void replica::send_prepare_message(const dsn_address_t& addr, partition_status status, mutation_ptr& mu, int timeout_milliseconds)
{
dsn_message_t msg = dsn_msg_create_request(RPC_PREPARE, timeout_milliseconds, gpid_to_hash(get_gpid()));
replica_configuration rconfig;
_primary_states.get_replica_config(status, rconfig);
{
msg_binary_writer writer(msg);
marshall(writer, get_gpid());
marshall(writer, rconfig);
mu->write_to(writer);
}
mu->remote_tasks()[addr] = rpc::call(addr, msg,
this,
std::bind(&replica::on_prepare_reply,
this,
std::make_pair(mu, rconfig.status),
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3),
gpid_to_hash(get_gpid())
);
ddebug(
"%s: mutation %s send_prepare_message to %s:%hu as %s",
name(), mu->name(),
addr.name, addr.port,
enum_to_string(rconfig.status)
);
}
void replica::send_prepare_message(
::dsn::rpc_address addr,
partition_status status,
mutation_ptr& mu,
int timeout_milliseconds,
int64_t learn_signature)
{
dsn_message_t msg = dsn_msg_create_request(RPC_PREPARE, timeout_milliseconds, gpid_to_hash(get_gpid()));
replica_configuration rconfig;
_primary_states.get_replica_config(status, rconfig, learn_signature);
{
rpc_write_stream writer(msg);
marshall(writer, get_gpid());
marshall(writer, rconfig);
mu->write_to(writer);
}
mu->remote_tasks()[addr] = rpc::call(addr, msg,
this,
[=](error_code err, dsn_message_t request, dsn_message_t reply)
{
on_prepare_reply(std::make_pair(mu, rconfig.status), err, request, reply);
},
gpid_to_hash(get_gpid())
);
ddebug(
"%s: mutation %s send_prepare_message to %s as %s",
name(), mu->name(),
addr.to_string(),
enum_to_string(rconfig.status)
);
}
void replica::send_prepare_message(const end_point& addr, partition_status status, mutation_ptr& mu, int timeout_milliseconds)
{
message_ptr msg = message::create_request(RPC_PREPARE, timeout_milliseconds, gpid_to_hash(get_gpid()));
marshall(msg, get_gpid());
replica_configuration rconfig;
_primary_states.get_replica_config(status, rconfig);
marshall(msg, rconfig);
mu->write_to(msg);
dbg_dassert (mu->remote_tasks().find(addr) == mu->remote_tasks().end());
mu->remote_tasks()[addr] = rpc::call(addr, msg,
this,
std::bind(&replica::on_prepare_reply,
this,
std::make_pair(mu, rconfig.status),
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3),
gpid_to_hash(get_gpid())
);
ddebug(
"%s: mutation %s send_prepare_message to %s:%d as %s",
name(), mu->name(),
addr.name.c_str(), static_cast<int>(addr.port),
enum_to_string(rconfig.status)
);
}
void replication_app_client_base::call_with_address(dsn::rpc_address addr, request_context_ptr request)
{
auto& msg = request->request;
dbg_dassert(!addr.is_invalid(), "");
dbg_dassert(_app_id > 0, "");
if (request->header_pos != 0)
{
if (request->is_read)
{
request->read_header.gpid.app_id = _app_id;
request->read_header.gpid.pidx = request->partition_index;
blob buffer(request->header_pos, 0, sizeof(request->read_header));
binary_writer writer(buffer);
marshall(writer, request->read_header);
dsn_msg_options_t opts;
opts.timeout_ms = request->timeout_ms;
opts.thread_hash = gpid_to_hash(request->read_header.gpid);
opts.vnid = *(uint64_t*)(&request->read_header.gpid);
dsn_msg_set_options(request->request, &opts, DSN_MSGM_HASH | DSN_MSGM_TIMEOUT); // TODO: not supported yet DSN_MSGM_VNID);
}
else
{
request->write_header.gpid.app_id = _app_id;
request->write_header.gpid.pidx = request->partition_index;
blob buffer(request->header_pos, 0, sizeof(request->write_header));
binary_writer writer(buffer);
marshall(writer, request->write_header);
dsn_msg_options_t opts;
opts.timeout_ms = request->timeout_ms;
opts.thread_hash = gpid_to_hash(request->write_header.gpid);
opts.vnid = *(uint64_t*)(&request->write_header.gpid);
dsn_msg_set_options(request->request, &opts, DSN_MSGM_HASH | DSN_MSGM_TIMEOUT); // TODO: not supported yet DSN_MSGM_VNID | DSN_MSGM_CONTEXT);
}
request->header_pos = 0;
}
{
zauto_lock l(request->lock);
rpc::call(
addr,
msg,
this,
std::bind(
&replication_app_client_base::replica_rw_reply,
this,
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3,
request
)
);
}
}
void replica::catch_up_with_private_logs(partition_status s)
{
learn_state state;
_private_log->get_learn_state(
get_gpid(),
_app->last_committed_decree() + 1,
state
);
auto err = apply_learned_state_from_private_log(state);
tasking::enqueue(
LPC_CHECKPOINT_REPLICA_COMPLETED,
this,
[this, err, s]()
{
if (PS_SECONDARY == s)
this->on_checkpoint_completed(err);
