icinga2/lib/icingadb/icingadb-worker.cpp
2026-04-02 16:37:57 +02:00

419 lines
17 KiB
C++

// SPDX-FileCopyrightText: 2025 Icinga GmbH <https://icinga.com>
// SPDX-License-Identifier: GPL-3.0-or-later
#include "icingadb/icingadb.hpp"
#include "base/logger.hpp"
#include <vector>
using namespace icinga;
icingadb::task_queue::PendingConfigItem::PendingConfigItem(const ConfigObject::Ptr& obj, uint32_t bits)
: Object{obj}, DirtyBits{bits & DirtyBitsAll}
{
}
icingadb::task_queue::PendingDependencyGroupStateItem::PendingDependencyGroupStateItem(const DependencyGroup::Ptr& depGroup)
: DepGroup{depGroup}
{
}
icingadb::task_queue::PendingDependencyEdgeItem::PendingDependencyEdgeItem(const DependencyGroup::Ptr& depGroup, const Checkable::Ptr& child)
: DepGroup{depGroup}, Child{child}
{
}
icingadb::task_queue::RelationsDeletionItem::RelationsDeletionItem(const String& id, const RelationsKeySet& relations)
: ID{id}, Relations{relations}
{
}
/**
* Background worker thread procedure for processing pending items.
*
* This function runs in a separate thread and continuously processes pending items that have been
* enqueued for Redis updates. It waits for new items to be added to the pending items container,
* and processes them one at a time, ensuring that the Redis connection is active and not overloaded
* with too many pending queries. The function also implements a delay mechanism to allow for potential
* additional changes to be merged into the same item before processing it.
*/
void IcingaDB::PendingItemsThreadProc()
{
namespace ch = std::chrono;
namespace queue = icingadb::task_queue;
// Limits the number of pending queries the Rcon can have at any given time to reduce the memory overhead to
// the absolute minimum necessary, since the size of the pending queue items is much smaller than the size
// of the actual Redis queries. Thus, this will slow down the worker thread a bit from generating too many
// Redis queries when the Redis connection is saturated.
constexpr std::size_t maxPendingQueries = 128;
// The minimum age an item must have before it can be processed.
constexpr ch::milliseconds minItemAge{300};
std::unique_lock lock(m_PendingItemsMutex);
// Wait until the initial config dump is done. IcingaDB::OnConnectedHandler will notify us once it's finished.
while (GetActive() && !m_ConfigDumpDone) m_PendingItemsCV.wait(lock);
auto& seqView = m_PendingItems.get<1>();
while (GetActive()) {
if (!m_PendingItems.empty() && m_RconWorker && m_RconWorker->IsConnected() && m_RconWorker->GetPendingQueryCount() < maxPendingQueries) {
auto now = ch::steady_clock::now();
auto it = seqView.begin();
if (auto age = now - it->EnqueueTime; minItemAge > age) {
m_PendingItemsCV.wait_for(lock, minItemAge - age);
} else {
auto itemToProcess = *it;
seqView.erase(it);
lock.unlock();
std::visit([this](auto &item) {
try {
ProcessQueueItem(item);
} catch (const std::exception& ex) {
Log(LogCritical, "IcingaDB")
<< "Exception while processing pending item of type '" << typeid(decltype(item)).name()
<< "': " << DiagnosticInformation(ex, GetActive());
}
}, itemToProcess.Item);
lock.lock();
}
} else {
// In case we don't receive any notification, we still want to wake up periodically on our own
// to check whether we can proceed (e.g. the Redis connection might have become available again and there
// was no activity on the pending items queue to trigger a notification). Thus, we use a timed wait here.
m_PendingItemsCV.wait_for(lock, 100ms);
}
}
}
/**
* Execute the pending configuration item.
*
* This function processes the pending configuration item by performing the necessary Redis operations based
* on the dirty bits set for the associated configuration object. It handles configuration deletions, updates,
* and state updates for checkable objects.
*
* @param item The queue item to process.
