diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/build.yml
similarity index 79%
rename from .github/workflows/ubuntu.yml
rename to .github/workflows/build.yml
index cd90bbeac..1e57afa5a 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/build.yml
@@ -1,4 +1,4 @@
-name: Ubuntu
+name: Build
 on: [push, pull_request]
 jobs:
   build:
@@ -38,6 +38,16 @@ jobs:
           # `service mysql restart` fails.
           - {os: ubuntu-20.04, ruby: 2.4, db: mysql80, allow-failure: true}
           - {os: ubuntu-18.04, ruby: 'head', db: '', allow-failure: true}
+          # db: A DB's brew package name in macOS case.
+          #     Set a name "db: 'name@X.Y'" when using an old version.
+          # MariaDB lastet version
+          # Allow failure due to the following test failures.
+          # https://github.com/brianmario/mysql2/issues/965
+          # https://github.com/brianmario/mysql2/issues/1152
+          - {os: macos-latest, ruby: 2.4, db: mariadb, allow-failure: true}
+          # MySQL latest version
+          # Allow failure due to the issue #1165.
+          - {os: macos-latest, ruby: 2.4, db: mysql, allow-failure: true}
       # On the fail-fast: true, it cancels all in-progress jobs
       # if any matrix job fails unlike Travis fast_finish.
       fail-fast: false
diff --git a/.travis.yml b/.travis.yml
index dfcee6e0c..03129303b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -49,14 +49,5 @@ matrix:
       addons:
         hosts:
           - mysql2gem.example.com
-    - os: osx
-      rvm: 2.4
-      env: DB=mysql56
-      addons:
-        hosts:
-          - mysql2gem.example.com
   fast_finish: true
   allow_failures:
-    - os: osx
-      rvm: 2.4
-      env: DB=mysql56
diff --git a/.travis_setup.sh b/.travis_setup.sh
index 50ecd5e48..09f25a1d2 100644
--- a/.travis_setup.sh
+++ b/.travis_setup.sh
@@ -2,23 +2,24 @@
 
 set -eux
 
-CHANGED_PWD=false
-# Change the password recreating the root user on mariadb < 10.2
+# Change the password to be empty.
+CHANGED_PASSWORD=false
+# Change the password to be empty, recreating the root user on mariadb < 10.2
 # where ALTER USER is not available.
 # https://stackoverflow.com/questions/56052177/
-CHANGED_PWD_BY_RECREATE=false
+CHANGED_PASSWORD_BY_RECREATE=false
 
 # Install the default used DB if DB is not set.
-if [[ -n ${GITHUB_ACTION-} && -z ${DB-} ]]; then
+if [[ -n ${GITHUB_ACTIONS-} && -z ${DB-} ]]; then
   if command -v lsb_release > /dev/null; then
     case "$(lsb_release -cs)" in
     xenial | bionic)
       sudo apt-get install -qq mysql-server-5.7 mysql-client-core-5.7 mysql-client-5.7
-      CHANGED_PWD=true
+      CHANGED_PASSWORD=true
       ;;
     focal)
       sudo apt-get install -qq mysql-server-8.0 mysql-client-core-8.0 mysql-client-8.0
-      CHANGED_PWD=true
+      CHANGED_PASSWORD=true
       ;;
     *)
       ;;
@@ -34,20 +35,20 @@ fi
 # Install MySQL 5.7 if DB=mysql57
 if [[ -n ${DB-} && x$DB =~ ^xmysql57 ]]; then
   sudo bash .travis_mysql57.sh
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
 # Install MySQL 8.0 if DB=mysql80
 if [[ -n ${DB-} && x$DB =~ ^xmysql80 ]]; then
   sudo bash .travis_mysql80.sh
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
 # Install MariaDB client headers after Travis CI fix for MariaDB 10.2 broke earlier 10.x
 if [[ -n ${DB-} && x$DB =~ ^xmariadb10.0 ]]; then
-  if [[ -n ${GITHUB_ACTION-} ]]; then
+  if [[ -n ${GITHUB_ACTIONS-} ]]; then
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.0 libmariadb2
-    CHANGED_PWD_BY_RECREATE=true
+    CHANGED_PASSWORD_BY_RECREATE=true
   else
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' libmariadbclient-dev
   fi
@@ -55,9 +56,9 @@ fi
 
 # Install MariaDB client headers after Travis CI fix for MariaDB 10.2 broke earlier 10.x
 if [[ -n ${DB-} && x$DB =~ ^xmariadb10.1 ]]; then
-  if [[ -n ${GITHUB_ACTION-} ]]; then
+  if [[ -n ${GITHUB_ACTIONS-} ]]; then
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.1 libmariadb-dev
-    CHANGED_PWD_BY_RECREATE=true
+    CHANGED_PASSWORD_BY_RECREATE=true
   else
     sudo apt-get install -y -o Dpkg::Options::='--force-confnew' libmariadbclient-dev
   fi
@@ -70,16 +71,29 @@ if [[ -n ${DB-} && x$DB =~ ^xmariadb10.2 ]]; then
 fi
 