else if (PS_POTENTIAL_SECONDARY == s)
this->on_learn_remote_state_completed(err);
else
{
dassert(false, "invalid state %s", enum_to_string(s));
}
},
gpid_to_hash(get_gpid())
);
}
replication_app_client_base::request_context* replication_app_client_base::create_write_context(
int partition_index,
task_code code,
rpc_response_task_ptr callback,
int reply_hash
)
{
auto rc = new request_context;
rc->callback_task = callback;
rc->is_read = false;
rc->partition_index = partition_index;
rc->write_header.gpid.app_id = _app_id;
rc->write_header.gpid.pidx = partition_index;
rc->write_header.code = code;
rc->timeout_timer = nullptr;
if (rc->write_header.gpid.app_id == -1)
{
rc->header_pos = callback->get_request()->writer().write_placeholder();
dbg_dassert(rc->header_pos != 0xffff, "");
}
else
{
rc->header_pos = 0xffff;
marshall(callback->get_request()->writer(), rc->write_header);
callback->get_request()->header().client.hash = gpid_to_hash(rc->write_header.gpid);
}
return rc;
}
replication_app_client_base::request_context* replication_app_client_base::create_read_context(
int partition_index,
task_code code,
rpc_response_task_ptr callback,
read_semantic_t read_semantic,
decree snapshot_decree, // only used when ReadSnapshot
int reply_hash
)
{
auto rc = new request_context;
rc->callback_task = callback;
rc->is_read = true;
rc->partition_index = partition_index;
rc->read_header.gpid.app_id = _app_id;
rc->read_header.gpid.pidx = partition_index;
rc->read_header.code = code;
rc->read_header.semantic = read_semantic;
rc->read_header.version_decree = snapshot_decree;
rc->timeout_timer = nullptr;
if (rc->read_header.gpid.app_id == -1)
{
rc->header_pos = callback->get_request()->writer().write_placeholder();
dbg_dassert(rc->header_pos != 0xffff, "");
}
else
{
rc->header_pos = 0xffff;
marshall(callback->get_request()->writer(), rc->read_header);
callback->get_request()->header().client.hash = gpid_to_hash(rc->read_header.gpid);
}
return rc;
}
void replica::on_checkpoint_completed(error_code err)
{
check_hashed_access();
// closing or wrong timing
if (PS_SECONDARY != status() || ERR_WRONG_TIMING == err)
{
_secondary_states.checkpoint_task = nullptr;
return;
}
// handle failure
if (err != ERR_OK)
{
// done checkpointing
_secondary_states.checkpoint_task = nullptr;
handle_local_failure(err);
return;
}
auto c = _prepare_list->last_committed_decree();
// missing commits
if (c > _app->last_committed_decree())
{
// missed ones are covered by prepare list
if (_app->last_committed_decree() > _prepare_list->min_decree())
{
for (auto d = _app->last_committed_decree() + 1; d <= c; d++)
{
auto mu = _prepare_list->get_mutation_by_decree(d);
dassert(nullptr != mu, "");
_app->write_internal(mu);
}
// everything is ok now, done checkpointing
_secondary_states.checkpoint_task = nullptr;
}
// missed ones need to be loaded via private logs
else
{
_secondary_states.checkpoint_task = tasking::enqueue(
LPC_CHECKPOINT_REPLICA,
this,
[this]() { this->catch_up_with_private_logs(PS_SECONDARY); },
gpid_to_hash(get_gpid())
);
}
}
// no missing commits
else
{
// everything is ok now, done checkpointing
_secondary_states.checkpoint_task = nullptr;
}
}
void replica::on_copy_checkpoint_ack(error_code err, std::shared_ptr<replica_configuration>& req, std::shared_ptr<learn_response>& resp)
{
check_hashed_access();
if (PS_PRIMARY != status())
{
_primary_states.checkpoint_task = nullptr;
return;
}
if (err != ERR_OK || resp == nullptr)
{
dwarn("%s: copy checkpoint from secondary failed, err = %s", name(), err.to_string());
_primary_states.checkpoint_task = nullptr;
return;
}
if (resp->err != ERR_OK)
{
dinfo("%s: copy checkpoint from secondary failed, err = %s", name(), resp->err.to_string());
_primary_states.checkpoint_task = nullptr;
return;
}
if (resp->state.to_decree_included <= _app->last_durable_decree())
{
dinfo("%s: copy checkpoint from secondary skipped, as its decree is not bigger than current durable_decree: %" PRIu64 " vs %" PRIu64 "",
name(), resp->state.to_decree_included, _app->last_durable_decree()
);
_primary_states.checkpoint_task = nullptr;
return;
}
std::string ldir = utils::filesystem::path_combine(
_app->learn_dir(),
"checkpoint.copy"
);
if (utils::filesystem::path_exists(ldir))
utils::filesystem::remove_path(ldir);
_primary_states.checkpoint_task = file::copy_remote_files(
resp->address,
resp->base_local_dir,
resp->state.files,
ldir,
false,
LPC_REPLICA_COPY_LAST_CHECKPOINT_DONE,
