>.
I do not think this is a cdh specific issues. If this is a hbase compaction issue it would be all pervading as long as it si RHEL62 and above!
Am I reading it right?
-Dheeren
-----Original Message-----
From: Alexander Alten-Lorenz [mailto:wget.null@gmail.com]
Sent: Thursday, January 24, 2013 9:41 AM
To: cdh-user@cloudera.org
Subject: Re: Support of RHEL version
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop lists, lets carry forward the discussion on the CDH lists. My response below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds
> +in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when
> transparent hugepage compaction is enabled RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss) Anticipated Resolution:
> Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Aroun
> ds+in+CDH4> echo never >
> /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop
lists, lets carry forward the discussion on the CDH lists. My response
below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when transparent hugepage compaction is enabled
> RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss)
> Anticipated Resolution: Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4>
> echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop
lists, lets carry forward the discussion on the CDH lists. My response
below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when transparent hugepage compaction is enabled
> RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss)
> Anticipated Resolution: Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4>
> echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop
lists, lets carry forward the discussion on the CDH lists. My response
below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when transparent hugepage compaction is enabled
> RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss)
> Anticipated Resolution: Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4>
> echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF
Re: Support of RHEL version
Posted by Alexander Alten-Lorenz <wg...@gmail.com>.
Hi,
Moving the post to cdh-user@cloudera.org
(https://groups.google.com/a/cloudera.org/forum/?fromgroups=#!forum/cdh-user)
as it is CDH4 you specifically are asking about. BCC'd user@hadoop
lists, lets carry forward the discussion on the CDH lists. My response
below.
RHEL 5.x and 6.x wil be supported. Means, RHEL 6.3 too.
Cheers,
Alex
On Jan 24, 2013, at 6:28 PM, <Ni...@Dell.com> wrote:
> Hi,
>
> We are working on implementing Cloudera distributed Hadoop (CDH 4.x) on our environment. Cloudera website talks about supporting RHEL 6.1 version with challenges/issues with the newer version. It also though provides a workaround for it. Wanted to hear from the community on the supported versions of RedHat Linux and any guidance on which version to choose?
>
> -Nilesh
>
>
> https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4
>
>
> Red Hat Linux (RHEL 6.2 and 6.3)
> - Poor performance running Hadoop on RHEL 6.2 or later when transparent hugepage compaction is enabled
> RHEL 6.2 and 6.3 include a feature called "transparent hugepage compaction" which interacts poorly with Hadoop workloads. This can cause a serious performance regression compared to other operating system versions on the same hardware.
> Symptom: top and other system monitoring tools show a large percentage of the CPU usage classified as "system CPU". If system CPU usage is 30% or more of the total CPU usage, your system may be experiencing this issue.
> Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805593
> Severity: Medium (up to 3x performance loss)
> Anticipated Resolution: Currently working with Red Hat to resolve for a future RHEL update
> Workaround: Add the following command to /etc/rc.local to disable transparent hugepage compaction:
> ?<https://ccp.cloudera.com/display/CDH4DOC/Known+Issues+and+Work+Arounds+in+CDH4>
> echo never > /sys/kernel/mm/redhat_transparent_hugepage/defrag
>
>
--
Alexander Alten-Lorenz
http://mapredit.blogspot.com
German Hadoop LinkedIn Group: http://goo.gl/N8pCF