From d7d320d372962a9938f9fa25c1b611d2e40b3760 Mon Sep 17 00:00:00 2001
From: Noah Levitt <nlevitt@archive.org>
Date: Tue, 18 Dec 2018 10:31:33 -0800
Subject: [PATCH] un-threadlocal the HConnection

realized that we're leaking zookeeper connections, and it might be
because the HConnection has been thread local, which probably means that
at shutdown only one of the possibly many connections is cleaned up

zookeeper by default allows 60 connections per client and it looks
likely that we start having trouble when we hit that limit
---
 .../modules/recrawl/hbase/HBaseTable.java       | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/contrib/src/main/java/org/archive/modules/recrawl/hbase/HBaseTable.java b/contrib/src/main/java/org/archive/modules/recrawl/hbase/HBaseTable.java
index eb33b2c8..3032c2df 100644
--- a/contrib/src/main/java/org/archive/modules/recrawl/hbase/HBaseTable.java
+++ b/contrib/src/main/java/org/archive/modules/recrawl/hbase/HBaseTable.java
@@ -42,7 +42,7 @@ public class HBaseTable extends HBaseTableBean {
             Logger.getLogger(HBaseTable.class.getName());
 
     protected boolean create = false;
-    protected ThreadLocal<HConnection> hconn = new ThreadLocal<HConnection>();
+    protected HConnection hconn = null;
     protected ThreadLocal<HTableInterface> htable = new ThreadLocal<HTableInterface>();
 
     public boolean getCreate() {
@@ -56,11 +56,11 @@ public class HBaseTable extends HBaseTableBean {
     public HBaseTable() {
     }
 
-    protected HConnection hconnection() throws IOException {
-        if (hconn.get() == null) {
-            hconn.set(HConnectionManager.createConnection(hbase.configuration()));
+    protected synchronized HConnection hconnection() throws IOException {
+        if (hconn == null) {
+            hconn = HConnectionManager.createConnection(hbase.configuration());
         }
-        return hconn.get();
+        return hconn;
     }
 
     protected HTableInterface htable() throws IOException {
@@ -138,13 +138,14 @@ public class HBaseTable extends HBaseTableBean {
             htable.remove();
         }
 
-        if (hconn.get() != null) {
+        if (hconn != null) {
             try {
-                hconn.get().close();
+                hconn.close();
             } catch (IOException e) {
                 logger.log(Level.WARNING, "hconn.close() threw " + e, e);
             }
-            hconn.remove();
+            // HConnectionManager.deleteStaleConnection(hconn);
+            hconn = null;
         }
 
         hbase.reset();