this,
[this, resp](error_code err, size_t sz)
{
this->on_copy_checkpoint_file_completed(err, sz, resp);
},
gpid_to_hash(get_gpid())
);
}
// run in background thread
void replica::background_checkpoint()
{
auto err = _app->checkpoint();
tasking::enqueue(
LPC_CHECKPOINT_REPLICA_COMPLETED,
this,
[this, err]() { this->on_checkpoint_completed(err); },
gpid_to_hash(get_gpid())
);
}
// meta server => partition server
void server_load_balancer::send_proposal(::dsn::rpc_address node, const configuration_update_request& proposal)
{
dinfo("send proposal %s of %s, current ballot = %" PRId64,
enum_to_string(proposal.type),
proposal.node.to_string(),
proposal.config.ballot
);
rpc::call_one_way_typed(node, RPC_CONFIG_PROPOSAL, proposal, gpid_to_hash(proposal.config.gpid));
}
// for testing purpose only
void replica::send_group_check_once_for_test(int delay_milliseconds)
{
dassert (_options.group_check_disabled, "");
_primary_states.group_check_task = tasking::enqueue(
LPC_GROUP_CHECK,
this,
&replica::broadcast_group_check,
gpid_to_hash(get_gpid()),
delay_milliseconds
);
}
// for testing purpose only
void replica::send_group_check_once_for_test(int delay_milliseconds)
{
dassert (_options->group_check_disabled, "");
_primary_states.group_check_task = tasking::enqueue(
LPC_GROUP_CHECK,
this,
[this] {broadcast_group_check();},
gpid_to_hash(get_gpid()),
std::chrono::milliseconds(delay_milliseconds)
);
}
void replica::broadcast_group_check()
{
dassert (nullptr != _primary_states.group_check_task, "");
if (_primary_states.group_check_pending_replies.size() > 0)
{
dwarn(
"%s: %u group check replies are still pending when doing next round check",
name(), static_cast<int>(_primary_states.group_check_pending_replies.size())
);
for (auto it = _primary_states.group_check_pending_replies.begin(); it != _primary_states.group_check_pending_replies.end(); it++)
{
it->second->cancel(true);
}
_primary_states.group_check_pending_replies.clear();
}
for (auto it = _primary_states.statuses.begin(); it != _primary_states.statuses.end(); it++)
{
if (it->first == primary_address())
continue;
end_point addr = it->first;
std::shared_ptr<group_check_request> request(new group_check_request);
request->app_type = _primary_states.membership.app_type;
request->node = addr;
_primary_states.get_replica_config(addr, request->config);
request->last_committed_decree = last_committed_decree();
request->learner_signature = 0;
if (it->second == PS_POTENTIAL_SECONDARY)
{
auto it2 = _primary_states.learners.find(it->first);
dassert (it2 != _primary_states.learners.end(), "");
request->learner_signature = it2->second.signature;
}
task_ptr callback_task = rpc::call_typed(
addr,
RPC_GROUP_CHECK,
request,
this,
&replica::on_group_check_reply,
gpid_to_hash(get_gpid())
);
_primary_states.group_check_pending_replies[addr] = callback_task;
ddebug(
"%s: init_group_check for %s:%d", name(), addr.name.c_str(), addr.port
);
}
}
void replica::checkpoint()
{
auto lerr = _app->flush(true);
auto err = lerr == 0 ? ERR_OK :
(lerr == ERR_WRONG_TIMING ? ERR_WRONG_TIMING : ERR_LOCAL_APP_FAILURE);
tasking::enqueue(
LPC_CHECKPOINT_REPLICA_COMPLETED,
this,
[this, err]() { this->on_checkpoint_completed(err); },
gpid_to_hash(get_gpid())
);
}
void replica::catch_up_with_private_logs(partition_status s)
{
learn_state state;
_private_log->get_learn_state(
get_gpid(),
_app->last_committed_decree() + 1,
state
);
auto err = apply_learned_state_from_private_log(state);
if (s == PS_POTENTIAL_SECONDARY)
{
tasking::enqueue(
&_potential_secondary_states.learn_remote_files_completed_task,
LPC_CHECKPOINT_REPLICA_COMPLETED,
this,
[this, err]()
{
this->on_learn_remote_state_completed(err);
},
gpid_to_hash(get_gpid())
);
}
else
{
tasking::enqueue(
&_secondary_states.checkpoint_completed_task,
LPC_CHECKPOINT_REPLICA_COMPLETED,
this,
[this, err]()
{
this->on_checkpoint_completed(err);
},
gpid_to_hash(get_gpid())
);
}
}
void simple_load_balancer::query_decree(std::shared_ptr<query_replica_decree_request> query)
{
rpc::call(
query->node,
RPC_QUERY_PN_DECREE,
*query,
this,
[this, query](error_code err, query_replica_decree_response&& resp)
{
auto response = std::make_shared<query_replica_decree_response>(std::move(resp));
on_query_decree_ack(err, query, response);
}
,
gpid_to_hash(query->pid), std::chrono::seconds(3));
}
void replica::init_group_check()
{
if (PS_PRIMARY != status() || _options.group_check_disabled)
return;
