postgrespro · dmitry-lipetsk · Jul 15, 2026 · Jul 15, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -134,6 +134,9 @@ jobs:
     env:
       BASE_SIGN: "${{ matrix.platform }}-${{ matrix.case_suffix }}"
 
+      DOCKER_HIGHLOAD_FLAGS: >-
+        --init
+
     steps:
     - name: Prepare variables
       run: |
@@ -170,6 +173,7 @@ jobs:
         # "- sleep infinity" is a right command. Docker ignores "-" and runs "sleep infinity".
         #
         docker run -d -t \
+          ${{ env.DOCKER_HIGHLOAD_FLAGS }} \
           --network ${{ env.RUN_CFG__NETWORK_NAME }} \
           --name ${{ env.RUN_CFG__MACHINE2_NAME }} \
           "${{ env.RUN_CFG__DOCKER_IMAGE_NAME }}" \
@@ -217,6 +221,7 @@ jobs:
         # Pass environment variables so Python tests know where to start.
         # Added the --rm flag so that the container is automatically deleted after the tests are completed
         docker run --rm -t \
+          ${{ env.DOCKER_HIGHLOAD_FLAGS }} \
           --network ${{ env.RUN_CFG__NETWORK_NAME }} \
           --name ${{ env.RUN_CFG__MACHINE1_NAME }} \
           -v ${{ github.workspace }}/${{ env.RUN_CFG__LOGS_DIR }}:/home/test/testgres/logs \

diff --git a/Dockerfile--alpine.tmpl b/Dockerfile--alpine.tmpl
@@ -13,6 +13,10 @@ RUN apk add --no-cache \
     sudo \
     git
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/ssh/sshd_config
+
 ENV PYTHON_BINARY=python3
 
 # --------------------------------------------- base2
@@ -43,7 +47,16 @@ RUN echo "test:*" | chpasswd -e
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    # echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 #
 # \"$@\"
@@ -69,11 +82,6 @@ if [ ! -f /home/test/.ssh/id_rsa ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su test -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\"; \
-su test -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\"; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su test -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\"; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \

diff --git a/Dockerfile--altlinux_10.tmpl b/Dockerfile--altlinux_10.tmpl
@@ -15,6 +15,10 @@ RUN apt-get update && apt-get install -y \
     git \
     && apt-get clean
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/openssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/openssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/openssh/sshd_config
+
 # --------------------------------------------- base2_with_python-3
 FROM base1 AS base2_with_python-3
 
@@ -36,21 +40,23 @@ RUN adduser test -G wheel
 # It enables execution of "sudo service ssh start" without password
 RUN echo "test ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers
 
-#
-# Altlinux 10 and 11 too slowly create a new SSH connection (x6).
-#
-# AI: SPEED UP SSH 6 TIMES (REMOVE REVERSE DNS LOOKUP TIMEOUTS)
-#
-RUN echo "UseDNS no" >> /etc/openssh/sshd_config
-
 COPY --chown=test:test . /home/test/testgres
 WORKDIR /home/test/testgres
 
 ENV LANG=C.UTF-8
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 #
 # \"$@\"
@@ -60,7 +66,7 @@ RUN chmod 700 /home/test/ && \
 ENTRYPOINT ["sh", "-c", " \
     set -eux; \
     echo 'SYSTEM START: PREPARING SSH'; \
-    /usr/sbin/sshd; \
+    (ulimit -n 1024 && /usr/sbin/sshd); \
     ls -la /home/test/.ssh/; \
     \"$@\" \
 ", "DUMMY-DUMMY-DUMMY"]
@@ -76,11 +82,6 @@ if [ ! -f /home/test/.ssh/id_rsa ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\" test; \
-su -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\" test; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\" test; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \

diff --git a/Dockerfile--altlinux_11.tmpl b/Dockerfile--altlinux_11.tmpl
@@ -16,6 +16,10 @@ RUN apt-get update && apt-get install -y \
     procps \
     && apt-get clean
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/openssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/openssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/openssh/sshd_config
+
 # --------------------------------------------- base2_with_python-3
 FROM base1 AS base2_with_python-3
 
