DatabaseCon.cpp

#include <xrpld/core/DatabaseCon.h>
#include <xrpld/core/SociDB.h>
 
#include <xrpl/basics/Log.h>
#include <xrpl/basics/contract.h>
 
#include <boost/algorithm/string.hpp>
#include <boost/format.hpp>
 
#include <memory>
#include <unordered_map>
 
namespace xrpl {
 
class CheckpointersCollection
{
    std::uintptr_t nextId_{0};
    // Mutex protects the CheckpointersCollection
    std::mutex mutex_;
    // Each checkpointer is given a unique id. All the checkpointers that are
    // part of a DatabaseCon are part of this collection. When the DatabaseCon
    // is destroyed, its checkpointer is removed from the collection
    std::unordered_map<std::uintptr_t, std::shared_ptr<Checkpointer>> checkpointers_;
 
public:
    std::shared_ptr<Checkpointer>
    fromId(std::uintptr_t id)
    {
        std::lock_guard l{mutex_};
        auto it = checkpointers_.find(id);
        if (it != checkpointers_.end())
            return it->second;
        return {};
    }
 
    void
    erase(std::uintptr_t id)
    {
        std::lock_guard lock{mutex_};
        checkpointers_.erase(id);
    }
 
    std::shared_ptr<Checkpointer>
    create(std::shared_ptr<soci::session> const& session, JobQueue& jobQueue, Logs& logs)
    {
        std::lock_guard lock{mutex_};
        auto const id = nextId_++;
        auto const r = makeCheckpointer(id, session, jobQueue, logs);
        checkpointers_[id] = r;
        return r;
    }
};
 
CheckpointersCollection checkpointers;
 
std::shared_ptr<Checkpointer>
checkpointerFromId(std::uintptr_t id)
{
    return checkpointers.fromId(id);
}
 
DatabaseCon::~DatabaseCon()
{
    if (checkpointer_)
    {
        checkpointers.erase(checkpointer_->id());
 
        std::weak_ptr<Checkpointer> wk(checkpointer_);
        checkpointer_.reset();
 
        // The references to our Checkpointer held by 'checkpointer_' and
        // 'checkpointers' have been removed, so if the use count is nonzero, a
        // checkpoint is currently in progress. Wait for it to end, otherwise
        // creating a new DatabaseCon to the same database may fail due to the
        // database being locked by our (now old) Checkpointer.
        while (wk.use_count())
        {
            std::this_thread::sleep_for(std::chrono::milliseconds(100));
        }
    }
}
 
DatabaseCon::Setup
setup_DatabaseCon(Config const& c, std::optional<beast::Journal> j)
{
    DatabaseCon::Setup setup;
 
    setup.startUp = c.START_UP;
    setup.standAlone = c.standalone();
    setup.dataDir = c.legacy("database_path");
    if (!setup.standAlone && setup.dataDir.empty())
    {
        Throw<std::runtime_error>("database_path must be set.");
    }
 
    if (!setup.globalPragma)
    {
        setup.globalPragma = [&c, &j]() {
            auto const& sqlite = c.section("sqlite");
            auto result = std::make_unique<std::vector<std::string>>();
            result->reserve(3);
 
            // defaults
            std::string safety_level;
            std::string journal_mode = "wal";
            std::string synchronous = "normal";
            std::string temp_store = "file";
            bool showRiskWarning = false;
 
            if (set(safety_level, "safety_level", sqlite))
            {
                if (boost::iequals(safety_level, "low"))
                {
                    // low safety defaults
                    journal_mode = "memory";
                    synchronous = "off";
                    temp_store = "memory";
                    showRiskWarning = true;
                }
                else if (!boost::iequals(safety_level, "high"))
                {
                    Throw<std::runtime_error>("Invalid safety_level value: " + safety_level);
                }
            }
 