 # Install MariaDB 10.3 if DB=mariadb10.3
-if [[ -n ${GITHUB_ACTION-} && -n ${DB-} && x$DB =~ ^xmariadb10.3 ]]; then
+if [[ -n ${GITHUB_ACTIONS-} && -n ${DB-} && x$DB =~ ^xmariadb10.3 ]]; then
   sudo apt-get install -y -o Dpkg::Options::='--force-confnew' mariadb-server mariadb-server-10.3 libmariadb-dev
-  CHANGED_PWD=true
+  CHANGED_PASSWORD=true
 fi
 
-# Install MySQL if OS=darwin
+# Install MySQL/MariaDB if OS=darwin
 if [[ x$OSTYPE =~ ^xdarwin ]]; then
-  brew update
-  brew install "$DB" mariadb-connector-c
-  $(brew --prefix "$DB")/bin/mysql.server start
+  brew update > /dev/null
+
+  # Check available packages.
+  for KEYWORD in mysql mariadb; do
+    brew search "${KEYWORD}"
+  done
+
+  brew info "$DB"
+  brew install "$DB"
+  DB_PREFIX="$(brew --prefix "${DB}")"
+  export PATH="${DB_PREFIX}/bin:${PATH}"
+  export LDFLAGS="-L${DB_PREFIX}/lib"
+  export CPPFLAGS="-I${DB_PREFIX}/include"
+
+  mysql.server start
+  CHANGED_PASSWORD_BY_RECREATE=true
 fi
 
 # TODO: get SSL working on OS X in Travis
@@ -88,14 +102,12 @@ if ! [[ x$OSTYPE =~ ^xdarwin ]]; then
   sudo service mysql restart
 fi
 
-# Print the MySQL version and create the test DB
-if [[ x$OSTYPE =~ ^xdarwin ]]; then
-  $(brew --prefix "$DB")/bin/mysqld --version
-  $(brew --prefix "$DB")/bin/mysql -u root -e 'CREATE DATABASE IF NOT EXISTS test'
-else
-  mysqld --version
+mysqld --version
 
-  if [[ -n ${GITHUB_ACTION-} && -f /etc/mysql/debian.cnf ]]; then
+MYSQL_OPTS=''
+DB_SYS_USER=root
+if ! [[ x$OSTYPE =~ ^xdarwin ]]; then
+  if [[ -n ${GITHUB_ACTIONS-} && -f /etc/mysql/debian.cnf ]]; then
     MYSQL_OPTS='--defaults-extra-file=/etc/mysql/debian.cnf'
     # Install from packages in OS official packages.
     if sudo grep -q debian-sys-maint /etc/mysql/debian.cnf; then
@@ -105,25 +117,20 @@ else
       # xenial
       DB_SYS_USER=root
     fi
-  else
-    # Install from official mysql packages.
-    MYSQL_OPTS=''
-    DB_SYS_USER=root
   fi
+fi
 
-  if [ "${CHANGED_PWD}" = true ]; then
-    # https://www.percona.com/blog/2016/03/16/change-user-password-in-mysql-5-7-with-plugin-auth_socket/
-    sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" \
-      -e "ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY ''"
-  elif [ "${CHANGED_PWD_BY_RECREATE}" = true ]; then
-    sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" <<SQL
+if [ "${CHANGED_PASSWORD}" = true ]; then
+  # https://www.percona.com/blog/2016/03/16/change-user-password-in-mysql-5-7-with-plugin-auth_socket/
+  sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" \
+    -e "ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY ''"
+elif [ "${CHANGED_PASSWORD_BY_RECREATE}" = true ]; then
+  sudo mysql ${MYSQL_OPTS} -u "${DB_SYS_USER}" <<SQL
 DROP USER 'root'@'localhost';
 CREATE USER 'root'@'localhost' IDENTIFIED BY '';
 GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION;
 FLUSH PRIVILEGES;
 SQL
-  fi
-
-  # IF NOT EXISTS is mariadb-10+ only - https://mariadb.com/kb/en/mariadb/comment-syntax/
-  mysql -u root -e 'CREATE DATABASE /*M!50701 IF NOT EXISTS */ test'
 fi
+
+mysql -u root -e 'CREATE DATABASE IF NOT EXISTS test'
diff --git a/spec/mysql2/client_spec.rb b/spec/mysql2/client_spec.rb
index 0bdd65c9f..fcc8cc44e 100644
--- a/spec/mysql2/client_spec.rb
+++ b/spec/mysql2/client_spec.rb
@@ -629,7 +629,7 @@ def run_gc
         end
 
         # the query ran uninterrupted
-        expect(mark.fetch(:QUERY_END) - mark.fetch(:QUERY_START)).to be_within(0.1).of(query_time)
+        expect(mark.fetch(:QUERY_END) - mark.fetch(:QUERY_START)).to be_within(0.2).of(query_time)
         # signals fired while the query was running
         expect(mark.fetch(:USR1)).to be_between(mark.fetch(:QUERY_START), mark.fetch(:QUERY_END))
       end
@@ -708,7 +708,7 @@ def run_gc
 
         # This check demonstrates that the threads are sleeping concurrently:
         # In the serial case, the difference would be a multiple of sleep time
-        expect(stop - start).to be_within(0.1).of(sleep_time)
+        expect(stop - start).to be_within(0.2).of(sleep_time)
 
         expect(values).to match_array(threads.map(&:object_id))
       end