void replica::on_append_log_completed(mutation_ptr& mu, error_code err, size_t size)
{
check_hashed_access();
ddebug( "%s: mutation %s on_append_log_completed, err = %s", name(), mu->name(), err.to_string());
if (err == ERR_OK)
{
mu->set_logged();
}
// skip old mutations
if (mu->data.header.ballot < get_ballot() || status() == PS_INACTIVE)
{
return;
}
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);
}
if (!_options.prepare_ack_on_secondary_before_logging_allowed)
{
ack_prepare_message(err, mu);
}
break;
case PS_ERROR:
break;
default:
dassert (false, "");
break;
}
}
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_append_log_completed(mutation_ptr& mu, uint32_t err, uint32_t size)
{
check_hashed_access();
ddebug( "%s: mutation %s on_append_log_completed, err = %u", name(), mu->name(), err);
if (err == ERR_SUCCESS)
{
mu->set_logged();
}
// skip old mutations
if (mu->data.header.ballot < get_ballot() || status() == PS_INACTIVE)
{
return;
}
switch (status())
{
case PS_PRIMARY:
if (err == ERR_SUCCESS)
{
do_possible_commit_on_primary(mu);
}
else
{
handle_local_failure(err);
}
break;
case PS_SECONDARY:
case PS_POTENTIAL_SECONDARY:
if (err != ERR_SUCCESS)
{
handle_local_failure(err);
}
ack_prepare_message(err, mu);
break;
case PS_ERROR:
break;
default:
dassert (false, "");
break;
}
}
void replica::execute_mutation(mutation_ptr& mu)
{
dassert (nullptr != _app, "");
int err = ERR_SUCCESS;
switch (status())
{
case PS_INACTIVE:
if (_app->last_committed_decree() + 1 == mu->data.header.decree)
err = _app->write_internal(mu, false);
break;
case PS_PRIMARY:
case PS_SECONDARY:
{
dassert (_app->last_committed_decree() + 1 == mu->data.header.decree, "");
bool ack_client = (status() == PS_PRIMARY);
if (ack_client)
{
if (mu->client_request == nullptr)
ack_client = false;
else if (mu->client_request->header().from_address.ip == 0)
ack_client = false;
}
err = _app->write_internal(mu, ack_client);
}
break;
case PS_POTENTIAL_SECONDARY:
if (LearningSucceeded == _potential_secondary_states.learning_status)
{
if (mu->data.header.decree == _app->last_committed_decree() + 1)
{
err = _app->write_internal(mu, false);
}
else
{
dassert (mu->data.header.decree <= _app->last_committed_decree(), "");
}
}
else
{
// drop mutations as learning will catch up
ddebug("%s: mutation %s skipped coz learing buffer overflow", name(), mu->name());
}
break;
case PS_ERROR:
break;
}
ddebug("TwoPhaseCommit, %s: mutation %s committed, err = %x", name(), mu->name(), err);
if (err != ERR_SUCCESS)
{
handle_local_failure(err);
}
}
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::execute_mutation(mutation_ptr& mu)
{
dinfo("%s: execute mutation %s: request_count = %u",
name(),
mu->name(),
static_cast<int>(mu->client_requests.size())
);
error_code err = ERR_OK;
decree d = mu->data.header.decree;
switch (status())
{
case partition_status::PS_INACTIVE:
if (_app->last_committed_decree() + 1 == d)
{
err = _app->write_internal(mu);
}
else
{
ddebug(
"%s: mutation %s commit to %s skipped, app.last_committed_decree = %" PRId64,
name(), mu->name(),
enum_to_string(status()),
_app->last_committed_decree()
);
}
break;
case partition_status::PS_PRIMARY:
{
check_state_completeness();
dassert(_app->last_committed_decree() + 1 == d, "");
err = _app->write_internal(mu);
}
break;
case partition_status::PS_SECONDARY:
if (!_secondary_states.checkpoint_is_running)
{
check_state_completeness();
dassert (_app->last_committed_decree() + 1 == d, "");
err = _app->write_internal(mu);
}
else
{
ddebug(
"%s: mutation %s commit to %s skipped, app.last_committed_decree = %" PRId64,
name(), mu->name(),
enum_to_string(status()),
_app->last_committed_decree()
);
// make sure private log saves the state
// catch-up will be done later after checkpoint task is fininished
dassert(_private_log != nullptr, "");
}
break;
case partition_status::PS_POTENTIAL_SECONDARY:
if (_potential_secondary_states.learning_status == learner_status::LearningSucceeded ||
_potential_secondary_states.learning_status == learner_status::LearningWithPrepareTransient)
{
dassert(_app->last_committed_decree() + 1 == d, "");
err = _app->write_internal(mu);
}
else
{
// prepare also happens with learner_status::LearningWithPrepare, in this case
// make sure private log saves the state,
// catch-up will be done later after the checkpoint task is finished
ddebug(
