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ASF GitHub Bot commented on TRAFODION-2521: ------------------------------------------- Github user liuyu000 commented on a diff in the pull request: https://github.com/apache/incubator-trafodion/pull/995#discussion_r107580745 --- Diff: docs/cqd_reference/src/asciidoc/_chapters/query_execution.adoc --- @@ -237,3 +237,54 @@ If you enable small scanner on large size scan incorrectly, then you are likely | *Deprecated In Release* | Not applicable. |=== +<<< +[[scratch-dirs]] +== SCRATCH_DIRS + +[cols="25%h,75%"] +|=== +| *Description* | Allows a CQD specification to override the envvar settings for scatch and temporary file locations, which gives user more flexibility to change scratch directory locations. +| *Values* | +Scratch disk locations for overflow (linux path names). + +Multiple locations can be specified, separated by a colon. For example, /tmp/scratch1:/tmp/scratch2. + +| *Usage* a| + +*Two ways to change scratch directory location permanently*: + +* Specify this location at installation time. + ++ +Currently the scratch directory locations are set at installation time. The layer of scratch and temporary file system that manages the scratch file creation and reads the envvar in $TRAF_HOME/etc/ms.env to determine where to create the scratch files. + ++ +The CQD will override envvar settings, there are two envvar settings: one is STFS_HDD_LOACTION (default), the other is STFS_SSD_LOCATION (SSD disk). + ++ +If the CQD is not set (empty), the envvar setting will work. + ++ +The requirement is that the directories MUST exist on every node and Trafodion user will need permission to write to those directories. If not, an error will be returned when a query involving sort/hash overflow is executed. + +* Set it in sqconfig. + +*One way to change scratch directory location temporarily*: + +* If the scratch directory location is not set at installation time, this CQD is valid only for the duration of the session. + ++ +These settings will not be stored in $TRAF_HOME/etc/ms.env and will override the envvar settings as long as the CQD is in effect. --- End diff -- Got, thanks Dave. :) > Add SCRATCH_DISKS CQD > --------------------- > > Key: TRAFODION-2521 > URL: https://issues.apache.org/jira/browse/TRAFODION-2521 > Project: Apache Trafodion > Issue Type: Documentation > Reporter: Liu Yu > Assignee: Liu Yu > -- This message was sent by Atlassian JIRA (v6.3.15#6346)