dassert (nullptr == _primary_states.group_check_task, "");
_primary_states.group_check_task = tasking::enqueue(
LPC_GROUP_CHECK,
this,
&replica::broadcast_group_check,
gpid_to_hash(get_gpid()),
0,
_options.group_check_internal_ms
);
}
void replica::init_checkpoint()
{
check_hashed_access();
// only applicable to primary and secondary replicas
if (status() != PS_PRIMARY && status() != PS_SECONDARY)
return;
// no need to checkpoint
if (_app->is_delta_state_learning_supported())
return;
// already running
if (_secondary_states.checkpoint_task != nullptr)
return;
// private log must be enabled to make sure commits
// are not lost during checkpinting
dassert(nullptr != _private_log, "log_enable_private_prepare must be true for checkpointing");
// TODO: when NOT to checkpoint, but use private log replay to build the state
if (last_committed_decree() - last_durable_decree() < 10000)
return;
// primary is downgraded to secondary for checkpointing as no write can be seen
// during checkpointing (i.e., state is freezed)
if (PS_PRIMARY == status())
{
configuration_update_request proposal;
proposal.config = _primary_states.membership;
proposal.type = CT_DOWNGRADE_TO_SECONDARY;
proposal.node = proposal.config.primary;
downgrade_to_secondary_on_primary(proposal);
}
// secondary can start checkpint in the long running thread pool
else
{
dassert(PS_SECONDARY == status(), "");
_secondary_states.checkpoint_task = tasking::enqueue(
LPC_CHECKPOINT_REPLICA,
this,
&replica::checkpoint,
gpid_to_hash(get_gpid())
);
}
}
mutation_queue::mutation_queue(gpid gpid, int max_concurrent_op /*= 2*/, bool batch_write_disabled /*= false*/)
: _max_concurrent_op(max_concurrent_op), _batch_write_disabled(batch_write_disabled)
{
std::stringstream ss;
ss << gpid.get_app_id() << "." << gpid.get_partition_index() << "." << "2pc#";
_current_op_counter.init("eon.replication", ss.str().c_str(), COUNTER_TYPE_NUMBER, "current running 2pc#");
_current_op_counter.set(0);
_current_op_count = 0;
_pending_mutation = nullptr;
dassert(gpid.get_app_id() != 0, "invalid gpid");
_pcount = dsn_task_queue_virtual_length_ptr(
RPC_PREPARE,
gpid_to_hash(gpid)
);
}
void replica::update_configuration_on_meta_server(config_type type, ::dsn::rpc_address node, partition_configuration& newConfig)
{
newConfig.last_committed_decree = last_committed_decree();
if (type != CT_ASSIGN_PRIMARY && type != CT_UPGRADE_TO_PRIMARY)
{
dassert (status() == PS_PRIMARY, "");
dassert (newConfig.ballot == _primary_states.membership.ballot, "");
}
// disable 2pc during reconfiguration
// it is possible to do this only for CT_DOWNGRADE_TO_SECONDARY,
// but we choose to disable 2pc during all reconfiguration types
// for simplicity at the cost of certain write throughput
update_local_configuration_with_no_ballot_change(PS_INACTIVE);
set_inactive_state_transient(true);
dsn_message_t msg = dsn_msg_create_request(RPC_CM_UPDATE_PARTITION_CONFIGURATION, 0, 0);
std::shared_ptr<configuration_update_request> request(new configuration_update_request);
request->config = newConfig;
request->config.ballot++;
request->type = type;
request->node = node;
::marshall(msg, *request);
if (nullptr != _primary_states.reconfiguration_task)
{
_primary_states.reconfiguration_task->cancel(true);
}
rpc_address target(_stub->_failure_detector->get_servers());
_primary_states.reconfiguration_task = rpc::call(
target,
msg,
this,
std::bind(&replica::on_update_configuration_on_meta_server_reply, this,
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3,
request),
gpid_to_hash(get_gpid())
);
}
void replica::init_group_check()
{
check_hashed_access();
ddebug("%s: init group check", name());
if (partition_status::PS_PRIMARY != status() || _options->group_check_disabled)
return;
dassert (nullptr == _primary_states.group_check_task, "");
_primary_states.group_check_task = tasking::enqueue_timer(
LPC_GROUP_CHECK,
this,
[this] {broadcast_group_check();},
std::chrono::milliseconds(_options->group_check_interval_ms),
gpid_to_hash(get_gpid())
);
}
void replica::add_potential_secondary(configuration_update_request& proposal)
{
if (status() != PS_PRIMARY)
{
return;
}
dassert (proposal.config.ballot == get_ballot(), "");
dassert (proposal.config.gpid == _primary_states.membership.gpid, "");
dassert (proposal.config.app_type == _primary_states.membership.app_type, "");
dassert (proposal.config.primary == _primary_states.membership.primary, "");
dassert (proposal.config.secondaries == _primary_states.membership.secondaries, "");