*/
void IcingaDB::ProcessQueueItem(const icingadb::task_queue::PendingConfigItem& item)
{
namespace queue = icingadb::task_queue;
ObjectLock olock(item.Object);
if (item.DirtyBits & queue::ConfigDelete) {
auto redisKeyPair = GetSyncableTypeRedisKeys(item.Object->GetReflectionType());
m_RconWorker->FireAndForgetQueries(
{
{"HDEL", redisKeyPair.ObjectKey, GetObjectIdentifier(item.Object)},
{"HDEL", redisKeyPair.ChecksumKey, GetObjectIdentifier(item.Object)},
{
"XADD",
"icinga:runtime",
"MAXLEN",
"~",
"1000000",
"*",
"redis_key",
redisKeyPair.ObjectKey,
"id",
GetObjectIdentifier(item.Object),
"runtime_type",
"delete"
}
}
);
}
if (item.DirtyBits & queue::ConfigUpdate) {
std::map<RedisConnection::QueryArg, RedisConnection::Query> hMSets;
std::vector<Dictionary::Ptr> runtimeUpdates;
CreateConfigUpdate(item.Object, GetSyncableTypeRedisKeys(item.Object->GetReflectionType()), hMSets, runtimeUpdates, true);
ExecuteRedisTransaction(m_RconWorker, hMSets, runtimeUpdates);
}
if (auto checkable = dynamic_pointer_cast<Checkable>(item.Object); checkable) {
if (item.DirtyBits & queue::FullState) {
UpdateState(checkable, item.DirtyBits);
}
if (item.DirtyBits & queue::NextUpdate) {
SendNextUpdate(checkable);
}
}
}
/**
* Execute the pending dependency group state item.
*
* This function processes the pending dependency group state item by updating the state of the
* dependency group in Redis. It selects any child checkable from the dependency group to initiate
* the state update, as all children share the same dependency group state.
*
* @param item The queue item to process.
*/
void IcingaDB::ProcessQueueItem(const icingadb::task_queue::PendingDependencyGroupStateItem& item) const
{
// For dependency group state updates, we don't actually care which child triggered the update,
// since all children share the same dependency group state. Thus, we can just pick any child to
// start the update from.
if (auto child = item.DepGroup->GetAnyChild(); child) {
UpdateDependenciesState(child, item.DepGroup);
}
}
/**
* Execute the pending dependency edge item.
*
* This function processes the pending dependency edge item and ensures that the necessary Redis
* operations are performed to register the child checkable as part of the dependency group.
*
* @param item The queue item to process.
*/
void IcingaDB::ProcessQueueItem(const icingadb::task_queue::PendingDependencyEdgeItem& item)
{
ObjectLock olock(item.Child);
std::vector<Dictionary::Ptr> runtimeUpdates;
std::map<RedisConnection::QueryArg, RedisConnection::Query> hMSets;
InsertCheckableDependencies(item.Child, hMSets, &runtimeUpdates, item.DepGroup);
ExecuteRedisTransaction(m_RconWorker, hMSets, runtimeUpdates);
}
/**
* Execute the pending relations deletion item.
*
* This function processes the pending relations deletion item by deleting the specified relations
* from Redis. It iterates over the map of Redis keys and deletes the relations associated with
* the given ID.
*
* @param item The queue item to process.
*/
void IcingaDB::ProcessQueueItem(const icingadb::task_queue::RelationsDeletionItem& item)
{
for (const auto& [configKey, checksumKey] : item.Relations) {
if (IsStateKey(configKey)) {
DeleteState(item.ID, configKey, checksumKey);
} else {
DeleteRelationship(item.ID, configKey, checksumKey);
}
}
}
/**
* Enqueue a configuration object for processing in the pending objects thread.
*
* @param object The configuration object to be enqueued for processing.
* @param bits The dirty bits indicating the type of changes to be processed for the object.
*/
void IcingaDB::EnqueueConfigObject(const ConfigObject::Ptr& object, uint32_t bits)
{
namespace queue = icingadb::task_queue;
if (!GetActive() || !m_RconWorker || !m_RconWorker->IsConnected()) {
return; // No need to enqueue anything if we're not connected.
