test: add tests for zfs_arc_max calculations

Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>

Makefile

@@ -45,6 +45,7 @@ $(BUILDDIR):
 	  proxmox-tui-installer/ \
 	  proxmox-installer-common/ \
 	  spice-vdagent.sh \
+	  test/ \
 	  unconfigured.sh \
 	  xinitrc \
 	  $@.tmp
@@ -76,7 +77,9 @@ $(DSC): $(BUILDDIR)
 sbuild: $(DSC)
 	sbuild $(DSC)
 
+.PHONY: test
 test:
+	$(MAKE) -C test check
 	$(CARGO) test --workspace $(CARGO_BUILD_ARGS)
 
 DESTDIR=

debian/control

@@ -11,6 +11,7 @@ Build-Depends: cargo:native,
                librust-regex-1+default-dev (>= 1.7~~),
                librust-serde-1+default-dev,
                librust-serde-json-1+default-dev,
+               libtest-mockmodule-perl,
                perl,
                rustc:native,
 Standards-Version: 4.5.1

test/Makefile

@@ -0,0 +1,10 @@
+all:
+
+export PERLLIB=..
+
+.PHONY: check
+check: test-zfs-arc-max
+
+.PHONY: test-zfs-arc-max
+test-zfs-arc-max:
+	./zfs-arc-max.pl

test/zfs-arc-max.pl

@@ -0,0 +1,81 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+use Test::More;
+use Test::MockModule qw(strict);
+
+my $proxmox_install_runenv = Test::MockModule->new('Proxmox::Install::RunEnv');
+my $proxmox_install_isoenv = Test::MockModule->new('Proxmox::Install::ISOEnv');
+
+sub mock_product {
+    my ($product) = @_;
+
+    $proxmox_install_isoenv->redefine(
+	get => sub {
+	    my ($k) = @_;
+	    return $product if $k eq 'product';
+	    die "iso environment key $k not mocked!\n";
+	},
+    );
+}
+
+my %default_tests = (
+    16 => 64, # at least 64 MiB
+    1024 => 102,
+    4 * 1024 => 410,
+    8 * 1024 => 819,
+    150 * 1024 => 15360,
+    160 * 1024 => 16384,
+    1024 * 1024 => 16384, # maximum of 16 GiB
+);
+
+while (my ($total_mem, $expected) = each %default_tests) {
+    $proxmox_install_runenv->redefine(
+	get => sub {
+	    my ($k) = @_;
+	    return $total_mem if $k eq 'total_memory';
+	    die "runtime environment key $k not mocked!\n";
+	},
+    );
+
+    mock_product('pve');
+    is(Proxmox::Install::RunEnv::default_zfs_arc_max(), $expected,
+	"$expected MiB should be zfs_arc_max for PVE with $total_mem MiB system memory");
+
+    mock_product('pbs');
+    is(Proxmox::Install::RunEnv::default_zfs_arc_max(), 0,
+	"zfs_arc_max should default to `0` for PBS with $total_mem MiB system memory");
+
+    mock_product('pmg');
+    is(Proxmox::Install::RunEnv::default_zfs_arc_max(), 0,
+	"zfs_arc_max should default to `0` for PMG with $total_mem MiB system memory");
+}
+
+my @clamp_tests = (
+    # input, total system memory, expected
+    [ 0, 4 * 1024, 0 ],
+    [ 16, 4 * 1024, 64 ],
+    [ 4 * 1024, 4 * 1024, 4 * 1024 ],
+    [ 4 * 1024, 6 * 1024, 4 * 1024 ],
+    [ 8 * 1024, 4 * 1024, 4 * 1024 ],
+);
+
+mock_product('pve');
+foreach (@clamp_tests) {
+    my ($input, $total_mem, $expected) = @$_;
+
+    $proxmox_install_runenv->redefine(
+	get => sub {
+	    my ($k) = @_;
+	    return $total_mem if $k eq 'total_memory';
+	    die "runtime environment key $k not mocked!\n";
+	},
+    );
+
+    is(Proxmox::Install::RunEnv::clamp_zfs_arc_max($input), $expected,
+	"$input MiB zfs_arc_max should be clamped to $expected MiB with $total_mem MiB system memory");
+}
+
+done_testing();