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Mas d34 leveled.i459 partialmerge (#460)

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* Add test to replicate issue 459

Nothing actually crashes due to the issue - but looking at the logs there is the polarised stats associated with the issue.  When  merging into L3, you would normally expect to merge into 4 files - but actually we see FileCounter occasionally spiking.

* Add partial merge support

There is a `max_mergebelow` size which can be a positive integer, or infinity.  It defaults to 32.

If a merge from Level N covers less than `max_mergebelow` files in level N + 1 - the merge will proceesd as before.  If it has >= `max_mergebelow`, the merge will be curtailed when `max_mergebelow div 2` files have been created at that level.  The remainder for Level N will then be written, as well as for Level N + 1 up to the next whole file that has no yet been touched by the merge.

The backlog that prompted the merge will still exist - as the files in Level N have not been changed.  However, it is likely the next file picked will not be the same one, and will in probability have a lower number of files to merge (as the average is =< 8).

This will stop progress from being halted by long merge jobs, as they will exit out in a safe way after partial completion.  In the case where the majority of files covered  do not require a merge, then those files will be skipped the next time the remainder file is picked up for merge at Level N
This commit is contained in:
Martin Sumner 2024-11-30 13:16:13 +00:00 • committed by GitHub
parent c642575caa
commit 69e8b29d1f
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8 changed files with 360 additions and 66 deletions
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4
include/leveled.hrl
View file

@ -33,6 +33,7 @@
%%% Non-configurable startup defaults
%%%============================================================================
-define(MAX_SSTSLOTS, 256).
-define(MAX_MERGEBELOW, 24).
-define(LOADING_PAUSE, 1000).
-define(LOADING_BATCH, 1000).
-define(CACHE_SIZE_JITTER, 25).
@ -109,7 +110,8 @@
press_level = ?COMPRESSION_LEVEL :: non_neg_integer(),
log_options = leveled_log:get_opts()
:: leveled_log:log_options(),
max_sstslots = ?MAX_SSTSLOTS :: pos_integer(),
max_sstslots = ?MAX_SSTSLOTS :: pos_integer()|infinity,
max_mergebelow = ?MAX_MERGEBELOW :: pos_integer()|infinity,
pagecache_level = ?SST_PAGECACHELEVEL_NOLOOKUP
:: pos_integer(),
monitor = {no_monitor, 0}

8
rebar.config
View file

@ -13,11 +13,7 @@
{eunit_opts, [verbose]}.
{project_plugins, [
{eqwalizer_rebar3,
{git_subdir,
"https://github.com/whatsapp/eqwalizer.git",
{branch, "main"},
"eqwalizer_rebar3"}}
{eqwalizer_rebar3, {git_subdir, "https://github.com/OpenRiak/eqwalizer.git", {branch, "openriak-3.4"}, "eqwalizer_rebar3"}}
]}.
{profiles,
@ -37,7 +33,7 @@
{deps, [
{lz4, ".*", {git, "https://github.com/nhs-riak/erlang-lz4", {branch, "nhse-develop-3.4"}}},
{zstd, ".*", {git, "https://github.com/nhs-riak/zstd-erlang", {branch, "nhse-develop"}}},
{eqwalizer_support, {git_subdir, "https://github.com/whatsapp/eqwalizer.git", {branch, "main"}, "eqwalizer_support"}}
{eqwalizer_support, {git_subdir, "https://github.com/OpenRiak/eqwalizer.git", {branch, "openriak-3.4"}, "eqwalizer_support"}}
]}.
{ct_opts, [{dir, ["test/end_to_end"]}]}.