dassert (!_primary_states.check_exist(proposal.node, PS_PRIMARY), "");
dassert (!_primary_states.check_exist(proposal.node, PS_SECONDARY), "");
if (_primary_states.learners.find(proposal.node) != _primary_states.learners.end())
{
return;
}
remote_learner_state state;
state.prepare_start_decree = invalid_decree;
state.signature = random64(0, (uint64_t)(-1LL));
state.timeout_task = nullptr; // TODO: add timer for learner task
_primary_states.learners[proposal.node] = state;
_primary_states.statuses[proposal.node] = PS_POTENTIAL_SECONDARY;
group_check_request request;
request.app_type = _primary_states.membership.app_type;
request.node = proposal.node;
_primary_states.get_replica_config(proposal.node, request.config);
request.last_committed_decree = last_committed_decree();
request.learner_signature = state.signature;
rpc::call_one_way_typed(proposal.node, RPC_LEARN_ADD_LEARNER, request, gpid_to_hash(get_gpid()));
}
void replica::init_prepare(mutation_ptr& mu)
{
dassert (PS_PRIMARY == status(), "");
error_code err = ERR_OK;
uint8_t count = 0;
mu->data.header.last_committed_decree = last_committed_decree();
if (mu->data.header.decree == invalid_decree)
{
mu->set_id(get_ballot(), _prepare_list->max_decree() + 1);
}
else
{
mu->set_id(get_ballot(), mu->data.header.decree);
}
dinfo("%s: mutation %s init_prepare, mutation_tid=%" PRIu64, name(), mu->name(), mu->tid());
// check bounded staleness
if (mu->data.header.decree > last_committed_decree() + _options->staleness_for_commit)
{
err = ERR_CAPACITY_EXCEEDED;
goto ErrOut;
}
dassert (mu->data.header.decree > last_committed_decree(), "");
// local prepare
err = _prepare_list->prepare(mu, PS_PRIMARY);
if (err != ERR_OK)
{
goto ErrOut;
}
// remote prepare
mu->set_prepare_ts();
mu->set_left_secondary_ack_count((unsigned int)_primary_states.membership.secondaries.size());
for (auto it = _primary_states.membership.secondaries.begin(); it != _primary_states.membership.secondaries.end(); ++it)
{
send_prepare_message(*it, PS_SECONDARY, mu, _options->prepare_timeout_ms_for_secondaries);
}
count = 0;
for (auto it = _primary_states.learners.begin(); it != _primary_states.learners.end(); ++it)
{
if (it->second.prepare_start_decree != invalid_decree && mu->data.header.decree >= it->second.prepare_start_decree)
{
send_prepare_message(it->first, PS_POTENTIAL_SECONDARY, mu, _options->prepare_timeout_ms_for_potential_secondaries, it->second.signature);
count++;
}
}
mu->set_left_potential_secondary_ack_count(count);
if (mu->is_logged())
{
do_possible_commit_on_primary(mu);
}
else
{
dassert(mu->data.header.log_offset == invalid_offset, "");
dassert(mu->log_task() == nullptr, "");
mu->log_task() = _stub->_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
this,
std::bind(&replica::on_append_log_completed, this, mu,
std::placeholders::_1,
std::placeholders::_2),
gpid_to_hash(get_gpid())
);
dassert(nullptr != mu->log_task(), "");
}
return;
ErrOut:
for (auto& r : mu->client_requests)
{
response_client_message(r, err);
}
return;
}
void replica::on_append_log_completed(mutation_ptr& mu, error_code err, size_t size)
{
check_hashed_access();
dinfo("%s: append shared log completed for mutation %s, size = %u, err = %s",
name(), mu->name(), size, err.to_string());
if (err == ERR_OK)
{
mu->set_logged();
}
else
{
derror("%s: append shared log failed for mutation %s, err = %s",
name(), mu->name(), err.to_string());
}
// skip old mutations
if (mu->data.header.ballot >= get_ballot() && status() != PS_INACTIVE)
{
switch (status())
{
case PS_PRIMARY:
if (err == ERR_OK)
{
do_possible_commit_on_primary(mu);
}
else
{
handle_local_failure(err);
}
break;
case PS_SECONDARY:
case PS_POTENTIAL_SECONDARY:
if (err != ERR_OK)
{
handle_local_failure(err);
}
// always ack
ack_prepare_message(err, mu);
break;
case PS_ERROR:
break;
default:
dassert(false, "");
break;
}
}
if (err != ERR_OK)
{
// mutation log failure, propagate to all replicas
_stub->handle_log_failure(err);
}
// write local private log if necessary
if (err == ERR_OK && _private_log && status() != PS_ERROR)
{
_private_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
nullptr,
[this, mu](error_code err, size_t size)
{
//
// DO NOT CHANGE THIS CALLBACK HERE UNLESS
// YOU FULLY UNDERSTAND WHAT WE DO HERE
//
// AS PRIVATE LOG IS BATCHED, WE ONLY EXECUTE
// THE FIRST CALLBACK IF THERE IS FAILURE TO
// NOTIFY FAILURE. ALL OTHER TASKS ARE SIMPLY
// CANCELLED!!!
