Avoid scanning huge freelists for large enough free blocks.

tests/standalone/standalone.status

 # Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # WARNING:
 # Tests using the multitest feature where failure is expected should *also* be
 # listed in tests/lib/analyzer/analyze_tests.status without the "standalone"
 # prefix.
 
 io/raw_socket_test: Pass, RuntimeError # Issue 28288
@@ skipping 130 matching lines @@
 regress_25335_test: Skip # Int64List not supported.
 deferred_transitive_import_error_test: Skip # Contains intentional errors.
 dart_developer_env_test: SkipByDesign # Unsupported by dart2js
 dart_developer_disabled_env_test: SkipByDesign # Unsupported by dart2js
 
 [ $runtime == vm && ($arch == arm || $arch == arm64) ]
 io/file_stream_test: Skip # Issue 26109
 io/file_typed_data_test: Skip # Issue 26109
 io/file_input_stream_test: Skip # Issue 26109
 
+[ $runtime != vm || ($arch == arm || $arch == arm64 || $arch == mips) ]
+fragmentation_test: Skip # VM test uses too much memory for small systems.
+
 [ $compiler == dart2js && $jscl ]
 assert_test: RuntimeError, OK # Assumes unspecified fields on the AssertionError.
 deoptimization_test: RuntimeError, OK # Requires bigint.
 out_of_memory_test: RuntimeError, OK # d8 handles much larger arrays than Dart VM.
 io/arguments_test: CompileTimeError, OK # Cannot pass arguments to d8.
 
 [ $compiler == dart2js && $runtime == none ]
 io/arguments_test: Fail # DartOptions not supported by dart2js, and issue 14200.
 medium_integer_test: Pass # The test only fails at runtime, not at compilation.
 oom_error_stacktrace_test: Pass # The test only fails at runtime.
@@ skipping 377 matching lines @@
 package/scenarios/packages_dir_only/packages_dir_only_test: Fail # Unable to parse package files Flutter Issue 9115
 package/scenarios/both_dir_and_file/prefers_packages_file_test: Fail # Unable to parse package files Flutter Issue 9115
 package/package_test: Fail # Unable to parse package files Flutter Issue 9115
 #unboxed_int_converter_test: Fail # Unable to parse package files Flutter Issue 9115
 io/process_run_output_test: Fail # Unable to parse package files Flutter Issue 9115
 
 io/test_harness_analyzer_test: CompileTimeError # Uses mirrors
 io/skipping_dart2js_compilations_test: CompileTimeError # Uses mirrors
 io/test_runner_test: CompileTimeError # Uses mirrors