11
src/leveled_bookie.erl
View file

@ -114,6 +114,7 @@
{max_journalsize, 1000000000},
{max_journalobjectcount, 200000},
{max_sstslots, 256},
{max_mergebelow, 24},
{sync_strategy, ?DEFAULT_SYNC_STRATEGY},
{head_only, false},
{waste_retention_period, undefined},
@ -201,6 +202,12 @@
% The maximum number of slots in a SST file. All testing is done
% at a size of 256 (except for Quickcheck tests}, altering this
% value is not recommended
{max_mergeblow, pos_integer()|infinity} |
% The maximum number of files for a single file to be merged into
% within the ledger. If less than this, the merge will continue
% without a maximum. If this or more overlapping below, only up
% to max_mergebelow div 2 additions should be created (the merge
% should be partial)
{sync_strategy, sync_mode()} |
% Should be sync if it is necessary to flush to disk after every
% write, or none if not (allow the OS to schecdule). This has a
@ -293,7 +300,7 @@
% To which level of the ledger should the ledger contents be
% pre-loaded into the pagecache (using fadvise on creation and
% startup)
{compression_method, native|lz4|zstd|none} |
{compression_method, native|lz4|zstd|none} |
% Compression method and point allow Leveled to be switched from
% using bif based compression (zlib) to using nif based compression
% (lz4 or zstd).
@ -1871,6 +1878,7 @@ set_options(Opts, Monitor) ->
CompressionLevel = proplists:get_value(compression_level, Opts),
MaxSSTSlots = proplists:get_value(max_sstslots, Opts),
MaxMergeBelow = proplists:get_value(max_mergebelow, Opts),
ScoreOneIn = proplists:get_value(journalcompaction_scoreonein, Opts),
@ -1904,6 +1912,7 @@ set_options(Opts, Monitor) ->
press_level = CompressionLevel,
log_options = leveled_log:get_opts(),
max_sstslots = MaxSSTSlots,
max_mergebelow = MaxMergeBelow,
monitor = Monitor},
monitor = Monitor}
}.

4
src/leveled_log.erl
View file

@ -165,7 +165,7 @@
pc010 =>
{info, <<"Merge to be commenced for FileToMerge=~s with MSN=~w">>},
pc011 =>
{info, <<"Merge completed with MSN=~w to Level=~w and FileCounter=~w">>},
{info, <<"Merge completed with MSN=~w to Level=~w and FileCounter=~w merge_type=~w">>},
pc012 =>
{debug, <<"File to be created as part of MSN=~w Filename=~s IsBasement=~w">>},
pc013 =>
@ -190,6 +190,8 @@
{info, <<"Grooming compaction picked file with tomb_count=~w">>},
pc025 =>
{info, <<"At level=~w file_count=~w average words for heap_block_size=~w heap_size=~w recent_size=~w bin_vheap_size=~w">>},
pc026 =>
{info, <<"Performing potential partial to level=~w merge as FileCounter=~w restricting to MaxAdditions=~w">>},
pm002 =>
{info, <<"Completed dump of L0 cache to list of l0cache_size=~w">>},
sst03 =>