//
// TODO: we do not need so many callbacks
//
dinfo("%s: append private log completed for mutation %s, size = %u, err = %s",
name(), mu->name(), size, err.to_string());
if (err != ERR_OK)
{
derror("%s: append private log failed for mutation %s, err = %s",
name(), mu->name(), err.to_string());
handle_local_failure(err);
}
},
gpid_to_hash(get_gpid())
);
}
}
void replica::on_prepare(dsn_message_t request)
{
check_hashed_access();
replica_configuration rconfig;
mutation_ptr mu;
{
rpc_read_stream reader(request);
unmarshall(reader, rconfig);
mu = mutation::read_from(reader, request);
}
decree decree = mu->data.header.decree;
dinfo("%s: mutation %s on_prepare", name(), mu->name());
dassert(mu->data.header.ballot == rconfig.ballot, "");
if (mu->data.header.ballot < get_ballot())
{
derror("%s: mutation %s on_prepare skipped due to old view", name(), mu->name());
// no need response because the rpc should have been cancelled on primary in this case
return;
}
// update configuration when necessary
else if (rconfig.ballot > get_ballot())
{
if (!update_local_configuration(rconfig))
{
derror(
"%s: mutation %s on_prepare failed as update local configuration failed, state = %s",
name(), mu->name(),
enum_to_string(status())
);
ack_prepare_message(ERR_INVALID_STATE, mu);
return;
}
}
if (PS_INACTIVE == status() || PS_ERROR == status())
{
derror(
"%s: mutation %s on_prepare failed as invalid replica state, state = %s",
name(), mu->name(),
enum_to_string(status())
);
ack_prepare_message(
(PS_INACTIVE == status() && _inactive_is_transient) ? ERR_INACTIVE_STATE : ERR_INVALID_STATE,
mu
);
return;
}
else if (PS_POTENTIAL_SECONDARY == status())
{
// new learning process
if (rconfig.learner_signature != _potential_secondary_states.learning_signature)
{
init_learn(rconfig.learner_signature);
// no need response as rpc is already gone
return;
}
if (!(_potential_secondary_states.learning_status == LearningWithPrepare
|| _potential_secondary_states.learning_status == LearningSucceeded))
{
derror(
"%s: mutation %s on_prepare skipped as invalid learning status, state = %s, learning_status = %s",
name(), mu->name(),
enum_to_string(status()),
enum_to_string(_potential_secondary_states.learning_status)
);
// no need response as rpc is already gone
return;
}
}
dassert (rconfig.status == status(), "");
if (decree <= last_committed_decree())
{
ack_prepare_message(ERR_OK, mu);
return;
}
// real prepare start
auto mu2 = _prepare_list->get_mutation_by_decree(decree);
if (mu2 != nullptr && mu2->data.header.ballot == mu->data.header.ballot)
{
if (mu2->is_logged())
{
ack_prepare_message(ERR_OK, mu);
}
else
{
derror("%s: mutation %s on_prepare skipped as it is duplicate", name(), mu->name());
// response will be unnecessary when we add retry logic in rpc engine.
// the retried rpc will use the same id therefore it will be considered responsed
// even the response is for a previous try.
