hawq-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From dyozie <...@git.apache.org>
Subject [GitHub] incubator-hawq-docs pull request #60: HAWQ-1151 - add ambari procedures
Date Tue, 15 Nov 2016 00:17:35 GMT
Github user dyozie commented on a diff in the pull request:

    https://github.com/apache/incubator-hawq-docs/pull/60#discussion_r87921679
  
    --- Diff: datamgmt/about_statistics.html.md.erb ---
    @@ -142,11 +142,28 @@ There are several options for configuring HAWQ statistics collection.
     
     The statistics target is the size of the `most_common_vals`, `most_common_freqs`, and
`histogram_bounds` arrays for an individual column. By default, the target is 25. The default
target can be changed by setting a server configuration parameter and the target can be set
for any column using the `ALTER TABLE` command. Larger values increase the time needed to
do `ANALYZE`, but may improve the quality of the legacy query optimizer (planner) estimates.
     
    -Set the system default statistics target to a different value by setting the `default_statistics_target`
server configuration parameter. The default value is usually sufficient, and you should only
raise or lower it if your tests demonstrate that query plans improve with the new target.
For example, to raise the default statistics target from 25 to 50 you can use the `hawq config`
utility:
    +Set the system default statistics target to a different value by setting the `default_statistics_target`
server configuration parameter. The default value is usually sufficient, and you should only
raise or lower it if your tests demonstrate that query plans improve with the new target.

     
    -``` shell
    -$ hawq config -c default_statistics_target -v 50
    -```
    +You will perform different procedures to set server configuration parameters for your
whole HAWQ cluster depending upon whether you manage your cluster from the command line or
use Ambari. If you use Ambari to manage your HAWQ cluster, you must ensure that you update
server configuration parameters via the Ambari Web UI only. If you manage your HAWQ cluster
from the command line, you will use the `hawq config` command line utility to set server configuration
parameters.
    +
    +For example, to raise the default statistics target from 25 to 50:
    +
    +1. If you use Ambari to manage your HAWQ cluster:
    +
    +    1. Set the `default_statistics_target` configuration property to `50` via the HAWQ
service **Configs > Advanced > Custom hawq-site** drop down.
    +    2. Select **Service Actions > Restart All** to load the updated configuration.
    +2. If you manage your HAWQ cluster from the command line:
    --- End diff --
    
    Demote to regular para


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastructure@apache.org or file a JIRA ticket
with INFRA.
---

Mime
View raw message