%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
-module(efile_SUITE).
-export([all/0, suite/0]).
-export([iter_max_files/1, async_dist/1]).
-export([do_iter_max_files/2, do_async_dist/1]).
-include_lib("common_test/include/ct.hrl").
suite() -> [{ct_hooks,[ts_install_cth]}].
all() ->
[iter_max_files, async_dist].
do_async_dist(Dir) ->
X = 100,
AT = erlang:system_info(thread_pool_size),
Keys = file_keys(Dir,AT*X,[],[]),
Tab = ets:new(x,[ordered_set]),
[ ets:insert(Tab,{N,0}) || N <- lists:seq(0,AT-1) ],
[ ets:update_counter(Tab,(N rem AT),1) || N <- Keys ],
Res = [ V || {_,V} <- ets:tab2list(Tab) ],
ets:delete(Tab),
{Res, sdev(Res)/X}.
sdev(List) ->
Len = length(List),
Mean = lists:sum(List)/Len,
math:sqrt(lists:sum([ (X - Mean) * (X - Mean) || X <- List ]) / Len).
file_keys(_,0,FdList,FnList) ->
[ file:close(FD) || FD <- FdList ],
[ file:delete(FN) || FN <- FnList ],
[];
file_keys(Dir,Num,FdList,FnList) ->
Name = "dummy"++integer_to_list(Num),
FN = filename:join([Dir,Name]),
case file:open(FN,[write,raw]) of
{ok,FD} ->
{file_descriptor,prim_file,{Port,_}} = FD,
<<X:32/integer-big>> =
iolist_to_binary(erlang:port_control(Port,$K,[])),
[X | file_keys(Dir,Num-1,[FD|FdList],[FN|FnList])];
{error,_} ->
% Try freeing up FD's if there are any
case FdList of
[] ->
exit({cannot_open_file,FN});
_ ->
[ file:close(FD) || FD <- FdList ],
[ file:delete(F) || F <- FnList ],
file_keys(Dir,Num,[],[])
end
end.
%% Check that the distribution of files over async threads is fair
async_dist(Config) when is_list(Config) ->
DataDir = proplists:get_value(data_dir,Config),
Dir = filename:dirname(code:which(?MODULE)),
AsyncSizes = [7,10,100,255,256,64,63,65],
Max = 0.5,
lists:foreach(fun(Size) ->
{ok,Node} =
test_server:start_node
(test_iter_max_files,slave,
[{args,
"+A "++integer_to_list(Size)++
" -pa " ++ Dir}]),
{Distr,SD} = rpc:call(Node,?MODULE,do_async_dist,
[DataDir]),
test_server:stop_node(Node),
if
SD > Max ->
io:format("Bad async queue distribution for "
"~p async threads:~n"
" Standard deviation is ~p~n"
" Key distribution:~n ~lp~n",
[Size,SD,Distr]),
exit({bad_async_dist,Size,SD,Distr});
true ->
io:format("OK async queue distribution for "
"~p async threads:~n"
" Standard deviation is ~p~n"
" Key distribution:~n ~lp~n",
[Size,SD,Distr]),
ok
end
end, AsyncSizes),
ok.
%%
%% Open as many files as possible. Do this several times and check
%% that we get the same number of files every time.
%%
iter_max_files(Config) when is_list(Config) ->
DataDir = proplists:get_value(data_dir,Config),
TestFile = filename:join(DataDir, "existing_file"),
N = 10,
%% Run on a different node in order to set the max ports
Dir = filename:dirname(code:which(?MODULE)),
{ok,Node} = test_server:start_node(test_iter_max_files,slave,
[{args,"+Q 1524 -pa " ++ Dir}]),
L = rpc:call(Node,?MODULE,do_iter_max_files,[N, TestFile]),
test_server:stop_node(Node),
io:format("Number of files opened in each test:~n~w\n", [L]),
all_equal(L),
Head = hd(L),
if Head >= 2 -> ok;
true -> ct:fail(too_few_files)
end,
{comment, "Max files: " ++ integer_to_list(hd(L))}.
do_iter_max_files(N, Name) when N > 0 ->
[max_files(Name)| do_iter_max_files(N-1, Name)];
do_iter_max_files(_, _) ->
[].
all_equal([E, E| T]) ->
all_equal([E| T]);
all_equal([_]) ->
ok;
all_equal([]) ->
ok.
max_files(Name) ->
Fds = open_files(Name),
N = length(Fds),
close_files(Fds),
N.
close_files([Fd| Fds]) ->
file:close(Fd),
close_files(Fds);
close_files([]) ->
ok.
open_files(Name) ->
case file:open(Name, [read,raw]) of
{ok, Fd} ->
[Fd| open_files(Name)];
{error, _Reason} ->
% io:format("Error reason: ~p", [_Reason]),
[]
end.
