[accumulo-website] branch main updated: Fixes apache/accumulo#1384 documents 2.1.0 GC metadata changes (#257)

[kt...@apache.org]

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The following commit(s) were added to refs/heads/main by this push:
     new 0f03e06  Fixes apache/accumulo#1384 documents 2.1.0 GC metadata changes (#257)
0f03e06 is described below

commit 0f03e0634078cc06c5f803514aa33a8da98c4a38
Author: Keith Turner <kt...@apache.org>
AuthorDate: Tue Jan 19 14:36:22 2021 -0500

    Fixes apache/accumulo#1384 documents 2.1.0 GC metadata changes (#257)
---
 _posts/release/2020-01-19-accumulo-2.1.0.md | 38 +++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/_posts/release/2020-01-19-accumulo-2.1.0.md b/_posts/release/2020-01-19-accumulo-2.1.0.md
new file mode 100644
index 0000000..3a587c6
--- /dev/null
+++ b/_posts/release/2020-01-19-accumulo-2.1.0.md
@@ -0,0 +1,38 @@
+---
+title: Apache Accumulo 2.1.0
+draft: true
+---
+
+** DRAFT RELEASE NOTES **
+
+## Notable Changes
+
+### Fixed GC Metadata hotspots
+
+Prior to this release, Accumulo stored GC file candidates in the metadata table
+using rows of the form `~del<URI>`. This row schema lead to uneven load on
+the metadata table and metadata tablets that were eventually never used. In {%
+ghi 1043 %} the row fromat was changed to `~del<hash(URI)><URI>` resulting in
+even load on the metadata table and even data spread in the tablets. After
+upgrading, there may still be splits in the metadata table using the old row
+format. These splits can be merged away as shown in the example below which
+starts off with splits generated from the old and new row schema. The old
+splits with the prefix `~delhdfs` are merged away.
+
+```
+root@uno> getsplits -t accumulo.metadata 
+2<
+~
+~del55
+~dela7
+~delhdfs://localhost:8020/accumulo/tables/2/default_tablet/F00000a0.rf
+~delhdfs://localhost:8020/accumulo/tables/2/default_tablet/F00000kb.rf
+root@uno> merge -t accumulo.metadata -b ~delhdfs -e ~delhdfs~
+root@uno> getsplits -t accumulo.metadata 
+2<
+~
+~del55
+~dela7
+```
+
+