diff --git a/src/main/asciidoc/_chapters/upgrading.adoc b/src/main/asciidoc/_chapters/upgrading.adoc index 9552024bf60..b0a55659e20 100644 --- a/src/main/asciidoc/_chapters/upgrading.adoc +++ b/src/main/asciidoc/_chapters/upgrading.adoc @@ -226,6 +226,17 @@ NOTE: You cannot do a <> from 0.96.x to 1 There are no known issues running a <> from HBase 0.98.x to HBase 1.0.0. +[[upgrade1.0.scanner.caching]] +==== Scanner Caching has Changed +.From 0.98.x to 1.x +In hbase-1.x, the default Scan caching 'number of rows' changed. +Where in 0.98.x, it defaulted to 100, in later HBase versions, the +default became Integer.MAX_VALUE. Not setting a cache size can make +for Scans that run for a long time server-side, especially if +they are running with stringent filtering. See +link:https://issues.apache.org/jira/browse/HBASE-16973[Revisiting default value for hbase.client.scanner.caching]; +for further discussion. + [[upgrade1.0.from.0.94]] ==== Upgrading to 1.0 from 0.94 You cannot rolling upgrade from 0.94.x to 1.x.x. You must stop your cluster, install the 1.x.x software, run the migration described at <> (substituting 1.x.x. wherever we make mention of 0.96.x in the section below), and then restart. Be sure to upgrade your ZooKeeper if it is a version less than the required 3.4.x.