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-rw-r--r--lib/mnesia/doc/src/Mnesia_chap5.xmlsrc1
-rw-r--r--lib/mnesia/doc/src/mnesia.xml16
-rw-r--r--lib/mnesia/src/mnesia_controller.erl29
-rw-r--r--lib/mnesia/src/mnesia_dumper.erl60
-rw-r--r--lib/mnesia/src/mnesia_loader.erl7
-rw-r--r--lib/mnesia/src/mnesia_monitor.erl4
-rw-r--r--lib/mnesia/src/mnesia_recover.erl31
7 files changed, 115 insertions, 33 deletions
diff --git a/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc b/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
index 65b950bd46..127c23e0f7 100644
--- a/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
+++ b/lib/mnesia/doc/src/Mnesia_chap5.xmlsrc
@@ -867,6 +867,7 @@ ok
</section>
<section>
+ <marker id="event_handling"></marker>
<title>Mnesia Event Handling</title>
<p>System events and table events are the two categories of events
that Mnesia will generate in various situations.
diff --git a/lib/mnesia/doc/src/mnesia.xml b/lib/mnesia/doc/src/mnesia.xml
index c23c2cb226..856a7594a7 100644
--- a/lib/mnesia/doc/src/mnesia.xml
+++ b/lib/mnesia/doc/src/mnesia.xml
@@ -863,7 +863,7 @@ mnesia:create_table(person,
{attributes, record_info(fields,person)}]).
</code>
<p>The specification of <c>index</c> and <c>attributes</c> may be
- hard coded as <c>{index, [2]}</c> and
+ hard coded as <c>{index, [4]}</c> and
<c>{attributes, [name, age, address, salary, children]}</c>
respectively.
</p>
@@ -2188,12 +2188,13 @@ mnesia:create_table(employee,
</desc>
</func>
<func>
- <name>subscribe(EventCategory)</name>
+ <name>subscribe(EventCategory) -> {ok, Node} | {error, Reason} </name>
<fsummary>Subscribe to events of type <c>EventCategory</c>.</fsummary>
<desc>
<p>Ensures that a copy of all events of type
<c>EventCategory</c> are sent to the caller. The event
- types available are described in the Mnesia User's Guide.</p>
+ types available are described in the Mnesia User's Guide at <seealso marker="Mnesia_chap5#event_handling">Mnesia Event Handling</seealso>.</p>
+ <p><c>Node</c> is the local node. For table events to be subscribed, mnesia must have a readable local copy of the table on the node.</p>
</desc>
</func>
<func>
@@ -2861,11 +2862,12 @@ raise(Name, Amount) ->
</desc>
</func>
<func>
- <name>unsubscribe(EventCategory)</name>
+ <name>unsubscribe(EventCategory) -> {ok, Node} | {error, Reason} </name>
<fsummary>Subscribe to events of type <c>EventCategory</c>.</fsummary>
<desc>
<p>Stops sending events of type
<c>EventCategory</c> to the caller.</p>
+ <p><c>Node</c> is the local node.</p>
</desc>
</func>
<func>
@@ -3017,6 +3019,12 @@ raise(Name, Amount) ->
totally unpredictable.</p>
</item>
<item>
+ <p><c>-mnesia dump_disc_copies_at_startup true | false</c>.
+ If set to false, this disables the dumping of <c>disc_copies</c>
+ tables during startup while tables are being loaded. The default
+ is true.</p>
+ </item>
+ <item>
<p><c>-mnesia dump_log_load_regulation true | false</c>.
Controls if the log dumps should be performed as fast as
possible or if the dumper should do its own load
diff --git a/lib/mnesia/src/mnesia_controller.erl b/lib/mnesia/src/mnesia_controller.erl
index 5a9bae54da..aa72de7594 100644
--- a/lib/mnesia/src/mnesia_controller.erl
+++ b/lib/mnesia/src/mnesia_controller.erl
@@ -51,6 +51,7 @@
force_load_table/1,
async_dump_log/1,
sync_dump_log/1,
+ snapshot_dcd/1,
connect_nodes/1,
connect_nodes/2,
wait_for_schema_commit_lock/0,
@@ -139,7 +140,8 @@ max_loaders() ->
-record(block_controller, {owner}).
-record(dump_log, {initiated_by,
- opt_reply_to
+ opt_reply_to,
+ operation = dump_log
}).
-record(net_load, {table,
@@ -201,6 +203,15 @@ async_dump_log(InitBy) ->
?SERVER_NAME ! {async_dump_log, InitBy},
ok.
+snapshot_dcd(Tables) when is_list(Tables) ->
+ case [T || T <- Tables,
+ mnesia_lib:storage_type_at_node(node(), T) =/= disc_copies] of
+ [] ->
+ call({snapshot_dcd, Tables});
+ BadTabs ->
+ {error, {not_disc_copies, BadTabs}}
+ end.