}
{
std::lock_guard lock(m_PendingItemsMutex);
if (auto [it, inserted] = m_PendingItems.emplace(queue::PendingConfigItem{object, bits}); !inserted) {
m_PendingItems.modify(it, [bits](queue::PendingQueueItem& item) {
auto& configItem = std::get<queue::PendingConfigItem>(item.Item);
if (bits & queue::ConfigDelete) {
configItem.DirtyBits &= ~(queue::ConfigUpdate | queue::FullState);
} else if (bits & queue::ConfigUpdate) {
configItem.DirtyBits &= ~queue::ConfigDelete;
}
configItem.DirtyBits |= bits & queue::DirtyBitsAll;
});
}
}
m_PendingItemsCV.notify_one();
}
void IcingaDB::EnqueueDependencyGroupStateUpdate(const DependencyGroup::Ptr& depGroup)
{
if (GetActive() && m_RconWorker && m_RconWorker->IsConnected()) {
{
std::lock_guard lock(m_PendingItemsMutex);
m_PendingItems.emplace(icingadb::task_queue::PendingDependencyGroupStateItem{depGroup});
}
m_PendingItemsCV.notify_one();
}
}
/**
* Enqueue the registration of a dependency child to a dependency group.
*
* This function adds a pending item to the queue for processing the registration of a child checkable
* to a dependency group. If there is no active Redis connection available, this function is a no-op.
*
* @param depGroup The dependency group to which the child is being registered.
* @param child The child checkable being registered to the dependency group.
*/
void IcingaDB::EnqueueDependencyChildRegistered(const DependencyGroup::Ptr& depGroup, const Checkable::Ptr& child)
{
if (GetActive() && m_RconWorker && m_RconWorker->IsConnected()) {
{
std::lock_guard lock(m_PendingItemsMutex);
m_PendingItems.emplace(icingadb::task_queue::PendingDependencyEdgeItem{depGroup, child});
}
m_PendingItemsCV.notify_one();
}
}
/**
* Enqueue the removal of a dependency child from a dependency group.
*
* This function handles the removal of a child checkable from a dependency group by first checking if there
* are any pending registration items for the same child and dependency group. If such an item exists, it is
* removed from the pending items queue, effectively canceling the registration. If there is also a pending
* dependency group state update triggered by the same child, it is either removed or updated to use a different
* child if the group is not being removed entirely. If no pending registration exists, the function proceeds
* to enqueue the necessary deletions in Redis for the dependencies and related nodes and edges.
*
* @param depGroup The dependency group from which the child is being removed.
* @param dependencies The list of dependencies associated with the child being removed.
* @param removeGroup A flag indicating whether the entire dependency group should be removed.
*/
void IcingaDB::EnqueueDependencyChildRemoved(
const DependencyGroup::Ptr& depGroup,
const std::vector<Dependency::Ptr>& dependencies,
bool removeGroup
)
{
namespace queue = icingadb::task_queue;
if (dependencies.empty() || !GetActive() || !m_RconWorker || !m_RconWorker->IsConnected()) {
return; // No need to enqueue anything if we're not connected or there are no dependencies.
}
Checkable::Ptr child(dependencies.front()->GetChild());
bool cancelledRegistration = false;
{
std::lock_guard lock(m_PendingItemsMutex);
if (m_PendingItems.erase(std::make_pair(depGroup.get(), child.get())) > 0) {
cancelledRegistration = true;
if (removeGroup) {
// If we're removing the entire group registration, we can also drop any pending dependency group
// state update triggered previously as it should no longer have any children left.
m_PendingItems.erase(depGroup.get());
}
}
}
if (!child->HasAnyDependencies()) {
// If the child Checkable has no parent and reverse dependencies, we can safely remove the dependency node.
// This might be a no-op in some cases (e.g. if the child's only dependency was the one that we just canceled
// above), but since we can't reliably determine whether the node exists in Redis or not, we just enqueue the
// deletion anyway.
EnqueueRelationsDeletion(GetObjectIdentifier(child), {{CONFIG_REDIS_KEY_PREFIX "dependency:node", ""}});
}
if (cancelledRegistration && depGroup->GetIcingaDBIdentifier().IsEmpty()) {
// If we had a pending registration that we just canceled above, and the dependency group has no
// IcingaDB identifier yet, then there's no need to proceed with any deletions, as the dependency
// group was never serialized to Redis in the first place.
return;
}
if (depGroup->GetIcingaDBIdentifier().IsEmpty()) {
// An empty IcingaDB identifier indicates that the worker thread has just picked up the registration of the
// first child (removed from the pending items queue) but hasn't yet entered the InsertCheckableDependencies()
// function to actually fill in the IcingaDB identifier. Thus, we need to generate and set it here to ensure
// that the relation deletions below use the correct identifier.
if (depGroup->IsRedundancyGroup()) {
// Keep this with IcingaDB::InsertCheckableDependencies in sync!
depGroup->SetIcingaDBIdentifier(HashValue(new Array{m_EnvironmentId, depGroup->GetCompositeKey()}));
} else {
// This will set the IcingaDB identifier of the dependency group as a side effect.
