Chiebot-Mirror
/
grpc
mirror of https://github.com/grpc/grpc.git
8
0
Fork 0
Code Issues Projects Releases Wiki Activity

priority LB: remove optimization for CONNECTING after config update (#30705)

Browse Source 
* priority LB: remove optimization for CONNECTING after config update

* fix build

* remove unnecessary layer of indirection
pull/30787/head
Mark D. Roth 2 years ago committed by GitHub
parent dffc20df69
commit c84c0434b3
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 46 additions and 138 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 176
      src/core/ext/filters/client_channel/lb_policy/priority/priority.cc

176
src/core/ext/filters/client_channel/lb_policy/priority/priority.cc
Unescape View File

@ -255,11 +255,6 @@ class PriorityLb : public LoadBalancingPolicy {
// the child is not in the current priority list.
uint32_t GetChildPriorityLocked(const std::string& child_name) const;
// Called when a child's connectivity state has changed.
// May propagate the update to the channel or trigger choosing a new
// priority.
void HandleChildConnectivityStateChangeLocked(ChildPriority* child);
// Deletes a child. Called when the child's deactivation timer fires.
void DeleteChild(ChildPriority* child);
@ -277,9 +272,11 @@ class PriorityLb : public LoadBalancingPolicy {
void ChoosePriorityLocked();
// Sets the specified priority as the current priority.
// Deactivates any children at lower priorities.
// Optionally deactivates any children at lower priorities.
// Returns the child's picker to the channel.
void SetCurrentPriorityLocked(uint32_t priority);
void SetCurrentPriorityLocked(int32_t priority,
bool deactivate_lower_priorities,
const char* reason);
const Duration child_failover_timeout_;
@ -299,10 +296,6 @@ class PriorityLb : public LoadBalancingPolicy {
std::map<std::string, OrphanablePtr<ChildPriority>> children_;
// The priority that is being used.
uint32_t current_priority_ = UINT32_MAX;
// Points to the current child from before the most recent update.
// We will continue to use this child until we decide which of the new
// children to use.
ChildPriority* current_child_from_before_update_ = nullptr;
};
//
@ -355,15 +348,6 @@ void PriorityLb::UpdateLocked(UpdateArgs args) {
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO, "[priority_lb %p] received update", this);
}
// Save current child.
if (current_priority_ != UINT32_MAX) {
const std::string& child_name = config_->priorities()[current_priority_];
auto* child = children_[child_name].get();
GPR_ASSERT(child != nullptr);
if (child->connectivity_state() == GRPC_CHANNEL_READY) {
current_child_from_before_update_ = children_[child_name].get();
}
}
// Update config.
config_ = std::move(args.config);
// Update args.
@ -400,71 +384,13 @@ uint32_t PriorityLb::GetChildPriorityLocked(
return UINT32_MAX;
}
void PriorityLb::HandleChildConnectivityStateChangeLocked(
ChildPriority* child) {
// If we're in the process of propagating an update from our parent to
// our children, ignore any updates that come from the children. We
// will instead choose a new priority once the update has been seen by
// all children. This ensures that we don't incorrectly do the wrong
// thing while state is inconsistent.
if (update_in_progress_) return;
// Special case for the child that was the current child before the
// most recent update.
if (child == current_child_from_before_update_) {
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO,
"[priority_lb %p] state update for current child from before "
"config update",
this);
}
if (child->connectivity_state() == GRPC_CHANNEL_READY ||
child->connectivity_state() == GRPC_CHANNEL_IDLE) {
// If it's still READY or IDLE, we stick with this child, so pass
// the new picker up to our parent.
channel_control_helper()->UpdateState(child->connectivity_state(),
child->connectivity_status(),
child->GetPicker());
} else {
// If it's no longer READY or IDLE, we should stop using it.
// We already started trying other priorities as a result of the
// update, but calling ChoosePriorityLocked() ensures that we will
// properly select between CONNECTING and TRANSIENT_FAILURE as the
// new state to report to our parent.
current_child_from_before_update_ = nullptr;
ChoosePriorityLocked();
}
return;
}
// Otherwise, find the child's priority.
uint32_t child_priority = GetChildPriorityLocked(child->name());
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO,
"[priority_lb %p] state update for priority %u, child %s, current "
"priority %u",
this, child_priority, child->name().c_str(), current_priority_);
}
// Unconditionally call ChoosePriorityLocked(). It should do the
// right thing based on the state of all children.
ChoosePriorityLocked();
}
void PriorityLb::DeleteChild(ChildPriority* child) {
// If this was the current child from before the most recent update,
// stop using it. We already started trying other priorities as a
// result of the update, but calling ChoosePriorityLocked() ensures that
// we will properly select between CONNECTING and TRANSIENT_FAILURE as the
// new state to report to our parent.
if (current_child_from_before_update_ == child) {
current_child_from_before_update_ = nullptr;
ChoosePriorityLocked();
}
children_.erase(child->name());
}
void PriorityLb::ChoosePriorityLocked() {
// If priority list is empty, report TF.
if (config_->priorities().empty()) {
current_child_from_before_update_ = nullptr;
absl::Status status =
absl::UnavailableError("priority policy has empty priority list");
