diff -r 195dcc10b3d7 -r 65b3ef162b39 contrib/automation/hgautomation/cli.py
--- a/contrib/automation/hgautomation/cli.py	Tue Apr 23 21:57:32 2019 -0700
+++ b/contrib/automation/hgautomation/cli.py	Sat Apr 27 11:48:26 2019 -0700
@@ -8,12 +8,15 @@
 # no-check-code because Python 3 native.
 
 import argparse
+import concurrent.futures as futures
 import os
 import pathlib
+import time
 
 from . import (
     aws,
     HGAutomation,
+    linux,
     windows,
 )
 
@@ -22,6 +25,33 @@
 DIST_PATH = SOURCE_ROOT / 'dist'
 
 
+def bootstrap_linux_dev(hga: HGAutomation, aws_region, distros=None,
+                        parallel=False):
+    c = hga.aws_connection(aws_region)
+
+    if distros:
+        distros = distros.split(',')
+    else:
+        distros = sorted(linux.DISTROS)
+
+    # TODO There is a wonky interaction involving KeyboardInterrupt whereby
+    # the context manager that is supposed to terminate the temporary EC2
+    # instance doesn't run. Until we fix this, make parallel building opt-in
+    # so we don't orphan instances.
+    if parallel:
+        fs = []
+
+        with futures.ThreadPoolExecutor(len(distros)) as e:
+            for distro in distros:
+                fs.append(e.submit(aws.ensure_linux_dev_ami, c, distro=distro))
+
+            for f in fs:
+                f.result()
+    else:
+        for distro in distros:
+            aws.ensure_linux_dev_ami(c, distro=distro)
+
+
 def bootstrap_windows_dev(hga: HGAutomation, aws_region):
     c = hga.aws_connection(aws_region)
     image = aws.ensure_windows_dev_ami(c)
@@ -107,6 +137,37 @@
     aws.remove_resources(c)
 
 
+def run_tests_linux(hga: HGAutomation, aws_region, instance_type,
+                    python_version, test_flags, distro, filesystem):
+    c = hga.aws_connection(aws_region)
+    image = aws.ensure_linux_dev_ami(c, distro=distro)
+
+    t_start = time.time()
+
+    ensure_extra_volume = filesystem not in ('default', 'tmpfs')
+
+    with aws.temporary_linux_dev_instances(
+        c, image, instance_type,
+        ensure_extra_volume=ensure_extra_volume) as insts:
+
+        instance = insts[0]
+
+        linux.prepare_exec_environment(instance.ssh_client,
+                                       filesystem=filesystem)
+        linux.synchronize_hg(SOURCE_ROOT, instance, '.')
+        t_prepared = time.time()
+        linux.run_tests(instance.ssh_client, python_version,
+                        test_flags)
+        t_done = time.time()
+
+    t_setup = t_prepared - t_start
+    t_all = t_done - t_start
+
+    print(
+        'total time: %.1fs; setup: %.1fs; tests: %.1fs; setup overhead: %.1f%%'
+        % (t_all, t_setup, t_done - t_prepared, t_setup / t_all * 100.0))
+
+
 def run_tests_windows(hga: HGAutomation, aws_region, instance_type,
                       python_version, arch, test_flags):
     c = hga.aws_connection(aws_region)
@@ -138,6 +199,21 @@
     subparsers = parser.add_subparsers()
 
     sp = subparsers.add_parser(
+        'bootstrap-linux-dev',
+        help='Bootstrap Linux development environments',
+    )
+    sp.add_argument(
+        '--distros',
+        help='Comma delimited list of distros to bootstrap',
+    )
+    sp.add_argument(
+        '--parallel',
+        action='store_true',
+        help='Generate AMIs in parallel (not CTRL-c safe)'
+    )
+    sp.set_defaults(func=bootstrap_linux_dev)
+
+    sp = subparsers.add_parser(
         'bootstrap-windows-dev',
         help='Bootstrap the Windows development environment',
     )
@@ -233,6 +309,41 @@
     sp.set_defaults(func=purge_ec2_resources)
 
     sp = subparsers.add_parser(
+        'run-tests-linux',
+        help='Run tests on Linux',
+    )
+    sp.add_argument(
+        '--distro',
+        help='Linux distribution to run tests on',
+        choices=linux.DISTROS,
+        default='debian9',
+    )
+    sp.add_argument(
+        '--filesystem',
+        help='Filesystem type to use',
+        choices={'btrfs', 'default', 'ext3', 'ext4', 'jfs', 'tmpfs', 'xfs'},
+        default='default',
+    )
+    sp.add_argument(
+        '--instance-type',
+        help='EC2 instance type to use',
+        default='c5.9xlarge',
+    )
+    sp.add_argument(
+        '--python-version',
+        help='Python version to use',
+        choices={'system2', 'system3', '2.7', '3.5', '3.6', '3.7', '3.8',
+                 'pypy', 'pypy3.5', 'pypy3.6'},
+        default='system2',
+    )
+    sp.add_argument(
+        'test_flags',
+        help='Extra command line flags to pass to run-tests.py',
+        nargs='*',
+    )
+    sp.set_defaults(func=run_tests_linux)
+
+    sp = subparsers.add_parser(
         'run-tests-windows',
         help='Run tests on Windows',
     )