211
src/leveled_pclerk.erl
View file

@ -269,7 +269,6 @@ notify_deletions([Head|Tail], Penciller) ->
%% to be merged into multiple SSTs at a lower level.
%%
%% SrcLevel is the level of the src sst file, the sink should be srcLevel + 1
perform_merge(Manifest, Src, SinkList, SrcLevel, RootPath, NewSQN, OptsSST) ->
leveled_log:log(pc010, [leveled_pmanifest:entry_filename(Src), NewSQN]),
SrcList = [{next, Src, all}],
@ -279,72 +278,188 @@ perform_merge(Manifest, Src, SinkList, SrcLevel, RootPath, NewSQN, OptsSST) ->
),
SinkLevel = SrcLevel + 1,
SinkBasement = leveled_pmanifest:is_basement(Manifest, SinkLevel),
Additions =
MaxMergeBelow = OptsSST#sst_options.max_mergebelow,
MergeLimit = merge_limit(SrcLevel, length(SinkList), MaxMergeBelow),
{L2Additions, L1Additions, L2FileRemainder} =
do_merge(
SrcList, SinkList,
SinkLevel, SinkBasement,
RootPath, NewSQN, MaxSQN,
OptsSST,
[]
[],
MergeLimit
),
RevertPointerFun = fun({next, ME, _SK}) -> ME end,
SinkManifestRemovals =
lists:subtract(
lists:map(RevertPointerFun, SinkList),
lists:map(RevertPointerFun, L2FileRemainder)
),
RevertPointerFun =
fun({next, ME, _SK}) ->
ME
end,
SinkManifestList = lists:map(RevertPointerFun, SinkList),
Man0 =
leveled_pmanifest:replace_manifest_entry(
Manifest,
NewSQN,
SinkLevel,
SinkManifestList,
Additions
SinkManifestRemovals,
L2Additions
),
Man2 =
leveled_pmanifest:remove_manifest_entry(
Man0,
NewSQN,
SrcLevel,
Src
),
{Man2, [Src|SinkManifestList]}.
Man1 =
case L1Additions of
[] ->
leveled_pmanifest:remove_manifest_entry(
Man0,
NewSQN,
SrcLevel,
Src
);
PartialFiles ->
leveled_pmanifest:replace_manifest_entry(
Man0,
NewSQN,
SrcLevel,
[Src],
PartialFiles
)
end,
{Man1, [Src|SinkManifestRemovals]}.
do_merge([], [], SinkLevel, _SinkB, _RP, NewSQN, _MaxSQN, _Opts, Additions) ->
leveled_log:log(pc011, [NewSQN, SinkLevel, length(Additions)]),
lists:reverse(Additions);
do_merge(KL1, KL2, SinkLevel, SinkB, RP, NewSQN, MaxSQN, OptsSST, Additions) ->
-spec merge_limit(
non_neg_integer(), non_neg_integer(), pos_integer()|infinity)
-> pos_integer()|infinity.
merge_limit(SrcLevel, SinkListLength, MMB) when SrcLevel =< 1; SinkListLength < MMB ->
infinity;
merge_limit(SrcLevel, SinkListLength, MMB) when is_integer(MMB) ->
AdditionsLimit = max(1, MMB div 2),
leveled_log:log(pc026, [SrcLevel + 1, SinkListLength, AdditionsLimit]),
AdditionsLimit.
-type merge_maybe_expanded_pointer() ::
leveled_codec:ledger_kv()|
leveled_sst:slot_pointer()|
leveled_sst:sst_pointer().
% Different to leveled_sst:maybe_expanded_pointer/0
% No sst_closed_pointer()
-spec do_merge(
list(merge_maybe_expanded_pointer()),
list(merge_maybe_expanded_pointer()),
leveled_pmanifest:lsm_level(),
boolean(),
string(),
pos_integer(),
pos_integer(),
leveled_sst:sst_options(),
list(leveled_pmanifest:manifest_entry()),
pos_integer()|infinity) ->
{
list(leveled_pmanifest:manifest_entry()),
list(leveled_pmanifest:manifest_entry()),
list(leveled_sst:sst_pointer())
}.
do_merge(
[], [], SinkLevel, _SinkB, _RP, NewSQN, _MaxSQN, _Opts, Additions, _Max) ->
leveled_log:log(pc011, [NewSQN, SinkLevel, length(Additions), full]),
{lists:reverse(Additions), [], []};
do_merge(
KL1, KL2, SinkLevel, SinkB, RP, NewSQN, MaxSQN, OptsSST, Additions, Max)
when length(Additions) >= Max ->
leveled_log:log(pc011, [NewSQN, SinkLevel, length(Additions), partial]),
FNSrc =
leveled_penciller:sst_filename(
NewSQN, SinkLevel - 1, 1
),
FNSnk =
leveled_penciller:sst_filename(
NewSQN, SinkLevel, length(Additions) + 1
),
{ExpandedKL1, []} = split_unexpanded_files(KL1),
