Improve compression eunit test suite

Use the simpler `?TDEF_FE` macro and fix timeout usage bug. EUnit timeout is in
seconds, while test_util:wait/2 takes milliseconds. This was revealed due a
slow disk IO speed on the new s390x worker.

To reduce flakiness and to ensure db / view size before compaction is greater
than the size after compaction, even with `none` compression option, make db
update batches smaller and use more frequent index commits.

Issue: #4521

src/couch/test/eunit/couchdb_file_compression_tests.erl

@@ -18,9 +18,38 @@
 -define(DDOC_ID, <<"_design/test">>).
 -define(DOCS_COUNT, 1000).
 -define(TIMEOUT, 60).
+% Smaller doc batches will generate more garbage
+-define(BATCH_SIZE, 100).
 
 setup_all() ->
     Ctx = test_util:start_couch(),
+    config:set("query_server_config", "commit_freq", "0", false),
+    config:set("couchdb", "file_compression", "none", false),
+    Ctx.
+
+teardown_all(Ctx) ->
+    config:delete("couchdb", "file_compression", false),
+    config:delete("query_server_config", "commit_freq", false),
+    test_util:stop_couch(Ctx).
+
+couch_file_compression_test_() ->
+    {
+        "CouchDB file compression tests",
+        {
+            setup,
+            fun setup_all/0,
+            fun teardown_all/1,
+            {foreach, fun setup/0, fun teardown/1, [
+                ?TDEF_FE(should_use_none, ?TIMEOUT),
+                ?TDEF_FE(should_use_deflate_1, ?TIMEOUT),
+                ?TDEF_FE(should_use_deflate_9, ?TIMEOUT),
+                ?TDEF_FE(should_use_snappy, ?TIMEOUT),
+                ?TDEF_FE(should_compare_compression_methods, ?TIMEOUT)
+            ]}
+        }
+    }.
+
+setup() ->
     config:set("couchdb", "file_compression", "none", false),
     DbName = ?tempdb(),
     {ok, Db} = couch_db:create(DbName, [?ADMIN_CTX]),
@@ -40,58 +69,34 @@ setup_all() ->
     ),
     {ok, _} = couch_db:update_doc(Db, DDoc, []),
     ok = couch_db:close(Db),
-    {Ctx, DbName}.
+    ok = refresh_index(DbName),
+    DbName.
 
-teardown_all({Ctx, DbName}) ->
-    ok = couch_server:delete(DbName, [?ADMIN_CTX]),
-    test_util:stop_couch(Ctx).
+teardown(DbName) ->
+    config:delete("couchdb", "file_compression", false),
+    couch_server:delete(DbName, [?ADMIN_CTX]).
 
-couch_file_compression_test_() ->
-    {
-        "CouchDB file compression tests",
-        {
-            setup,
-            fun setup_all/0,
-            fun teardown_all/1,
-            {with, [
-                fun should_use_none/1,
-                fun should_use_deflate_1/1,
-                fun should_use_deflate_9/1,
-                fun should_use_snappy/1,
-                fun should_compare_compression_methods/1
-            ]}
-        }
-    }.
+should_use_none(DbName) ->
+    config:set("couchdb", "file_compression", "none", false),
+    compact_db(DbName),
+    compact_view(DbName).
 
-should_use_none({_, DbName}) -> run_test(DbName, "none").
-should_use_deflate_1({_, DbName}) -> run_test(DbName, "deflate_1").
-should_use_deflate_9({_, DbName}) -> run_test(DbName, "deflate_9").
-should_use_snappy({_, DbName}) -> run_test(DbName, "snappy").
-
-should_compare_compression_methods({_, DbName}) ->
-    TestDb = setup_db(DbName),
-    Name = "none > snappy > deflate_1 > deflate_9",
-    try
-        {Name, {timeout, ?TIMEOUT, ?_test(compare_methods(TestDb))}}
-    after
-        couch_server:delete(TestDb, [?ADMIN_CTX])
-    end.
+should_use_deflate_1(DbName) ->
+    config:set("couchdb", "file_compression", "deflate_1", false),
+    compact_db(DbName),
+    compact_view(DbName).
 
-run_test(DbName, Comp) ->
-    config:set("couchdb", "file_compression", Comp, false),
-    Timeout = 5 + ?TIMEOUT,
-    TestDb = setup_db(DbName),
-    Tests = [
-        {"compact database", {timeout, Timeout, ?_test(compact_db(DbName))}},
-        {"compact view", {timeout, Timeout, ?_test(compact_view(DbName))}}
-    ],
-    try
-        {"Use compression: " ++ Comp, Tests}
-    after
-        ok = couch_server:delete(TestDb, [?ADMIN_CTX])
-    end.
+should_use_deflate_9(DbName) ->
+    config:set("couchdb", "file_compression", "deflate_9", false),
+    compact_db(DbName),
+    compact_view(DbName).
+
+should_use_snappy(DbName) ->
+    config:set("couchdb", "file_compression", "deflate_9", false),
+    compact_db(DbName),
+    compact_view(DbName).
 
-compare_methods(DbName) ->
+should_compare_compression_methods(DbName) ->
     config:set("couchdb", "file_compression", "none", false),
     ExternalSizePreCompact = db_external_size(DbName),
     compact_db(DbName),
@@ -149,21 +154,10 @@ populate_db(Db, NumDocs) ->
                 ]}
             )
         end,
-        lists:seq(1, 500)
+        lists:seq(1, ?BATCH_SIZE)
     ),
     {ok, _} = couch_db:update_docs(Db, Docs, []),
-    populate_db(Db, NumDocs - 500).
-
-setup_db(SrcDbName) ->
-    TgtDbName = ?tempdb(),
-    TgtDbFileName = binary_to_list(TgtDbName) ++ ".couch",
-    couch_util:with_db(SrcDbName, fun(Db) ->
-        OldPath = couch_db:get_filepath(Db),
-        NewPath = filename:join(filename:dirname(OldPath), TgtDbFileName),
-        {ok, _} = file:copy(OldPath, NewPath)
-    end),
-    refresh_index(TgtDbName),
-    TgtDbName.
+    populate_db(Db, NumDocs - ?BATCH_SIZE).
 
 refresh_index(DbName) ->
     {ok, Db} = couch_db:open_int(DbName, []),
@@ -226,7 +220,7 @@ wait_compaction(DbName, Kind, Line) ->
             false -> ok
         end
     end,
-    case test_util:wait(WaitFun, ?TIMEOUT) of
+    case test_util:wait(WaitFun, ?TIMEOUT * 1000) of
         timeout ->
             erlang:error(
                 {assertion_failed, [