If you experience problems enabling resource groups in Tanzu Greenplum command center, review the following list to ensure prerequisites are met and all of the dependencies are properly configured.
Make sure the /etc/cgconfig.d/gpdb.conf
file contains the objects perm, cpu, and cpuacct. If the document is incorrect and the gp_resource_manager
configuration parameter is set to "group"
, VMware Greenplum can hang at startup.
group gpdb {
perm {
task {
uid = gpadmin;
gid = gpadmin;
}
admin {
uid = gpadmin;
gid = gpadmin;
}
}
cpu {
}
cpuacct {
}
}
On Red Hat 7, make sure you run cgconfigparser -L /etc/cgconfig.d
to parse changes to the /etc/cgconfig.d/gpdb.conf
file. This command must also be set up to run at boot time.
Set the VMware Greenplum gp_resource_manager
server configuration parameter to "group"
and restart VMware Greenplum.
$ gpconfig -c gp_resource_manager -v "group"
$ gpstop -ar
Verify by showing the value of the parameter:
$ gpconfig -s gp_resource_manager
Values on all segments are consistent
GUC : gp_resource_manager
Master value: group
Segment value: group
After installing a VMware Greenplum distribution, the shared_preload_libraries
configuration parameter contains the metrics collector shared library. Make sure this library is still present:
$ gpconfig -s shared_preload_libraries
Values on all segments are consistent
GUC : shared_preload_libraries
Master value: metrics_collector
Segment value: metrics_collector
Check that the shared library exists at $GPHOME/lib/postgresql/metrics_collector.so
. If the library does not exist, make sure you have installed the VMware Greenplum distribution. This extension is not available in the VMware Greenplum Open Source version.
If the shared library file exists in the $GPHOME/lib/postgresql
directory, but not in the shared_preload_libraries
parameter, add it with the gpconfig
command:
$ gpconfig -c shared_preload_libraries -v 'metrics_collector'
Note that adding metrics_collector
to the shared_preload_libraries
parameter does not enable the metrics_collector or gp_wlm extensions, but is a prerequisite for enabling them.
The gpmon user must be able to connect to databases from the Tanzu Greenplum command center host. Make sure to add a host
entry like the following in the $COORDINATOR_DATA_DIRECTORY/pg_hba.conf
file.
host all gpmon <IP_of_host>/32 md5
Check whether the gp_wlm
extension is installed. The extension is added when you click Enable Workloads in the Tanzu Greenplum command center Workload Mgmt view.
$ psql gpperfmon
\dx
gpperfmon=# \dx
List of installed extensions
Name | Version | Schema | Description
-------------------+---------+------------+---------------------------------------
gp_wlm | 0.1 | gpmetrics | Greenplum Workload Manager Extension
metrics_collector | 1.0 | gpmetrics | Greenplum Metrics Collector Extension
plpgsql | 1.0 | pg_catalog | PL/pgSQL procedural language
(3 rows)
Make sure the gpmetrics.workload_config
table and functions are present in the gpperfmon database:
gpperfmon=# \d gpmetrics.workload_config
Table "gpmetrics.workload_config"
Column | Type | Modifiers
----------+---------+-----------
dist_col | integer |
config | json |
Distributed by: (dist_col)
gpperfmon=# \df gpmetrics.*
List of functions
Schema | Name | Result data type | Argument data types | Type
-----------+--------------------------------+------------------+----------------------+--------
gpmetrics | get_workload_config | json | | normal
gpmetrics | metrics_collector_start_worker | void | | normal
gpmetrics | set_workload_config | boolean | wlm_json_config json | normal
(3 rows)
If the gpmetrics.workload_config
table or the functions are not present, dropping and recreating the gp_wlm extension will create them. Note that any assignment rules saved in the gpmetrics.workload_config
table will have to be recreated in Tanzu Greenplum command center.
$ psql gpperfmon
gpperfmon=# DROP EXTENSION gp_wlm;
DROP EXTENSION
gpperfmon=# CREATE EXTENSION gp_wlm;
CREATE EXTENSION