Index: src/docbkx/book.xml =================================================================== --- src/docbkx/book.xml (revision 1324714) +++ src/docbkx/book.xml (working copy) @@ -1253,6 +1253,8 @@ map-tasks which will double-write your data to HBase; this is probably not what you want. + See for more information. + Index: src/docbkx/configuration.xml =================================================================== --- src/docbkx/configuration.xml (revision 1324714) +++ src/docbkx/configuration.xml (working copy) @@ -1585,6 +1585,13 @@ For more information about compactions and the compaction file selection process, see +
Speculative Execution + Speculative Execution of MapReduce tasks is on by default, and for HBase clusters it is generally advised to turn off + Speculative Execution at a system-level unless you need it for a specific case, where it can be configured per-job. + Set the properties mapred.map.tasks.speculative.execution and + mapred.reduce.tasks.speculative.execution to false. + +
Other Configurations @@ -1602,6 +1609,7 @@ on the size you need by surveying regionserver UIs; you'll see index block size accounted near the top of the webpage).
+