{ExpandedKL2, L2FilePointersRem} = split_unexpanded_files(KL2),
TS1 = os:timestamp(),
InfOpts = OptsSST#sst_options{max_sstslots = infinity},
% Need to be careful to make sure all the remainder goes in one file,
% could be situations whereby the max_sstslots has been changed between
% restarts - and so there is too much data for one file in the
% remainder ... but don't want to loop round and consider more complex
% scenarios here.
NewMergeKL1 =
leveled_sst:sst_newmerge(
RP, FNSrc,ExpandedKL1, [], false, SinkLevel - 1, MaxSQN, InfOpts
),
TS2 = os:timestamp(),
NewMergeKL2 =
leveled_sst:sst_newmerge(
RP, FNSnk, [], ExpandedKL2, SinkB, SinkLevel, MaxSQN, InfOpts
),
{KL1Additions, [], []} = add_entry(NewMergeKL1, FNSrc, TS1, []),
{KL2Additions, [], []} = add_entry(NewMergeKL2, FNSnk, TS2, Additions),
{lists:reverse(KL2Additions), KL1Additions, L2FilePointersRem};
do_merge(
KL1, KL2, SinkLevel, SinkB, RP, NewSQN, MaxSQN, OptsSST, Additions, Max) ->
FileName =
leveled_penciller:sst_filename(
NewSQN, SinkLevel, length(Additions)
),
leveled_log:log(pc012, [NewSQN, FileName, SinkB]),
TS1 = os:timestamp(),
case leveled_sst:sst_newmerge(RP, FileName,
KL1, KL2, SinkB, SinkLevel, MaxSQN,
OptsSST) of
empty ->
leveled_log:log(pc013, [FileName]),
do_merge(
[], [],
SinkLevel, SinkB,
RP, NewSQN, MaxSQN,
OptsSST,
Additions
);
{ok, Pid, Reply, Bloom} ->
{{KL1Rem, KL2Rem}, SmallestKey, HighestKey} = Reply,
Entry =
leveled_pmanifest:new_entry(
SmallestKey, HighestKey, Pid, FileName, Bloom),
leveled_log:log_timer(pc015, [], TS1),
do_merge(
KL1Rem, KL2Rem,
SinkLevel, SinkB,
RP, NewSQN, MaxSQN,
OptsSST,
[Entry|Additions]
)
end.
NewMerge =
leveled_sst:sst_newmerge(
RP, FileName, KL1, KL2, SinkB, SinkLevel, MaxSQN, OptsSST),
{UpdAdditions, KL1Rem, KL2Rem} =
add_entry(NewMerge, FileName, TS1, Additions),
do_merge(
KL1Rem,
KL2Rem,
SinkLevel,
SinkB,
RP,
NewSQN,
MaxSQN,
OptsSST,
UpdAdditions,
Max
).
add_entry(empty, FileName, _TS1, Additions) ->
leveled_log:log(pc013, [FileName]),
{[], [], Additions};
add_entry({ok, Pid, Reply, Bloom}, FileName, TS1, Additions) ->
{{KL1Rem, KL2Rem}, SmallestKey, HighestKey} = Reply,
Entry =
leveled_pmanifest:new_entry(
SmallestKey, HighestKey, Pid, FileName, Bloom),
leveled_log:log_timer(pc015, [], TS1),
{[Entry|Additions], KL1Rem, KL2Rem}.
-spec split_unexpanded_files(
list(merge_maybe_expanded_pointer())) ->
{
list(leveled_codec:ledger_kv()|leveled_sst:slot_pointer()),
list(leveled_sst:sst_pointer())
}.
split_unexpanded_files(Pointers) ->
split_unexpanded_files(Pointers, [], []).
-spec split_unexpanded_files(
list(merge_maybe_expanded_pointer()),
list(leveled_codec:ledger_kv()|leveled_sst:slot_pointer()),
list(leveled_sst:sst_pointer())) ->
{
list(leveled_codec:ledger_kv()|leveled_sst:slot_pointer()),
list(leveled_sst:sst_pointer())
}.
split_unexpanded_files([], MaybeExpanded, FilePointers) ->
{lists:reverse(MaybeExpanded), lists:reverse(FilePointers)};
split_unexpanded_files([{next, P, SK}|Rest], MaybeExpanded, FilePointers) ->
split_unexpanded_files(Rest, MaybeExpanded, [{next, P, SK}|FilePointers]);
split_unexpanded_files([{LK, LV}|Rest], MaybeExpanded, []) ->
% Should never see this, once a FilePointer has been seen
split_unexpanded_files(Rest, [{LK, LV}|MaybeExpanded], []);
split_unexpanded_files([{pointer, P, SIV, SK, EK}|Rest], MaybeExpanded, []) ->
% Should never see this, once a FilePointer has been seen
split_unexpanded_files(
Rest, [{pointer, P, SIV, SK, EK}|MaybeExpanded], []
).
-spec grooming_scorer(
list(leveled_pmanifest:manifest_entry()))

