[Enhancement] limit persistent index compaction by disk (StarRocks#36681

) Why I'm doing: In current implementation, we doesn't control the compaction concurrency on one disk, which will cause compaction unbalanced between disks, and some disk's IO cost will be too high. What I'm doing: Limit the disk compaction concurrency by config pindex_major_compaction_limit_per_disk . Refactor persistent index compaction scheduler code. Signed-off-by: luohaha <18810541851@163.com>
willWang8023 · Dec 25, 2023 · a44147f · a44147f
1 parent 832d7b0
commit a44147f
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Showing 8 changed files with 289 additions and 37 deletions.
diff --git a/be/src/common/config.h b/be/src/common/config.h
@@ -1042,8 +1042,10 @@ CONF_Bool(enable_pindex_minor_compaction, "true");
 // if l2 num is larger than this, stop doing async compaction,
 // add this config to prevent l2 grow too large.
 CONF_mInt64(max_allow_pindex_l2_num, "5");
-// control the background compaction threads
-CONF_mInt64(pindex_major_compaction_num_threads, "0");
+// Number of max major compaction threads
+CONF_mInt32(pindex_major_compaction_num_threads, "0");
+// Limit of major compaction per disk.
+CONF_mInt32(pindex_major_compaction_limit_per_disk, "2");
 // control the persistent index schedule compaction interval
 CONF_mInt64(pindex_major_compaction_schedule_interval_seconds, "15");
 // control the local persistent index in shared_data gc/evict interval

diff --git a/be/src/http/action/update_config_action.cpp b/be/src/http/action/update_config_action.cpp
@@ -117,7 +117,8 @@ Status UpdateConfigAction::update_config(const std::string& name, const std::str
             PersistentIndexCompactionManager* mgr =
                     StorageEngine::instance()->update_manager()->get_pindex_compaction_mgr();
             if (mgr != nullptr) {
-                (void)mgr->update_max_threads(config::pindex_major_compaction_num_threads);
+                const int max_pk_index_compaction_thread_cnt = std::max(1, config::pindex_major_compaction_num_threads);
+                (void)mgr->update_max_threads(max_pk_index_compaction_thread_cnt);
             }
         });
         _config_callback.emplace("update_memory_limit_percent", [&]() {

diff --git a/be/src/storage/olap_server.cpp b/be/src/storage/olap_server.cpp
@@ -397,9 +397,11 @@ void* StorageEngine::_pk_index_major_compaction_thread_callback(void* arg) {
     ProfilerRegisterThread();
 #endif
     while (!_bg_worker_stopped.load(std::memory_order_consume)) {
-        SLEEP_IN_BG_WORKER(config::pindex_major_compaction_schedule_interval_seconds);
+        SLEEP_IN_BG_WORKER(1);
         // schedule persistent index compaction
-        _update_manager->get_pindex_compaction_mgr()->schedule();
+        _update_manager->get_pindex_compaction_mgr()->schedule([&]() {
+            return StorageEngine::instance()->tablet_manager()->pick_tablets_to_do_pk_index_major_compaction();
+        });
     }
 
     return nullptr;

diff --git a/be/src/storage/persistent_index.cpp b/be/src/storage/persistent_index.cpp
@@ -4842,8 +4842,8 @@ StatusOr<EditVersion> PersistentIndex::_major_compaction_impl(
     return new_l2_version;
 }
 
-static void modify_l2_versions(const std::vector<EditVersion>& input_l2_versions, const EditVersion& output_l2_version,
-                               PersistentIndexMetaPB& index_meta) {
+void PersistentIndex::modify_l2_versions(const std::vector<EditVersion>& input_l2_versions,
+                                         const EditVersion& output_l2_version, PersistentIndexMetaPB& index_meta) {
     // delete input l2 versions, and add output l2 version
     std::vector<EditVersion> new_l2_versions;
     std::vector<bool> new_l2_version_merged;

diff --git a/be/src/storage/persistent_index.h b/be/src/storage/persistent_index.h
@@ -751,6 +751,9 @@ class PersistentIndex {
 
     void reset_cancel_major_compaction();
 
+    static void modify_l2_versions(const std::vector<EditVersion>& input_l2_versions,
+                                   const EditVersion& output_l2_version, PersistentIndexMetaPB& index_meta);
+
 protected:
     Status _delete_expired_index_file(const EditVersion& l0_version, const EditVersion& l1_version,
                                       const EditVersionWithMerge& min_l2_version);

diff --git a/be/src/storage/persistent_index_compaction_manager.cpp b/be/src/storage/persistent_index_compaction_manager.cpp
@@ -29,7 +29,7 @@ PersistentIndexCompactionManager::~PersistentIndexCompactionManager() {
 }
 
 Status PersistentIndexCompactionManager::init() {
-    int max_pk_index_compaction_thread_cnt =
+    const int max_pk_index_compaction_thread_cnt =
             config::pindex_major_compaction_num_threads > 0
                     ? config::pindex_major_compaction_num_threads
                     : std::max((size_t)1, StorageEngine::instance()->get_store_num() * 2);
@@ -50,56 +50,71 @@ class PkIndexMajorCompactionTask : public Runnable {
 
     void run() override {
         WARN_IF_ERROR(_tablet->updates()->pk_index_major_compaction(), "Failed to run PkIndexMajorCompactionTask");
-        _mgr->unmark_running(_tablet->tablet_id());
+        _mgr->unmark_running(_tablet.get());
     }
 
 private:
     TabletSharedPtr _tablet;
     PersistentIndexCompactionManager* _mgr;
 };
 