(void)GetDependencyEdgeStateId(depGroup, dependencies.front());
}
}
std::set<Checkable*> detachedParents;
for (const auto& dependency : dependencies) {
const auto& parent(dependency->GetParent());
if (auto [_, inserted] = detachedParents.insert(dependency->GetParent().get()); inserted) {
String edgeId;
if (depGroup->IsRedundancyGroup()) {
// If the redundancy group has no members left, it's going to be removed as well, so we need to
// delete dependency edges from that group to the parent Checkables.
if (removeGroup) {
EnqueueRelationsDeletion(
GetDependencyEdgeStateId(depGroup, dependency),
{
{CONFIG_REDIS_KEY_PREFIX "dependency:edge", ""},
{CONFIG_REDIS_KEY_PREFIX "dependency:edge:state", ""},
}
);
}
// Remove the connection from the child Checkable to the redundancy group.
edgeId = HashValue(new Array{GetObjectIdentifier(child), depGroup->GetIcingaDBIdentifier()});
} else {
// Remove the edge between the parent and child Checkable linked through the removed dependency.
edgeId = HashValue(new Array{GetObjectIdentifier(child), GetObjectIdentifier(parent)});
}
EnqueueRelationsDeletion(edgeId, {{CONFIG_REDIS_KEY_PREFIX "dependency:edge", ""}});
// The total_children and affects_children columns might now have different outcome, so update the parent
// Checkable as well. The grandparent Checkable may still have wrong numbers of total children, though it's
// not worth traversing the whole tree way up and sending config updates for each one of them, as the next
// Redis config dump is going to fix it anyway.
EnqueueConfigObject(parent, queue::ConfigUpdate);
if (!parent->HasAnyDependencies()) {
// If the parent Checkable isn't part of any other dependency chain anymore, drop its dependency node entry.
EnqueueRelationsDeletion(GetObjectIdentifier(parent), {{CONFIG_REDIS_KEY_PREFIX "dependency:node", ""}});
}
}
}
if (removeGroup && depGroup->IsRedundancyGroup()) {
EnqueueRelationsDeletion(
depGroup->GetIcingaDBIdentifier(),
{
{CONFIG_REDIS_KEY_PREFIX "dependency:node", ""},
{CONFIG_REDIS_KEY_PREFIX "redundancygroup", ""},
{CONFIG_REDIS_KEY_PREFIX "redundancygroup:state", ""},
{CONFIG_REDIS_KEY_PREFIX "dependency:edge:state", ""}
}
);
} else if (removeGroup) {
// Note: The Icinga DB identifier of a non-redundant dependency group is used as the edge state ID
// and shared by all of its dependency objects. See also SerializeDependencyEdgeState() for details.
EnqueueRelationsDeletion(depGroup->GetIcingaDBIdentifier(), {{CONFIG_REDIS_KEY_PREFIX "dependency:edge:state", ""}});
}
}
/**
* Enqueue a relation deletion for processing in the pending objects thread.
*
* This function adds a relation deletion item to the set of pending items to be processed by the
* pending items worker thread. The relation deletion item contains the ID of the relation to be
* deleted and a map of Redis keys from which to delete the relation. If the relation deletion item
* is already in the set, it updates the deletion keys accordingly.
*
* @param id The ID of the relation to be deleted.
* @param relations A map of Redis keys from which to delete the relation.
*/
void IcingaDB::EnqueueRelationsDeletion(const String& id, icingadb::task_queue::RelationsDeletionItem::RelationsKeySet relations)
{
namespace queue = icingadb::task_queue;
if (!GetActive() || !m_RconWorker || !m_RconWorker->IsConnected()) {
return; // No need to enqueue anything if we're not connected.
}
{
std::lock_guard lock(m_PendingItemsMutex);
if (auto [it, inserted] = m_PendingItems.emplace(queue::RelationsDeletionItem{id, relations}); !inserted) {
m_PendingItems.modify(it, [&relations](queue::PendingQueueItem& val) {
auto& item = std::get<queue::RelationsDeletionItem>(val.Item);
item.Relations.merge(std::move(relations));
});
}
}
m_PendingItemsCV.notify_one();
}