23
src/leveled_sst.erl
View file

@ -248,7 +248,18 @@
-type build_timings() :: no_timing|#build_timings{}.
-export_type([expandable_pointer/0, press_method/0, segment_check_fun/0]).
-export_type(
[
expandable_pointer/0,
maybe_expanded_pointer/0,
sst_closed_pointer/0,
sst_pointer/0,
slot_pointer/0,
press_method/0,
segment_check_fun/0,
sst_options/0
]
).
%%%============================================================================
%%% API
@ -312,8 +323,8 @@ sst_new(RootPath, Filename, Level, KVList, MaxSQN, OptsSST, IndexModDate) ->
end.
-spec sst_newmerge(string(), string(),
list(leveled_codec:ledger_kv()|sst_pointer()),
list(leveled_codec:ledger_kv()|sst_pointer()),
list(maybe_expanded_pointer()),
list(maybe_expanded_pointer()),
boolean(), leveled_pmanifest:lsm_level(),
integer(), sst_options())
-> empty|{ok, pid(),
@ -1529,7 +1540,9 @@ compress_level(_Level, _LevelToCompress, PressMethod) ->
PressMethod.
-spec maxslots_level(
leveled_pmanifest:lsm_level(), pos_integer()) -> pos_integer().
leveled_pmanifest:lsm_level(), pos_integer()|infinity) -> pos_integer()|infinity.
maxslots_level(_Level, infinity) ->
infinity;
maxslots_level(Level, MaxSlotCount) when Level < ?DOUBLESIZE_LEVEL ->
MaxSlotCount;
maxslots_level(_Level, MaxSlotCount) ->
@ -3020,7 +3033,7 @@ merge_lists(
list(binary_slot()),
leveled_codec:ledger_key()|null,
non_neg_integer(),
non_neg_integer(),
pos_integer()|infinity,
press_method(),
boolean(),
non_neg_integer(),