-void PersistentIndexCompactionManager::schedule() {
-    if (_too_many_tasks()) {
-        // too many running tasks, stop schedule
-        LOG(WARNING) << "PersistentIndex compaction schedule failed, too many running tasks";
-        return;
-    }
-    std::vector<TabletAndScore> pick_tablets =
-            StorageEngine::instance()->tablet_manager()->pick_tablets_to_do_pk_index_major_compaction();
-    for (auto& tablet_score : pick_tablets) {
-        const int64_t tablet_id = tablet_score.first->tablet_id();
-        if (_need_skip(tablet_id)) {
+void PersistentIndexCompactionManager::schedule(const std::function<std::vector<TabletAndScore>()>& pick_algo) {
+    update_ready_tablet_queue(pick_algo);
+    for (auto it = _ready_tablets_queue.begin(); it != _ready_tablets_queue.end();) {
+        auto& tablet_score = *it;
+        if (is_running(tablet_score.first.get())) {
+            // remove this tablet because it is already running
+            it = _ready_tablets_queue.erase(it);
+            continue;
+        }
+        if (disk_limit(tablet_score.first.get())) {
+            // skip it, may re-run it next round.
+            ++it;
             continue;
         }
-        mark_running(tablet_id);
+        mark_running(tablet_score.first.get());
         std::shared_ptr<Runnable> r = std::make_shared<PkIndexMajorCompactionTask>(tablet_score.first, this);
         auto st = _worker_thread_pool->submit(std::move(r));
         if (!st.ok()) {
-            unmark_running(tablet_id);
+            // Resource busy, break and quit
+            unmark_running(tablet_score.first.get());
             LOG(ERROR) << strings::Substitute("submit pk index compaction task failed: $0", st.to_string());
             break;
         }
+        it = _ready_tablets_queue.erase(it);
+    }
+}
+
+void PersistentIndexCompactionManager::update_ready_tablet_queue(
+        const std::function<std::vector<TabletAndScore>()>& pick_algo) {
+    size_t current_time = time(nullptr);
+    if (current_time - _last_schedule_time > config::pindex_major_compaction_schedule_interval_seconds) {
+        // need re-schedule
+        _ready_tablets_queue = pick_algo();
+        _last_schedule_time = current_time;
     }
 }
 
-void PersistentIndexCompactionManager::mark_running(int64_t tablet_id) {
+void PersistentIndexCompactionManager::mark_running(Tablet* tablet) {
     std::lock_guard<std::mutex> guard(_mutex);
-    _running_tablets.insert(tablet_id);
+    _running_tablets.insert(tablet->tablet_id());
+    _data_dir_to_task_num_map[tablet->data_dir()]++;
 }
 
-void PersistentIndexCompactionManager::unmark_running(int64_t tablet_id) {
+void PersistentIndexCompactionManager::unmark_running(Tablet* tablet) {
     std::lock_guard<std::mutex> guard(_mutex);
-    _running_tablets.erase(tablet_id);
+    _running_tablets.erase(tablet->tablet_id());
+    _data_dir_to_task_num_map[tablet->data_dir()]--;
 }
 
-bool PersistentIndexCompactionManager::_too_many_tasks() {
+bool PersistentIndexCompactionManager::is_running(Tablet* tablet) {
     std::lock_guard<std::mutex> guard(_mutex);
-    return _running_tablets.size() > MAX_RUNNING_TABLETS;
+    return _running_tablets.count(tablet->tablet_id()) > 0;
 }
 
-bool PersistentIndexCompactionManager::_need_skip(int64_t tablet_id) {
+bool PersistentIndexCompactionManager::disk_limit(Tablet* tablet) {
     std::lock_guard<std::mutex> guard(_mutex);
-    return _running_tablets.count(tablet_id) > 0;
+    return _data_dir_to_task_num_map[tablet->data_dir()] >= std::max(1, config::pindex_major_compaction_limit_per_disk);
 }
 
 Status PersistentIndexCompactionManager::update_max_threads(int max_threads) {

diff --git a/be/src/storage/persistent_index_compaction_manager.h b/be/src/storage/persistent_index_compaction_manager.h
@@ -21,6 +21,7 @@
 
 #include "storage/olap_common.h"
 #include "storage/tablet.h"
+#include "storage/tablet_manager.h"
 
 namespace starrocks {
 
@@ -31,19 +32,28 @@ class PersistentIndexCompactionManager {
     PersistentIndexCompactionManager() {}
     ~PersistentIndexCompactionManager();
     Status init();
-    void schedule();
-    void mark_running(int64_t tablet_id);
-    void unmark_running(int64_t tablet_id);
+    void schedule(const std::function<std::vector<TabletAndScore>()>& pick_algo);
+    // Mark tablet is running and increase disk concurrency
+    void mark_running(Tablet* tablet);
+    // Mark tablet is no running and decrease disk concurrency
+    void unmark_running(Tablet* tablet);
+    // change the thread pool thread count
     Status update_max_threads(int max_threads);
+    // Call pick algo function, and refresh ready tablet queue
+    void update_ready_tablet_queue(const std::function<std::vector<TabletAndScore>()>& pick_algo);
+    // Is tablet in running state
+    bool is_running(Tablet* tablet);
+    // Is tablet's disk out of concurrency limit
+    bool disk_limit(Tablet* tablet);
 
 private:
-    bool _too_many_tasks();
-    bool _need_skip(int64_t tablet_id);
-    static const uint32_t MAX_RUNNING_TABLETS = 1000;
-
     std::mutex _mutex;
+    // Sorted by prority
+    std::vector<TabletAndScore> _ready_tablets_queue;
     std::unordered_set<int64_t> _running_tablets;
     std::unique_ptr<ThreadPool> _worker_thread_pool;
+    std::unordered_map<DataDir*, uint64_t> _data_dir_to_task_num_map;
+    size_t _last_schedule_time = 0;
 };
 
 } // namespace starrocks