Repository: incubator-hawq-docs Updated Branches: refs/heads/develop f4bd3ef5a -> 3df5448c8
Note about work_mem Project: http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/repo Commit: http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/commit/bf16a062 Tree: http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/tree/bf16a062 Diff: http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/diff/bf16a062 Branch: refs/heads/develop Commit: bf16a0621bdd5783c5b1400023fa0ab3df9b28e0 Parents: e169704 Author: Jane Beckman <[email protected]> Authored: Wed Oct 12 12:17:36 2016 -0700 Committer: Jane Beckman <[email protected]> Committed: Wed Oct 12 12:17:36 2016 -0700 ---------------------------------------------------------------------- bestpractices/querying_data_bestpractices.html.md.erb | 3 +++ query/query-profiling.html.md.erb | 2 ++ reference/sql/EXPLAIN.html.md.erb | 4 +++- 3 files changed, 8 insertions(+), 1 deletion(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/blob/bf16a062/bestpractices/querying_data_bestpractices.html.md.erb ---------------------------------------------------------------------- diff --git a/bestpractices/querying_data_bestpractices.html.md.erb b/bestpractices/querying_data_bestpractices.html.md.erb index 8a76c6d..7a86176 100644 --- a/bestpractices/querying_data_bestpractices.html.md.erb +++ b/bestpractices/querying_data_bestpractices.html.md.erb @@ -20,6 +20,9 @@ If a query performs poorly, examine its query plan and ask the following questio `Work_mem used: 23430K bytes avg, 23430K bytes max (seg0). Work_mem wanted: 33649K bytes avg, 33649K bytes max (seg0) to lessen workfile I/O affecting 2 workers.` +**Note** +The *work\_mem* property is not configurable. Use resource queues to manage memory use. + The "bytes wanted" message from `EXPLAIN ANALYZE` is based on the amount of data written to work files and is not exact. The minimum `work_mem` needed can differ from the suggested value. http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/blob/bf16a062/query/query-profiling.html.md.erb ---------------------------------------------------------------------- diff --git a/query/query-profiling.html.md.erb b/query/query-profiling.html.md.erb index ca07f6d..8d770d3 100644 --- a/query/query-profiling.html.md.erb +++ b/query/query-profiling.html.md.erb @@ -88,6 +88,8 @@ The estimated startup cost for this plan is `00.00` (no cost) and a total cost o Work_mem wanted: 90K bytes avg, 90K byes max (seg0) to lessen workfile I/O affecting 2 workers. ``` +**Note** +The *work\_mem* property is not configurable. Use resource queues to manage memory use. - The time (in milliseconds) in which the segment that produced the most rows retrieved the first row, and the time taken for that segment to retrieve all rows. The result may omit *<time> to first row* if it is the same as the *<time> to end*. http://git-wip-us.apache.org/repos/asf/incubator-hawq-docs/blob/bf16a062/reference/sql/EXPLAIN.html.md.erb ---------------------------------------------------------------------- diff --git a/reference/sql/EXPLAIN.html.md.erb b/reference/sql/EXPLAIN.html.md.erb index 6d0befd..ca0e908 100644 --- a/reference/sql/EXPLAIN.html.md.erb +++ b/reference/sql/EXPLAIN.html.md.erb @@ -41,7 +41,9 @@ It is important to note that the cost of an upper-level node includes the cost o workfile [seg0] pass 1: 263 groups made from 263 rows ``` - +**Note** +You cannot set the *work\_mem* property. The *work\_mem* property is for information only. + - The time (in milliseconds) it took to retrieve the first row from the segment that produced the most rows, and the total time taken to retrieve all rows from that segment. The `\<time\> to first row` may be omitted if it is the same as the `\<time\> to end`. **Important:**