+
%% Wait for tables to be active
%% If needed, we will wait for Mnesia to start
%% If Mnesia stops, we will wait for Mnesia to restart
@@ -646,6 +657,15 @@ handle_call({sync_dump_log, InitBy}, From, State) ->
State2 = add_worker(Worker, State),
noreply(State2);
+handle_call({snapshot_dcd, Tables}, From, State) ->
+ Worker = #dump_log{initiated_by = user,
+ opt_reply_to = From,
+ operation = fun() ->
+ mnesia_dumper:snapshot_dcd(Tables)
+ end},
+ State2 = add_worker(Worker, State),
+ noreply(State2);
+
handle_call(wait_for_schema_commit_lock, From, State) ->
Worker = #schema_commit_lock{owner = From},
State2 = add_worker(Worker, State),
@@ -2089,7 +2109,12 @@ start_remote_sender(Node, Tab, Receiver, Storage) ->
dump_and_reply(ReplyTo, Worker) ->
%% No trap_exit, die intentionally instead
- Res = mnesia_dumper:opt_dump_log(Worker#dump_log.initiated_by),
+ Res = case Worker#dump_log.operation of
+ dump_log ->
+ mnesia_dumper:opt_dump_log(Worker#dump_log.initiated_by);
+ F when is_function(F, 0) ->
+ F()
+ end,
ReplyTo ! #dumper_done{worker_pid = self(),
worker_res = Res},
unlink(ReplyTo),
diff --git a/lib/mnesia/src/mnesia_dumper.erl b/lib/mnesia/src/mnesia_dumper.erl
index 14665797a0..509b765dee 100644
--- a/lib/mnesia/src/mnesia_dumper.erl
+++ b/lib/mnesia/src/mnesia_dumper.erl
@@ -34,11 +34,13 @@
-export([
get_log_writes/0,
incr_log_writes/0,
+ needs_dump_ets/1,
raw_dump_table/2,
raw_named_dump_table/2,
start_regulator/0,
opt_dump_log/1,
- update/3
+ update/3,
+ snapshot_dcd/1
]).
%% Internal stuff
@@ -99,6 +101,19 @@ opt_dump_log(InitBy) ->
end,
perform_dump(InitBy, Reg).
+snapshot_dcd(Tables) ->
+ lists:foreach(
+ fun(Tab) ->
+ case mnesia_lib:storage_type_at_node(node(), Tab) of
+ disc_copies ->
+ mnesia_log:ets2dcd(Tab);
+ _ ->
+ %% Storage type was checked before queueing the op, though
+ skip
+ end
+ end, Tables),
+ dumped.
+
%% Scan for decisions
perform_dump(InitBy, Regulator) when InitBy == scan_decisions ->
?eval_debug_fun({?MODULE, perform_dump}, [InitBy]),
@@ -981,28 +996,10 @@ open_files(_Tab, _Storage, _UpdateInPlace, _InitBy) ->
false.
open_disc_copies(Tab, InitBy) ->
- DclF = mnesia_lib:tab2dcl(Tab),
- DumpEts =
- case file:read_file_info(DclF) of
- {error, enoent} ->
- false;
- {ok, DclInfo} ->
- DcdF = mnesia_lib:tab2dcd(Tab),
- case file:read_file_info(DcdF) of
- {error, Reason} ->
- mnesia_lib:dbg_out("File ~p info_error ~p ~n",
- [DcdF, Reason]),
- true;
- {ok, DcdInfo} ->
- Mul = case ?catch_val(dc_dump_limit) of
- {'EXIT', _} -> ?DumpToEtsMultiplier;
- Val -> Val
- end,
- DcdInfo#file_info.size =< (DclInfo#file_info.size * Mul)
- end
- end,
+ DumpEts = needs_dump_ets(Tab),
if
DumpEts == false; InitBy == startup ->
+ DclF = mnesia_lib:tab2dcl(Tab),
mnesia_log:open_log({?MODULE,Tab},
mnesia_log:dcl_log_header(),
DclF,
@@ -1017,6 +1014,27 @@ open_disc_copies(Tab, InitBy) ->
false
end.
+needs_dump_ets(Tab) ->
+ DclF = mnesia_lib:tab2dcl(Tab),
+ case file:read_file_info(DclF) of
+ {error, enoent} ->
+ false;
+ {ok, DclInfo} ->
+ DcdF = mnesia_lib:tab2dcd(Tab),
+ case file:read_file_info(DcdF) of
+ {error, Reason} ->
+ mnesia_lib:dbg_out("File ~p info_error ~p ~n",
+ [DcdF, Reason]),
+ true;
+ {ok, DcdInfo} ->
+ Mul = case ?catch_val(dc_dump_limit) of
+ {'EXIT', _} -> ?DumpToEtsMultiplier;
+ Val -> Val
+ end,
+ DcdInfo#file_info.size =< (DclInfo#file_info.size * Mul)
+ end
+ end.
