Index: src/docbkx/ops_mgt.xml
===================================================================
--- src/docbkx/ops_mgt.xml (revision 1196716)
+++ src/docbkx/ops_mgt.xml (working copy)
@@ -417,6 +417,11 @@
+ Regions
+ Another common question for HBase administrators is determining the right number of regions per
+ RegionServer. This affects both storage and hardware planning. See .
+
+
Index: src/docbkx/performance.xml
===================================================================
--- src/docbkx/performance.xml (revision 1196716)
+++ src/docbkx/performance.xml (working copy)
@@ -140,6 +140,11 @@
The number of regions for an HBase table is driven by the . Also, see the architecture
section on
+ A lower number of regions is preferred, generally in the range of 20 to 200
+ per RegionServer. Adjust the regionsize as appropriate to achieve this number. There
+ are some clusters that set the regionsize to 20Gb, for example, so you may need to
+ experiment with this setting based on your hardware configuration and application needs.
+
Index: src/docbkx/book.xml
===================================================================
--- src/docbkx/book.xml (revision 1196716)
+++ src/docbkx/book.xml (working copy)
@@ -565,6 +565,12 @@
second and third column family in the case where data access is usually column scoped;
i.e. you query one column family or the other but usually not both at the one time.
+ Cardinality of ColumnFamilies
+ Where multiple ColumnFamilies exist in a single table, be aware of the cardinality (i.e., number of rows).
+ If ColumnFamily-A has 1000,000 rows and ColumnFamily-B has 1 billion rows, ColumnFamily-A's data will likely be spread
+ across many, many regions (and RegionServers). This makes mass scans for ColumnFamily-A less efficient.
+
+ Rowkey Design
@@ -972,6 +978,11 @@
+
+ HBase MapReduce Read/Write Example With Multi-Table Output
+ TODO: example for MultiTableOutputFormat.
+
+ HBase MapReduce Summary ExampleThe following example uses HBase as a MapReduce source and sink with a summarization step. This example will
@@ -1575,7 +1586,6 @@
For more information, see the HFile source code.
-
HFile Tool
@@ -1589,7 +1599,13 @@
usage for other things to do with the HFile
tool.
+
+ StoreFile Directory Structure on HDFS
+ For more information of what StoreFiles look like on HDFS with respect to the directory structure, see .
+
+
+
BlocksStoreFiles are composed of blocks. The blocksize is configured on a per-ColumnFamily basis.