Add cli help for new caching parameters patch by vijay; reviewed by slebresne for CASSANDRA-3984
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/9829e2be Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/9829e2be Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/9829e2be Branch: refs/heads/cassandra-1.1 Commit: 9829e2be58702ea4e1897805b92712b867b6ced2 Parents: e58540f Author: Sylvain Lebresne <sylv...@datastax.com> Authored: Tue Mar 6 11:46:09 2012 +0100 Committer: Sylvain Lebresne <sylv...@datastax.com> Committed: Tue Mar 6 11:46:09 2012 +0100 ---------------------------------------------------------------------- .../org/apache/cassandra/cli/CliHelp.yaml | 29 +++++++++++++-- 1 files changed, 25 insertions(+), 4 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/cassandra/blob/9829e2be/src/resources/org/apache/cassandra/cli/CliHelp.yaml ---------------------------------------------------------------------- diff --git a/src/resources/org/apache/cassandra/cli/CliHelp.yaml b/src/resources/org/apache/cassandra/cli/CliHelp.yaml index 72a8bb6..9044fc0 100644 --- a/src/resources/org/apache/cassandra/cli/CliHelp.yaml +++ b/src/resources/org/apache/cassandra/cli/CliHelp.yaml @@ -524,10 +524,10 @@ commands: create column family Super4 with column_type = 'Super' and comparator = 'AsciiType' - and rows_cached = 10000; + and caching='ALL'; create column family Standard3 with comparator = 'LongType' - and rows_cached = 10000; + and caching='ALL'; create column family Standard4 with comparator = AsciiType and column_metadata = @@ -709,6 +709,27 @@ commands: It is also valid to specify the fully-qualified class name to a class that extends org.apache.cassandra.db.marshal.AbstractType. + - caching: Enable/Disable caching for the column family. + + There is 2 kind of caches: key cache and row cache. A column family + can be set to use no cache, only one of them or both. + + A key cache hit saves 1 seek while a row cache hit avoids disk + completely (saving at least 2 seeks). However the row cache holds + entire rows and is thus much more space-intensive. Also, since full + rows are stored, row cache should be used only for column families + whose rows are small. + + Note: the global memory size of both cache can be set in the + configuration file (yaml) or through JMX (though it isn't persisted + across restarts in that latter case). + + Supported values are: + - ALL (Enable row cache and key Cache) + - KEYS_ONLY + - ROWS_ONLY + - NONE; + - max_compaction_threshold: The maximum number of SSTables allowed before a minor compaction is forced. Default is 32, setting to 0 disables minor compactions. @@ -748,9 +769,9 @@ commands: Examples: update column family Super4 with column_type = 'Super' - and rows_cached = 10000; + and caching='ALL'; update column family Standard3 - with rows_cached = 10000; + and caching='ALL'; update column family Standard4 with column_metadata = [{