}
return;
}
error_code err = _prepare_list->prepare(mu, status());
dassert (err == ERR_OK, "");
if (PS_POTENTIAL_SECONDARY == status())
{
dassert (mu->data.header.decree <= last_committed_decree() + _options->max_mutation_count_in_prepare_list, "");
}
else
{
dassert (PS_SECONDARY == status(), "");
dassert (mu->data.header.decree <= last_committed_decree() + _options->staleness_for_commit, "");
}
dassert(mu->log_task() == nullptr, "");
mu->log_task() = _stub->_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
this,
std::bind(&replica::on_append_log_completed, this, mu,
std::placeholders::_1,
std::placeholders::_2),
gpid_to_hash(get_gpid())
);
}
void replication_app_client_base::call(request_context* request, bool no_delay)
{
auto& msg = request->callback_task->get_request();
auto nts = ::dsn::service::env::now_us();
if (nts + 100 >= msg->header().client.timeout_ts_us) // < 100us
{
message_ptr nil(nullptr);
end_request(request, ERR_TIMEOUT, nil);
delete request;
return;
}
end_point addr;
int app_id;
error_code err = get_address(
request->partition_index,
!request->is_read,
addr,
app_id,
request->read_header.semantic
);
// target node in cache
if (err == ERR_SUCCESS)
{
dbg_dassert(addr != end_point::INVALID, "");
dassert(app_id > 0, "");
if (request->header_pos != 0xffff)
{
if (request->is_read)
{
request->read_header.gpid.app_id = app_id;
marshall(msg->writer(), request->read_header, request->header_pos);
msg->header().client.hash = gpid_to_hash(request->read_header.gpid);
}
else
{
request->write_header.gpid.app_id = app_id;
marshall(msg->writer(), request->write_header, request->header_pos);
msg->header().client.hash = gpid_to_hash(request->write_header.gpid);
}
request->header_pos = 0xffff;
}
rpc::call(
addr,
msg,
this,
std::bind(
&replication_app_client_base::replica_rw_reply,
this,
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3,
request
)
);
}
// target node not known
else if (!no_delay)
{
// delay 1 second for further config query
tasking::enqueue(LPC_REPLICATION_DELAY_QUERY_CONFIG, this,
std::bind(&replication_app_client_base::call, this, request, true),
0,
1000
);
}
else
{
zauto_lock l(_requests_lock);
// init timeout timer if necessary
if (request->timeout_timer == nullptr)
{
request->timeout_timer = tasking::enqueue(
LPC_REPLICATION_CLIENT_REQUEST_TIMEOUT,
this,
std::bind(&replication_app_client_base::on_user_request_timeout, this, request),
0,
static_cast<int>((msg->header().client.timeout_ts_us - nts) / 1000)
);
}
// put into pending queue of querying target partition
auto it = _pending_requests.find(request->partition_index);
if (it == _pending_requests.end())
{
auto pc = new partition_context;
pc->query_config_task = nullptr;
it = _pending_requests.insert(pending_requests::value_type(request->partition_index, pc)).first;
}
it->second->requests.push_back(request);
// init configuration query task if necessary
if (it->second->query_config_task == nullptr)
{
message_ptr msg = message::create_request(RPC_CM_CALL);
meta_request_header hdr;
hdr.rpc_tag = RPC_CM_QUERY_PARTITION_CONFIG_BY_INDEX;
marshall(msg->writer(), hdr);
configuration_query_by_index_request req;
req.app_name = _app_name;
req.partition_indices.push_back(request->partition_index);
marshall(msg->writer(), req);
it->second->query_config_task = rpc::call_replicated(
_last_contact_point,
_meta_servers,
msg,
this,
std::bind(&replication_app_client_base::query_partition_configuration_reply,
this,
std::placeholders::_1,
std::placeholders::_2,
std::placeholders::_3,
request->partition_index
)
);
}
}
}
void replica::on_append_log_completed(mutation_ptr& mu, error_code err, size_t size)
{
check_hashed_access();
dinfo("%s: append shared log completed for mutation %s, size = %u, err = %s",
name(), mu->name(), size, err.to_string());
if (err == ERR_OK)
{
mu->set_logged();
}
else
{
derror("%s: append shared log failed for mutation %s, err = %s",
name(), mu->name(), err.to_string());
}
// skip old mutations
if (mu->data.header.ballot >= get_ballot() && status() != partition_status::PS_INACTIVE)
{
switch (status())
{
case partition_status::PS_PRIMARY:
if (err == ERR_OK)
{
do_possible_commit_on_primary(mu);
}
else
{
handle_local_failure(err);
}
break;
case partition_status::PS_SECONDARY:
case partition_status::PS_POTENTIAL_SECONDARY:
if (err != ERR_OK)
{
handle_local_failure(err);
}
// always ack
ack_prepare_message(err, mu);
break;
case partition_status::PS_ERROR:
break;
default:
dassert(false, "");
break;
}
}
if (err != ERR_OK)
{
// mutation log failure, propagate to all replicas
_stub->handle_log_failure(err);
}
// write local private log if necessary
if (err == ERR_OK && _private_log && status() != partition_status::PS_ERROR)
{
_private_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
nullptr,
nullptr,
gpid_to_hash(get_gpid())
);
}
}
void replica::init_prepare(mutation_ptr& mu)
{
dassert (PS_PRIMARY == status(), "");
error_code err = ERR_OK;
uint8_t count = 0;
if (static_cast<int>(_primary_states.membership.secondaries.size()) + 1 < _options.mutation_2pc_min_replica_count)
{
err = ERR_NOT_ENOUGH_MEMBER;
goto ErrOut;
}
mu->data.header.last_committed_decree = last_committed_decree();
if (mu->data.header.decree == invalid_decree)
{
mu->set_id(get_ballot(), _prepare_list->max_decree() + 1);
}
else
{
mu->set_id(get_ballot(), mu->data.header.decree);
}
ddebug("%s: mutation %s init_prepare", name(), mu->name());
// check bounded staleness
if (mu->data.header.decree > last_committed_decree() + _options.staleness_for_commit)
{
err = ERR_CAPACITY_EXCEEDED;
goto ErrOut;
}
dassert (mu->data.header.decree > last_committed_decree(), "");
// local prepare
err = _prepare_list->prepare(mu, PS_PRIMARY);
if (err != ERR_OK)
{
goto ErrOut;
}
// remote prepare
mu->set_prepare_ts();
mu->set_left_secondary_ack_count((unsigned int)_primary_states.membership.secondaries.size());
for (auto it = _primary_states.membership.secondaries.begin(); it != _primary_states.membership.secondaries.end(); it++)
{
send_prepare_message(*it, PS_SECONDARY, mu, _options.prepare_timeout_ms_for_secondaries);
}
count = 0;
for (auto it = _primary_states.learners.begin(); it != _primary_states.learners.end(); it++)
{
if (it->second.prepare_start_decree != invalid_decree && mu->data.header.decree >= it->second.prepare_start_decree)
{
send_prepare_message(it->first, PS_POTENTIAL_SECONDARY, mu, _options.prepare_timeout_ms_for_potential_secondaries);
count++;
}
}
mu->set_left_potential_secondary_ack_count(count);
// it is possible to do commit here when logging is not required for acking prepare.