159
test/end_to_end/riak_SUITE.erl
View file

@ -2,8 +2,9 @@
-include("leveled.hrl").
-export([all/0, init_per_suite/1, end_per_suite/1]).
-export([all/0, init_per_suite/1, end_per_suite/1, suite/0]).
-export([
test_large_lsm_merge/1,
basic_riak/1,
fetchclocks_modifiedbetween/1,
crossbucket_aae/1,
@ -14,6 +15,8 @@
summarisable_sstindex/1
]).
suite() -> [{timetrap, {hours, 2}}].
all() -> [
basic_riak,
fetchclocks_modifiedbetween,
@ -22,7 +25,8 @@ all() -> [
dollar_bucket_index,
dollar_key_index,
bigobject_memorycheck,
summarisable_sstindex
summarisable_sstindex,
test_large_lsm_merge
].
-define(MAGIC, 53). % riak_kv -> riak_object
@ -34,11 +38,160 @@ init_per_suite(Config) ->
end_per_suite(Config) ->
testutil:end_per_suite(Config).
test_large_lsm_merge(_Config) ->
lsm_merge_tester(24).
lsm_merge_tester(LoopsPerBucket) ->
RootPath = testutil:reset_filestructure("lsmMerge"),
PutsPerLoop = 32000,
SampleOneIn = 100,
StartOpts1 =
[
{root_path, RootPath},
{max_pencillercachesize, 16000},
{max_sstslots, 96},
% Make SST files smaller, to accelerate merges
{max_mergebelow, 24},
{sync_strategy, testutil:sync_strategy()},
{log_level, warn},
{compression_method, zstd},
{
forced_logs,
[
b0015, b0016, b0017, b0018, p0032, sst12,
pc008, pc010, pc011, pc026,
p0018, p0024
]
}
],
{ok, Bookie1} = leveled_bookie:book_start(StartOpts1),
LoadBucketFun =
fun(Book, Bucket, Loops) ->
V = testutil:get_compressiblevalue(),
lists:foreach(
fun(_I) ->
{_, V} =
testutil:put_indexed_objects(
Book,
Bucket,
PutsPerLoop,
V
)
end,
lists:seq(1, Loops)
),
V
end,
V1 = LoadBucketFun(Bookie1, <<"B1">>, LoopsPerBucket),
io:format("Completed load of ~s~n", [<<"B1">>]),
V2 = LoadBucketFun(Bookie1, <<"B2">>, LoopsPerBucket),
io:format("Completed load of ~s~n", [<<"B2">>]),
ValueMap = #{<<"B1">> => V1, <<"B2">> => V2},
CheckBucketFun =
fun(Book) ->
BookHeadFoldFun =
fun(B, K, _Hd, {SampleKeys, CountAcc}) ->
UpdCntAcc =
maps:update_with(B, fun(C) -> C + 1 end, 1, CountAcc),
case rand:uniform(SampleOneIn) of
R when R == 1 ->
{[{B, K}|SampleKeys], UpdCntAcc};
_ ->
{SampleKeys, UpdCntAcc}
end
end,
{async, HeadFolder} =
leveled_bookie:book_headfold(
Book,
?RIAK_TAG,
{BookHeadFoldFun, {[], maps:new()}},
true,
false,
false
),
{Time, R} = timer:tc(HeadFolder),
io:format(
"CheckBucketFold returned counts ~w in ~w ms~n",
[element(2, R), Time div 1000]
),
R
end,
{SampleKeysF1, CountMapF1} = CheckBucketFun(Bookie1),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B1">>, CountMapF1),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B2">>, CountMapF1),
TestSampleKeyFun =
fun(Book, Values) ->
fun({B, K}) ->
ExpectedV = maps:get(B, Values),
{ok, Obj} = testutil:book_riakget(Book, B, K),
true = ExpectedV == testutil:get_value(Obj)
end
end,
{GT1, ok} =
timer:tc(
fun() ->
lists:foreach(TestSampleKeyFun(Bookie1, ValueMap), SampleKeysF1)
end
),
io:format(
"Returned ~w sample gets in ~w ms~n",
[length(SampleKeysF1), GT1 div 1000]
),
ok = leveled_bookie:book_close(Bookie1),
{ok, Bookie2} =
leveled_bookie:book_start(
lists:ukeysort(1, [{max_sstslots, 64}|StartOpts1])
),
{SampleKeysF2, CountMapF2} = CheckBucketFun(Bookie2),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B1">>, CountMapF2),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B2">>, CountMapF2),
{GT2, ok} =
timer:tc(
fun() ->
lists:foreach(TestSampleKeyFun(Bookie2, ValueMap), SampleKeysF2)
end
),
io:format(
"Returned ~w sample gets in ~w ms~n",
[length(SampleKeysF2), GT2 div 1000]
),
V3 = LoadBucketFun(Bookie2, <<"B3">>, LoopsPerBucket),
io:format("Completed load of ~s~n", [<<"B3">>]),
UpdValueMap = #{<<"B1">> => V1, <<"B2">> => V2, <<"B3">> => V3},
{SampleKeysF3, CountMapF3} = CheckBucketFun(Bookie2),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B1">>, CountMapF3),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B2">>, CountMapF3),
true = (LoopsPerBucket * PutsPerLoop) == maps:get(<<"B3">>, CountMapF3),
{GT3, ok} =
timer:tc(
fun() ->
lists:foreach(TestSampleKeyFun(Bookie2, UpdValueMap), SampleKeysF3)
end
),
io:format(
"Returned ~w sample gets in ~w ms~n",
[length(SampleKeysF3), GT3 div 1000]
),
ok = leveled_bookie:book_destroy(Bookie2).
basic_riak(_Config) ->
basic_riak_tester(<<"B0">>, 640000),
basic_riak_tester({<<"Type0">>, <<"B0">>}, 80000).
basic_riak_tester(Bucket, KeyCount) ->
% Key Count should be > 10K and divisible by 5
io:format("Basic riak test with Bucket ~w KeyCount ~w~n",

6
test/end_to_end/testutil.erl
View file

@ -883,7 +883,11 @@ put_indexed_objects(Book, Bucket, Count, V) ->
KSpecL =
lists:map(
fun({_RN, Obj, Spc}) ->
book_riakput(Book, Obj, Spc),
R = book_riakput(Book,Obj, Spc),
case R of
ok -> ok;
pause -> timer:sleep(?SLOWOFFER_DELAY)
end,
{testutil:get_key(Obj), Spc}
end,
ObjL1),