@@ -37,21 +41,23 @@ RUN adduser test -G wheel
 # It enables execution of "sudo service ssh start" without password
 RUN echo "test ALL=(ALL:ALL) NOPASSWD: ALL" >> /etc/sudoers
 
-#
-# Altlinux 10 and 11 too slowly create a new SSH connection (x6).
-#
-# AI: SPEED UP SSH 6 TIMES (REMOVE REVERSE DNS LOOKUP TIMEOUTS)
-#
-RUN echo "UseDNS no" >> /etc/openssh/sshd_config
-
 COPY --chown=test:test . /home/test/testgres
 WORKDIR /home/test/testgres
 
 ENV LANG=C.UTF-8
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 #
 # \"$@\"
@@ -61,7 +67,7 @@ RUN chmod 700 /home/test/ && \
 ENTRYPOINT ["sh", "-c", " \
     set -eux; \
     echo 'SYSTEM START: PREPARING SSH'; \
-    /usr/sbin/sshd; \
+    (ulimit -n 1024 && /usr/sbin/sshd); \
     ls -la /home/test/.ssh/; \
     \"$@\" \
 ", "DUMMY-DUMMY-DUMMY"]
@@ -77,11 +83,6 @@ if [ ! -f /home/test/.ssh/id_rsa ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\" test; \
-su -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\" test; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\" test; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \

diff --git a/Dockerfile--astralinux_1_7.tmpl b/Dockerfile--astralinux_1_7.tmpl
@@ -15,6 +15,10 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     git \
     && rm -rf /var/lib/apt/lists/*
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/ssh/sshd_config
+
 # --------------------------------------------- base2_with_python-3
 FROM base1 AS base2_with_python-3
 
@@ -51,7 +55,16 @@ ENV LANG=C.UTF-8
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 #
 # \"$@\"
@@ -77,11 +90,6 @@ if [ ! -f /home/test/.ssh/id_rsa ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su test -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\"; \
-su test -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\"; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su test -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\"; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \

diff --git a/Dockerfile--rockylinux_10.tmpl b/Dockerfile--rockylinux_10.tmpl
@@ -15,7 +15,7 @@ RUN dnf install -y 'dnf-command(config-manager)' && \
 
 # Consolidating system utilities, including iproute (to prevent tests from failing)
 # Added the --allowerasing flag so dnf can seamlessly replace curl-minimal with full-fledged curl
-RUN dnf install -y --allowerasing \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 --allowerasing \
     sudo \
     curl \
     ca-certificates \
@@ -29,6 +29,10 @@ RUN dnf install -y --allowerasing \
     git \
     && dnf clean all
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/ssh/sshd_config
+
 # In RHEL 9/10, to generate host keys inside Docker, you need to call this binary
 RUN /usr/libexec/openssh/sshd-keygen rsa && \
     /usr/libexec/openssh/sshd-keygen ed25519
@@ -37,7 +41,7 @@ RUN /usr/libexec/openssh/sshd-keygen rsa && \
 FROM base1 AS base2_with_python-3
 
 # Rocky 9/10 installs python3.9 or higher (depending on the repository)
-RUN dnf install -y \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 --allowerasing \
     python3 \
     python3-devel \
     && dnf clean all
@@ -67,7 +71,16 @@ ENV LANG=C.UTF-8
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 # Our ENTRYPOINT with a stub
 ENTRYPOINT ["sh", "-c", " \
@@ -90,11 +103,6 @@ if [ ! -f /home/test/.ssh/id_ed25519 ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su test -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\"; \
-su test -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\"; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su test -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\"; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \

diff --git a/Dockerfile--rockylinux_8.tmpl b/Dockerfile--rockylinux_8.tmpl
@@ -15,7 +15,7 @@ RUN dnf install -y 'dnf-command(config-manager)' && \
     dnf config-manager --set-enabled powertools
 