+
%% Always opens the dcl file for writing overriding already_dumped
%% mechanismen, used for schema transactions.
open_dcl(Tab) ->
diff --git a/lib/mnesia/src/mnesia_loader.erl b/lib/mnesia/src/mnesia_loader.erl
index 530317bcdd..cbb3d7e430 100644
--- a/lib/mnesia/src/mnesia_loader.erl
+++ b/lib/mnesia/src/mnesia_loader.erl
@@ -69,9 +69,10 @@ do_get_disc_copy2(Tab, Reason, Storage, Type) when Storage == disc_copies ->
ignore;
_ ->
mnesia_monitor:mktab(Tab, Args),
- Count = mnesia_log:dcd2ets(Tab, Repair),
- case ets:info(Tab, size) of
- X when X < Count * 4 ->
+ _Count = mnesia_log:dcd2ets(Tab, Repair),
+ case mnesia_monitor:get_env(dump_disc_copies_at_startup)
+ andalso mnesia_dumper:needs_dump_ets(Tab) of
+ true ->
ok = mnesia_log:ets2dcd(Tab);
_ ->
ignore
diff --git a/lib/mnesia/src/mnesia_monitor.erl b/lib/mnesia/src/mnesia_monitor.erl
index 6fc1a394a6..a0e0e630ec 100644
--- a/lib/mnesia/src/mnesia_monitor.erl
+++ b/lib/mnesia/src/mnesia_monitor.erl
@@ -664,6 +664,7 @@ env() ->
backup_module,
debug,
dir,
+ dump_disc_copies_at_startup,
dump_log_load_regulation,
dump_log_time_threshold,
dump_log_update_in_place,
@@ -692,6 +693,8 @@ default_env(debug) ->
default_env(dir) ->
Name = lists:concat(["Mnesia.", node()]),
filename:absname(Name);
+default_env(dump_disc_copies_at_startup) ->
+ true;
default_env(dump_log_load_regulation) ->
false;
default_env(dump_log_time_threshold) ->
@@ -741,6 +744,7 @@ do_check_type(debug, trace) -> trace;
do_check_type(debug, true) -> debug;
do_check_type(debug, verbose) -> verbose;
do_check_type(dir, V) -> filename:absname(V);
+do_check_type(dump_disc_copies_at_startup, B) -> bool(B);
do_check_type(dump_log_load_regulation, B) -> bool(B);
do_check_type(dump_log_time_threshold, I) when is_integer(I), I > 0 -> I;
do_check_type(dump_log_update_in_place, B) -> bool(B);
diff --git a/lib/mnesia/src/mnesia_recover.erl b/lib/mnesia/src/mnesia_recover.erl
index b6492707e2..eeb4fa0ced 100644
--- a/lib/mnesia/src/mnesia_recover.erl
+++ b/lib/mnesia/src/mnesia_recover.erl
@@ -689,12 +689,29 @@ handle_call({connect_nodes, Ns}, From, State) ->
%% called from handle_info
gen_server:reply(From, {[], AlreadyConnected}),
{noreply, State};
- GoodNodes ->
+ ProbablyGoodNodes ->
%% Now we have agreed upon a protocol with some new nodes
- %% and we may use them when we recover transactions
+ %% and we may use them when we recover transactions.
+ %%
+ %% Just in case Mnesia was stopped on some of those nodes
+ %% between the protocol negotiation and now, we check one
+ %% more time the state of Mnesia.
+ %%
+ %% Of course, there is still a chance that mnesia_down
+ %% events occur during this check and we miss them. To
+ %% prevent it, handle_cast({mnesia_down, ...}, ...) removes
+ %% the down node again, in addition to mnesia_down/1.
+ %%
+ %% See a comment in handle_cast({mnesia_down, ...}, ...).
+ Verify = fun(N) ->
+ Run = mnesia_lib:is_running(N),
+ Run =:= yes orelse Run =:= starting
+ end,
+ GoodNodes = [N || N <- ProbablyGoodNodes, Verify(N)],
+
mnesia_lib:add_list(recover_nodes, GoodNodes),
cast({announce_all, GoodNodes}),
- case get_master_nodes(schema) of
+ case get_master_nodes(schema) of
[] ->
Context = starting_partitioned_network,
mnesia_monitor:detect_inconcistency(GoodNodes, Context);
@@ -842,6 +859,14 @@ handle_cast({what_decision, Node, OtherD}, State) ->
{noreply, State};
handle_cast({mnesia_down, Node}, State) ->
+ %% The node was already removed from recover_nodes in mnesia_down/1,
+ %% but we do it again here in the mnesia_recover process, in case
+ %% another event incorrectly added it back. This can happen during
+ %% Mnesia startup which takes time betweenthe connection, the
+ %% protocol negotiation and the merge of the schema.
+ %%
+ %% See a comment in handle_call({connect_nodes, ...), ...).
+ mnesia_lib:del(recover_nodes, Node),
case State#state.unclear_decision of
undefined ->
{noreply, State};
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-22 18:49:48 +0000