[DOCS] Advise setting vm.overcommit_memory=1 in various places Reusing the same advice under "Known Issues", scalability considerations, and in the Impala + Kerberos section.
Change-Id: Icbfa755e2c9769a8458fd93362769856cf32e301 Reviewed-on: http://gerrit.cloudera.org:8080/7349 Reviewed-by: Mostafa Mokhtar <[email protected]> Tested-by: Impala Public Jenkins Project: http://git-wip-us.apache.org/repos/asf/incubator-impala/repo Commit: http://git-wip-us.apache.org/repos/asf/incubator-impala/commit/db3f3235 Tree: http://git-wip-us.apache.org/repos/asf/incubator-impala/tree/db3f3235 Diff: http://git-wip-us.apache.org/repos/asf/incubator-impala/diff/db3f3235 Branch: refs/heads/master Commit: db3f3235d7c28ff9963e0332b830ecc86f54a505 Parents: cd44381 Author: John Russell <[email protected]> Authored: Fri Jun 30 16:00:30 2017 -0700 Committer: Impala Public Jenkins <[email protected]> Committed: Mon Jul 10 23:06:45 2017 +0000 ---------------------------------------------------------------------- docs/shared/impala_common.xml | 32 ++++++++++++++++++++++++++++++++ docs/topics/impala_kerberos.xml | 8 ++++++++ docs/topics/impala_known_issues.xml | 11 +++++++++++ docs/topics/impala_scalability.xml | 8 ++++++++ 4 files changed, 59 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/db3f3235/docs/shared/impala_common.xml ---------------------------------------------------------------------- diff --git a/docs/shared/impala_common.xml b/docs/shared/impala_common.xml index 6e65c40..2ec2537 100644 --- a/docs/shared/impala_common.xml +++ b/docs/shared/impala_common.xml @@ -1365,6 +1365,38 @@ select c_first_name, c_last_name from customer where lower(trim(c_last_name)) rl <codeph>[email protected]</codeph>, in a Kerberized environment. </p> + <p id="vm_overcommit_memory_intro"> + On a kerberized cluster with high memory utilization, <cmdname>kinit</cmdname> commands executed after + every <codeph>'kerberos_reinit_interval'</codeph> may cause out-of-memory errors, because executing + the command involves a fork of the Impala process. The error looks similar to the following: +<codeblock><![CDATA[ +Failed to obtain Kerberos ticket for principal: <varname>principal_details</varname> +Failed to execute shell cmd: 'kinit -k -t <varname>keytab_details</varname>', +error was: Error(12): Cannot allocate memory +]]> +</codeblock> + </p> + + <p id="vm_overcommit_memory_start"> + The following command changes the <codeph>vm.overcommit_memory</codeph> + setting immediately on a running host. However, this setting is reset + when the host is restarted. +<codeblock><![CDATA[ +echo 1 > /proc/sys/vm/overcommit_memory +]]> +</codeblock> + </p> + <p> + To change the setting in a persistent way, add the following line to the + <filepath>/etc/sysctl.conf</filepath> file: +<codeblock><![CDATA[ +vm.overcommit_memory=1 +]]> +</codeblock> + </p> + <p id="vm_overcommit_memory_end"> + Then run <codeph>sysctl -p</codeph>. No reboot is needed. + </p> <ul> <li id="grant_revoke_single"> Currently, each Impala <codeph>GRANT</codeph> or <codeph>REVOKE</codeph> statement can only grant or http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/db3f3235/docs/topics/impala_kerberos.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_kerberos.xml b/docs/topics/impala_kerberos.xml index 5032fba..5d97aeb 100644 --- a/docs/topics/impala_kerberos.xml +++ b/docs/topics/impala_kerberos.xml @@ -351,4 +351,12 @@ $ chown impala:impala impala-http.keytab</codeblock> </conbody> </concept> + <concept rev="IMPALA-2294" id="kerberos_overhead_memory_usage"> + <title>Kerberos-Related Memory Overhead for Large Clusters</title> + <conbody> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_intro"/> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_start" conrefend="vm_overcommit_memory_end"/> + </conbody> + </concept> + </concept> http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/db3f3235/docs/topics/impala_known_issues.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_known_issues.xml b/docs/topics/impala_known_issues.xml index 30cc245..51920c9 100644 --- a/docs/topics/impala_known_issues.xml +++ b/docs/topics/impala_known_issues.xml @@ -623,6 +623,17 @@ impala hard nproc 262144 </conbody> </concept> + <concept id="IMPALA-2294"> + <title>Kerberos initialization errors due to high memory usage</title> + <conbody> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_intro"/> + <p><b>Bug:</b> <xref keyref="IMPALA-2294">IMPALA-2294</xref></p> + <p><b>Severity:</b> High</p> + <p><b>Workaround:</b></p> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_start" conrefend="vm_overcommit_memory_end"/> + </conbody> + </concept> + <concept id="drop_table_purge_s3a"> <title>DROP TABLE PURGE on S3A table may not delete externally written files</title> <conbody> http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/db3f3235/docs/topics/impala_scalability.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_scalability.xml b/docs/topics/impala_scalability.xml index af61e7a..2ea7603 100644 --- a/docs/topics/impala_scalability.xml +++ b/docs/topics/impala_scalability.xml @@ -887,6 +887,14 @@ so other secure services might be affected temporarily. </conbody> </concept> + <concept rev="IMPALA-2294" id="kerberos_overhead_memory_usage"> + <title>Kerberos-Related Memory Overhead for Large Clusters</title> + <conbody> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_intro"/> + <p conref="../shared/impala_common.xml#common/vm_overcommit_memory_start" conrefend="vm_overcommit_memory_end"/> + </conbody> + </concept> + <concept id="scalability_hotspots" rev="2.5.0 IMPALA-2696"> <title>Avoiding CPU Hotspots for HDFS Cached Data</title> <conbody>