channel_control_helper()->UpdateState(
@ -484,52 +410,30 @@ void PriorityLb::ChoosePriorityLocked() {
priority, child_name.c_str());
}
auto& child = children_[child_name];
// Create child if needed.
if (child == nullptr) {
// If we're not still using an old child from before the last
// update, report CONNECTING here.
// This is probably not strictly necessary, since the child should
// immediately report CONNECTING and cause us to report that state
// anyway, but we do this just in case the child fails to report
// state before UpdateLocked() returns.
if (current_child_from_before_update_ == nullptr) {
channel_control_helper()->UpdateState(
GRPC_CHANNEL_CONNECTING, absl::Status(),
absl::make_unique<QueuePicker>(Ref(DEBUG_LOCATION, "QueuePicker")));
}
current_priority_ = priority;
child = MakeOrphanable<ChildPriority>(
Ref(DEBUG_LOCATION, "ChildPriority"), child_name);
auto child_config = config_->children().find(child_name);
GPR_DEBUG_ASSERT(child_config != config_->children().end());
child->UpdateLocked(child_config->second.config,
child_config->second.ignore_reresolution_requests);
return;
}
// The child already exists.
} else {
// The child already exists. Reactivate if needed.
child->MaybeReactivateLocked();
// If the child is in state READY or IDLE, switch to it.
}
// Select this child if it is in states READY or IDLE.
if (child->connectivity_state() == GRPC_CHANNEL_READY ||
child->connectivity_state() == GRPC_CHANNEL_IDLE) {
SetCurrentPriorityLocked(priority);
SetCurrentPriorityLocked(
priority, /*deactivate_lower_priorities=*/true,
ConnectivityStateName(child->connectivity_state()));
return;
}
// Child is not READY or IDLE.
// If its failover timer is still pending, give it time to fire.
// Select this child if its failover timer is pending.
if (child->FailoverTimerPending()) {
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO,
"[priority_lb %p] priority %u, child %s: child still "
"attempting to connect, will wait",
this, priority, child_name.c_str());
}
current_priority_ = priority;
// If we're not still using an old child from before the last
// update, report CONNECTING here.
if (current_child_from_before_update_ == nullptr) {
channel_control_helper()->UpdateState(child->connectivity_state(),
child->connectivity_status(),
child->GetPicker());
}
SetCurrentPriorityLocked(priority, /*deactivate_lower_priorities=*/false,
"failover timer pending");
return;
}
// Child has been failing for a while. Move on to the next priority.
@ -560,42 +464,37 @@ void PriorityLb::ChoosePriorityLocked() {
auto& child = children_[child_name];
GPR_ASSERT(child != nullptr);
if (child->connectivity_state() == GRPC_CHANNEL_CONNECTING) {
channel_control_helper()->UpdateState(child->connectivity_state(),
child->connectivity_status(),
child->GetPicker());
SetCurrentPriorityLocked(priority, /*deactivate_lower_priorities=*/false,
"CONNECTING (pass 2)");
return;
}
}
// Did not find any child in CONNECTING, delegate to last child.
const std::string& child_name = config_->priorities().back();
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO,
"[priority_lb %p] no priority in CONNECTING, delegating to "
"lowest priority child %s",
this, child_name.c_str());
}
auto& child = children_[child_name];
GPR_ASSERT(child != nullptr);
channel_control_helper()->UpdateState(child->connectivity_state(),
child->connectivity_status(),
child->GetPicker());
SetCurrentPriorityLocked(config_->priorities().size() - 1,
/*deactivate_lower_priorities=*/false,
"no usable children");
}
void PriorityLb::SetCurrentPriorityLocked(uint32_t priority) {
void PriorityLb::SetCurrentPriorityLocked(int32_t priority,
bool deactivate_lower_priorities,
const char* reason) {
if (GRPC_TRACE_FLAG_ENABLED(grpc_lb_priority_trace)) {
gpr_log(GPR_INFO, "[priority_lb %p] selected priority %u, child %s", this,
priority, config_->priorities()[priority].c_str());
gpr_log(GPR_INFO,
"[priority_lb %p] selecting priority %u, child %s (%s, "
"deactivate_lower_priorities=%d)",
this, priority, config_->priorities()[priority].c_str(), reason,
deactivate_lower_priorities);
}
current_priority_ = priority;
current_child_from_before_update_ = nullptr;
// Deactivate lower priorities.
if (deactivate_lower_priorities) {
for (uint32_t p = priority + 1; p < config_->priorities().size(); ++p) {
const std::string& child_name = config_->priorities()[p];
auto it = children_.find(child_name);
if (it != children_.end()) it->second->MaybeDeactivateLocked();
}
// Update picker.
}
auto& child = children_[config_->priorities()[priority]];
GPR_ASSERT(child != nullptr);
channel_control_helper()->UpdateState(child->connectivity_state(),
child->connectivity_status(),
child->GetPicker());
@ -871,8 +770,17 @@ void PriorityLb::ChildPriority::OnConnectivityStateUpdateLocked(
seen_ready_or_idle_since_transient_failure_ = false;
failover_timer_.reset();
}
// Notify the parent policy.
priority_policy_->HandleChildConnectivityStateChangeLocked(this);
// Call the LB policy's ChoosePriorityLocked() to choose a priority to
// use based on the updated state of this child.
//
// Note that if we're in the process of propagating an update from our
// parent to our children, we skip this, because we don't want to
// choose a new priority based on inconsistent state. Instead, the
// policy will choose a new priority once the update has been seen by
// all children.
if (!priority_policy_->update_in_progress_) {
priority_policy_->ChoosePriorityLocked();
}
}
void PriorityLb::ChildPriority::MaybeDeactivateLocked() {

Write Preview
Loading…
Cancel
Save