"%s: mutation %s commit to %s skipped, app.last_committed_decree = %" PRId64,
name(), mu->name(),
enum_to_string(status()),
_app->last_committed_decree()
);
}
break;
case partition_status::PS_ERROR:
break;
}
ddebug("TwoPhaseCommit, %s: mutation %s committed, err = %s", name(), mu->name(), err.to_string());
_counter_commit_latency.set(dsn_now_ns() - mu->create_ts_ns());
if (err != ERR_OK)
{
handle_local_failure(err);
}
if (status() == partition_status::PS_PRIMARY)
{
mutation_ptr next = _primary_states.write_queue.check_possible_work(
static_cast<int>(_prepare_list->max_decree() - d)
);
if (next)
{
init_prepare(next);
}
}
}
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::on_checkpoint_completed(error_code err)
{
check_hashed_access();
// closing or wrong timing or no need operate
if (PS_SECONDARY != status() || err == ERR_WRONG_TIMING || err == ERR_NO_NEED_OPERATE)
{
_secondary_states.checkpoint_is_running = false;
return;
}
// handle failure
if (err != ERR_OK)
{
// done checkpointing
_secondary_states.checkpoint_is_running = false;
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, "");
err = _app->write_internal(mu);
if (ERR_OK != err)
{
_secondary_states.checkpoint_is_running = false;
handle_local_failure(err);
return;
}
}
// everything is ok now, done checkpointing
_secondary_states.checkpoint_is_running = false;
}
// missed ones need to be loaded via private logs
else
{
tasking::enqueue(
&_secondary_states.catchup_with_private_log_task,
LPC_CATCHUP_WITH_PRIVATE_LOGS,
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_is_running = false;
}
}
void replica::on_append_log_completed(mutation_ptr& mu, error_code err, size_t size)
{
check_hashed_access();
ddebug( "%s: mutation %s on_append_log_completed, err = %s", name(), mu->name(), err.to_string());
if (err == ERR_OK)
{
mu->set_logged();
}
// skip old mutations
if (mu->data.header.ballot < get_ballot() || status() == PS_INACTIVE)
{
return;
}
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);
}
ack_prepare_message(err, mu);
break;
case PS_ERROR:
break;
default:
dassert (false, "");
break;
}
// mutation log failure, propagted to all replicas
if (err != ERR_OK)
{
_stub->handle_log_failure(err);
}
// write local private log if necessary
else if (_private_log && status() != PS_ERROR)
{
_private_log->append(mu,
LPC_WRITE_REPLICATION_LOG,
this,
[this](error_code err, size_t size)
{
if (err != ERR_OK)
{
handle_local_failure(err);
}
},
gpid_to_hash(get_gpid())
);
}
}
void replica::init_prepare(mutation_ptr& mu)
{
dassert (PS_PRIMARY == status(), "");
error_code err = ERR_SUCCESS;
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);
}
if (mu->data.header.decree > _prepare_list->max_decree() && _prepare_list->count() >= _options.staleness_for_commit)
{
err = ERR_CAPACITY_EXCEEDED;
goto ErrOut;
}
dassert (mu->data.header.decree > last_committed_decree(), "");
// local prepare without log
err = _prepare_list->prepare(mu, PS_PRIMARY);
if (err != ERR_SUCCESS)
{
goto ErrOut;
}
ddebug("%s: mutation %s init_prepare", name(), mu->name());
//
// TODO: bounded staleness on secondaries
//
dassert (mu->data.header.decree <= last_committed_decree() + _options.staleness_for_commit, "");
// remote prepare
dassert (mu->remote_tasks().size() == 0, "");
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);
// 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())
);
if (nullptr == mu->log_task())
{
err = ERR_FILE_OPERATION_FAILED;
handle_local_failure(err);
goto ErrOut;
}
return;
ErrOut:
response_client_message(mu->client_request, err);
return;
}
void replica::on_prepare(message_ptr& request)
{
check_hashed_access();
replica_configuration rconfig;
unmarshall(request, rconfig);
mutation_ptr mu = mutation::read_from(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())
{
update_local_configuration(rconfig);
}
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(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_SUCCESS, 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_prepared())
{
ack_prepare_message(ERR_SUCCESS, mu);
}
return;
}
int err = _prepare_list->prepare(mu, status());
dassert (err == ERR_SUCCESS, "");
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, "");
}
// 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())
);
if (nullptr == mu->log_task())
{
err = ERR_FILE_OPERATION_FAILED;
ack_prepare_message(err, mu);
handle_local_failure(err);
}
}