From d052d07b27a166d44fd98ba050a1c37c82aa71b0 Mon Sep 17 00:00:00 2001 From: David Yozie Date: Mon, 6 Nov 2017 08:18:20 -0800 Subject: [PATCH] Docs - updating RG performance note --- gpdb-doc/dita/admin_guide/wlmgmt.xml | 13 +++++++------ .../admin_guide/workload_mgmt_resgroups.xml | 18 ++++++++++-------- 2 files changed, 17 insertions(+), 14 deletions(-) diff --git a/gpdb-doc/dita/admin_guide/wlmgmt.xml b/gpdb-doc/dita/admin_guide/wlmgmt.xml index 178ea69dc1..9140a045b8 100644 --- a/gpdb-doc/dita/admin_guide/wlmgmt.xml +++ b/gpdb-doc/dita/admin_guide/wlmgmt.xml @@ -11,14 +11,15 @@ amount of memory used to execute a query, and the relative amount of CPU devoted to processing a query. Greenplum Database provides two schemes to manage resources - Resource Queues and Resource Groups.

- Significant Greenplum Database performance degradation has been observed + Significant Greenplum Database performance degradation has been observed when enabling resource group-based workload management on RedHat 6.x, CentOS 6.x, and SuSE 11 systems. This issue is caused by a Linux cgroup kernel bug. This kernel bug has been fixed in - CentOS 7.x and Red Hat 7.x systems. The performance problem is mitigated in Red Hat 6 systems - that use kernel version 2.6.32-696 or higher.

SuSE 11 does not have a kernel version that - resolves this issue; resource groups are considered to be an experimental feature on this platform. Resource groups are not supported on SuSE 11 for production - use.

 + CentOS 7.x and Red Hat 7.x systems.

If you use RedHat 6 and the performance with resource + groups is acceptable for your use case, upgrade your kernel to version 2.6.32-696 or higher + to benefit from other fixes to the cgroups implementation.

SuSE 11 does not have a + kernel version that resolves this issue; resource groups are still considered to be an + experimental feature on this platform. Resource groups are not + supported on SuSE 11 for production use.

Either the resource queue or the resource group management scheme can be active in Greenplum Database; both schemes cannot be active at the same time.

Resource queues are enabled by default when you install your Greenplum Database cluster. diff --git a/gpdb-doc/dita/admin_guide/workload_mgmt_resgroups.xml b/gpdb-doc/dita/admin_guide/workload_mgmt_resgroups.xml index 4dfb3d3540..ea13190a07 100644 --- a/gpdb-doc/dita/admin_guide/workload_mgmt_resgroups.xml +++ b/gpdb-doc/dita/admin_guide/workload_mgmt_resgroups.xml @@ -197,14 +197,16 @@ Using Resource Groups - Significant Greenplum Database performance degradation has been observed - when enabling resource group-based workload management on RedHat 6.x, CentOS 6.x, and SuSE - 11 systems. This issue is caused by a Linux cgroup kernel bug. This kernel bug has been - fixed in CentOS 7.x and Red Hat 7.x systems. The performance problem is mitigated in Red Hat - 6 systems that use kernel version 2.6.32-696 or higher.

SuSE 11 does not have a kernel - version that resolves this issue; resource groups are considered to be an experimental - feature on this platform. Resource groups are not supported on - SuSE 11 for production use.

+ Significant Greenplum Database performance degradation has been + observed when enabling resource group-based workload management on RedHat 6.x, CentOS 6.x, + and SuSE 11 systems. This issue is caused by a Linux cgroup kernel bug. This kernel bug has + been fixed in CentOS 7.x and Red Hat 7.x systems.

If you use RedHat 6 and the performance + with resource groups is acceptable for your use case, upgrade your kernel to version + 2.6.32-696 or higher to benefit from other fixes to the cgroups implementation. +

SuSE 11 does not have a kernel version that resolves this issue; resource groups + are still considered to be an experimental feature on this platform. Resource groups are not supported on SuSE 11 for production + use.
Prerequisite

Greenplum Database resource groups use Linux Control Groups (cgroups) to manage CPU -- GitLab