// however, it is only possible when replica count == 1 at this moment in the
// replication group, and we don't want to do this as it is too fragile now.
// do_possible_commit_on_primary(mu);
// local log
dassert (mu->data.header.log_offset == invalid_offset, "");
dassert (mu->log_task() == nullptr, "");
mu->log_task() = _stub->_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
this,
std::bind(&replica::on_append_log_completed, this, mu,
std::placeholders::_1,
std::placeholders::_2),
gpid_to_hash(get_gpid())
);
dassert(nullptr != mu->log_task(), "");
return;
ErrOut:
response_client_message(mu->client_msg(), err);
return;
}
void replica::on_prepare(dsn_message_t request)
{
check_hashed_access();
replica_configuration rconfig;
mutation_ptr mu;
{
msg_binary_reader reader(request);
unmarshall(reader, rconfig);
mu = mutation::read_from(reader, request);
}
decree decree = mu->data.header.decree;
ddebug( "%s: mutation %s on_prepare", name(), mu->name());
dassert (mu->data.header.ballot == rconfig.ballot, "");
if (mu->data.header.ballot < get_ballot())
{
ddebug( "%s: mutation %s on_prepare skipped due to old view", name(), mu->name());
return;
}
// update configuration when necessary
else if (rconfig.ballot > get_ballot())
{
if (!update_local_configuration(rconfig))
{
ddebug(
"%s: mutation %s on_prepare to %s failed as update local configuration failed",
name(), mu->name(),
enum_to_string(status())
);
ack_prepare_message(ERR_INVALID_STATE, mu);
return;
}
}
if (PS_INACTIVE == status() || PS_ERROR == status())
{
ddebug(
"%s: mutation %s on_prepare to %s skipped",
name(), mu->name(),
enum_to_string(status())
);
ack_prepare_message(
(PS_INACTIVE == status() && _inactive_is_transient) ? ERR_INACTIVE_STATE : ERR_INVALID_STATE,
mu
);
return;
}
else if (PS_POTENTIAL_SECONDARY == status())
{
if (_potential_secondary_states.learning_status != LearningWithPrepare && _potential_secondary_states.learning_status != LearningSucceeded)
{
ddebug(
"%s: mutation %s on_prepare to %s skipped, learnings state = %s",
name(), mu->name(),
enum_to_string(status()),
enum_to_string(_potential_secondary_states.learning_status)
);
// do not retry as there may retries later
return;
}
}
dassert (rconfig.status == status(), "");
if (decree <= last_committed_decree())
{
ack_prepare_message(ERR_OK, mu);
return;
}
// real prepare start
auto mu2 = _prepare_list->get_mutation_by_decree(decree);
if (mu2 != nullptr && mu2->data.header.ballot == mu->data.header.ballot)
{
ddebug( "%s: mutation %s redundant prepare skipped", name(), mu->name());
if (mu2->is_logged() || _options.prepare_ack_on_secondary_before_logging_allowed)
{
ack_prepare_message(ERR_OK, mu);
}
return;
}
error_code err = _prepare_list->prepare(mu, status());
dassert (err == ERR_OK, "");
if (PS_POTENTIAL_SECONDARY == status())
{
dassert (mu->data.header.decree <= last_committed_decree() + _options.staleness_for_start_prepare_for_potential_secondary, "");
}
else
{
dassert (PS_SECONDARY == status(), "");
dassert (mu->data.header.decree <= last_committed_decree() + _options.staleness_for_commit, "");
}
// ack without logging
if (_options.prepare_ack_on_secondary_before_logging_allowed)
{
ack_prepare_message(err, mu);
}
// write log
dassert (mu->log_task() == nullptr, "");
mu->log_task() = _stub->_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
this,
std::bind(&replica::on_append_log_completed, this, mu, std::placeholders::_1, std::placeholders::_2),
gpid_to_hash(get_gpid())
);
dassert(mu->log_task() != nullptr, "");
}