 # Combine the installation of system utilities, SSH into one layer
-RUN dnf install -y \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 \
     sudo \
     curl \
     ca-certificates \
@@ -29,10 +29,14 @@ RUN dnf install -y \
     iproute \
     && dnf clean all
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/ssh/sshd_config
+
 # --------------------------------------------- base2_with_python-3
 FROM base1 AS base2_with_python-3
 
-RUN dnf install -y \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 \
     python39 \
     python39-devel \
     && dnf clean all

diff --git a/Dockerfile--rockylinux_9.tmpl b/Dockerfile--rockylinux_9.tmpl
@@ -15,7 +15,7 @@ RUN dnf install -y 'dnf-command(config-manager)' && \
 
 # Consolidating system utilities, including iproute (to prevent tests from failing)
 # Added the --allowerasing flag so dnf can seamlessly replace curl-minimal with full-fledged curl
-RUN dnf install -y --allowerasing \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 --allowerasing \
     sudo \
     curl \
     ca-certificates \
@@ -29,6 +29,10 @@ RUN dnf install -y --allowerasing \
     git \
     && dnf clean all
 
+RUN sed -i 's/#MaxStartups 10:30:100/MaxStartups 2000:30:2000/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxSessions 10/MaxSessions 500/' /etc/ssh/sshd_config && \
+    sed -i 's/#MaxAuthTries 6/MaxAuthTries 20/' /etc/ssh/sshd_config
+
 # In RHEL 9/10, to generate host keys inside Docker, you need to call this binary
 RUN /usr/libexec/openssh/sshd-keygen rsa && \
     /usr/libexec/openssh/sshd-keygen ed25519
@@ -37,7 +41,7 @@ RUN /usr/libexec/openssh/sshd-keygen rsa && \
 FROM base1 AS base2_with_python-3
 
 # Rocky 9/10 installs python3.9 or higher (depending on the repository)
-RUN dnf install -y \
+RUN dnf install -y --setopt=retries=10 --setopt=max_parallel_downloads=10 --allowerasing \
     python3 \
     python3-devel \
     && dnf clean all
@@ -67,7 +71,16 @@ ENV LANG=C.UTF-8
 
 RUN chmod 700 /home/test/ && \
     mkdir -p /home/test/.ssh && \
-    chown -R test:test /home/test/.ssh
+    echo 'Host *' > /home/test/.ssh/config && \
+    echo '    ControlMaster auto' >> /home/test/.ssh/config && \
+    echo '    ControlPath /home/test/.ssh/master-%r@%h:%p' >> /home/test/.ssh/config && \
+    echo '    ControlPersist 30m' >> /home/test/.ssh/config && \
+    echo '    StrictHostKeyChecking no' >> /home/test/.ssh/config && \
+    echo '    UserKnownHostsFile /dev/null' >> /home/test/.ssh/config && \
+    echo '    GSSAPIAuthentication no' >> /home/test/.ssh/config && \
+    chown -R test:test /home/test/.ssh && \
+    chmod 700 /home/test/.ssh && \
+    chmod 600 /home/test/.ssh/config
 
 # Our ENTRYPOINT with a stub
 ENTRYPOINT ["sh", "-c", " \
@@ -90,11 +103,6 @@ if [ ! -f /home/test/.ssh/id_ed25519 ]; then \
     chmod 600 /home/test/.ssh/authorized_keys; \
 fi; \
 ls -la /home/test/.ssh/; \
-su test -c \"ssh-keyscan -H localhost >> /home/test/.ssh/known_hosts\"; \
-su test -c \"ssh-keyscan -H 127.0.0.1 >> /home/test/.ssh/known_hosts\"; \
-if [ -n \"${TEST_CFG__REMOTE_HOST:-}\" ]; then \
-    su test -c \"ssh-keyscan -H ${TEST_CFG__REMOTE_HOST} >> /home/test/.ssh/known_hosts\"; \
-fi; \
 if [ -n \"${TEST_CFG__REMOTE_SSH_KEY:-}\" ]; then \
     cp \"${TEST_CFG__REMOTE_SSH_KEY}\" \"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \
     export TEST_CFG__REMOTE_SSH_KEY=\"${TEST_CFG__REMOTE_SSH_KEY}_ci\"; \