            {
                // #journal_mode Valid values : delete, truncate, persist,
                // memory, wal, off
                if (set(journal_mode, "journal_mode", sqlite) && !safety_level.empty())
                {
                    Throw<std::runtime_error>(
                        "Configuration file may not define both "
                        "\"safety_level\" and \"journal_mode\"");
                }
                bool higherRisk = boost::iequals(journal_mode, "memory") || boost::iequals(journal_mode, "off");
                showRiskWarning = showRiskWarning || higherRisk;
                if (higherRisk || boost::iequals(journal_mode, "delete") || boost::iequals(journal_mode, "truncate") ||
                    boost::iequals(journal_mode, "persist") || boost::iequals(journal_mode, "wal"))
                {
                    result->emplace_back(boost::str(boost::format(CommonDBPragmaJournal) % journal_mode));
                }
                else
                {
                    Throw<std::runtime_error>("Invalid journal_mode value: " + journal_mode);
                }
            }
 
            {
                // #synchronous Valid values : off, normal, full, extra
                if (set(synchronous, "synchronous", sqlite) && !safety_level.empty())
                {
                    Throw<std::runtime_error>(
                        "Configuration file may not define both "
                        "\"safety_level\" and \"synchronous\"");
                }
                bool higherRisk = boost::iequals(synchronous, "off");
                showRiskWarning = showRiskWarning || higherRisk;
                if (higherRisk || boost::iequals(synchronous, "normal") || boost::iequals(synchronous, "full") ||
                    boost::iequals(synchronous, "extra"))
                {
                    result->emplace_back(boost::str(boost::format(CommonDBPragmaSync) % synchronous));
                }
                else
                {
                    Throw<std::runtime_error>("Invalid synchronous value: " + synchronous);
                }
            }
 
            {
                // #temp_store Valid values : default, file, memory
                if (set(temp_store, "temp_store", sqlite) && !safety_level.empty())
                {
                    Throw<std::runtime_error>(
                        "Configuration file may not define both "
                        "\"safety_level\" and \"temp_store\"");
                }
                bool higherRisk = boost::iequals(temp_store, "memory");
                showRiskWarning = showRiskWarning || higherRisk;
                if (higherRisk || boost::iequals(temp_store, "default") || boost::iequals(temp_store, "file"))
                {
                    result->emplace_back(boost::str(boost::format(CommonDBPragmaTemp) % temp_store));
                }
                else
                {
                    Throw<std::runtime_error>("Invalid temp_store value: " + temp_store);
                }
            }
 
            if (showRiskWarning && j && c.LEDGER_HISTORY > SQLITE_TUNING_CUTOFF)
            {
                JLOG(j->warn()) << "reducing the data integrity guarantees from the "
                                   "default [sqlite] behavior is not recommended for "
                                   "nodes storing large amounts of history, because of the "
                                   "difficulty inherent in rebuilding corrupted data.";
            }
            XRPL_ASSERT(result->size() == 3, "xrpl::setup_DatabaseCon::globalPragma : result size is 3");
            return result;
        }();
    }
    setup.useGlobalPragma = true;
 
    auto setPragma = [](std::string& pragma, std::string const& key, int64_t value) {
        pragma = "PRAGMA " + key + "=" + std::to_string(value) + ";";
    };
 
    // Lgr Pragma
    setPragma(setup.lgrPragma[0], "journal_size_limit", 1582080);
 
    // TX Pragma
    int64_t page_size = 4096;
    int64_t journal_size_limit = 1582080;
    if (c.exists("sqlite"))
    {
        auto& s = c.section("sqlite");
        set(journal_size_limit, "journal_size_limit", s);
        set(page_size, "page_size", s);
        if (page_size < 512 || page_size > 65536)
            Throw<std::runtime_error>("Invalid page_size. Must be between 512 and 65536.");
 
        if (page_size & (page_size - 1))
            Throw<std::runtime_error>("Invalid page_size. Must be a power of 2.");
    }
 
    setPragma(setup.txPragma[0], "page_size", page_size);
    setPragma(setup.txPragma[1], "journal_size_limit", journal_size_limit);
    setPragma(setup.txPragma[2], "max_page_count", 4294967294);
    setPragma(setup.txPragma[3], "mmap_size", 17179869184);
 
    return setup;
}
 
std::unique_ptr<std::vector<std::string> const> DatabaseCon::Setup::globalPragma;
 
void
DatabaseCon::setupCheckpointing(JobQueue* q, Logs& l)
{
    if (!q)
        Throw<std::logic_error>("No JobQueue");
    checkpointer_ = checkpointers.create(session_, *q, l);
}
 
}  // namespace xrpl