From 716702a3490a07999d2af817462443e36dd5cdd8 Mon Sep 17 00:00:00 2001 From: bsglz <18031031@qq.com> Date: Mon, 1 Jun 2020 16:38:07 +0800 Subject: [PATCH] HBASE-24455 Correct the doc of "On the number of column families" (#1799) Signed-off-by: Wellington Ramos Chevreuil Signed-off-by: Viraj Jasani --- src/main/asciidoc/_chapters/schema_design.adoc | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/src/main/asciidoc/_chapters/schema_design.adoc b/src/main/asciidoc/_chapters/schema_design.adoc index 2f98e3a73f23..d74c2f1a304b 100644 --- a/src/main/asciidoc/_chapters/schema_design.adoc +++ b/src/main/asciidoc/_chapters/schema_design.adoc @@ -127,8 +127,9 @@ ____ == On the number of column families HBase currently does not do well with anything above two or three column families so keep the number of column families in your schema low. -Currently, flushing and compactions are done on a per Region basis so if one column family is carrying the bulk of the data bringing on flushes, the adjacent families will also be flushed even though the amount of data they carry is small. -When many column families exist the flushing and compaction interaction can make for a bunch of needless i/o (To be addressed by changing flushing and compaction to work on a per column family basis). For more information on compactions, see <>. +Currently, flushing is done on a per Region basis so if one column family is carrying the bulk of the data bringing on flushes, the adjacent families will also be flushed even though the amount of data they carry is small. +When many column families exist the flushing interaction can make for a bunch of needless i/o (To be addressed by changing flushing to work on a per column family basis). +In addition, compactions triggered at table/region level will happen per store too. Try to make do with one column family if you can in your schemas. Only introduce a second and third column family in the case where data access is usually column scoped; i.e.