afbb940a05
Summary: - GC changed to evaluate old records w.r.t. the oldest transaction's id AND snapshot, as opposed to only id - MVCC hints exp+aborted race condition prevented - minor MVCC refactors and cleanups - minor Transaction refactors and cleanups Reviewers: buda, dgleich Reviewed By: buda, dgleich Subscribers: dtomicevic, pullbot Differential Revision: https://phabricator.memgraph.io/D434
38 lines
935 B
C++
38 lines
935 B
C++
#pragma once
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#include "mvcc/record.hpp"
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/**
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* @brief - Empty class which inherits from mvcc:Record.
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*/
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class Prop : public mvcc::Record<Prop> {};
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/**
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* @brief - Class which inherits from mvcc::Record and takes an atomic variable
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* to count number of destructor calls (to test if the record is actually
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* deleted).
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*/
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class DestrCountRec : public mvcc::Record<DestrCountRec> {
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public:
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DestrCountRec(std::atomic<int> &count) : count_(count) {}
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~DestrCountRec() { ++count_; }
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private:
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std::atomic<int> &count_;
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};
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// helper function for creating a GC snapshot
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// if given a nullptr it makes a GC snapshot like there
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// are no active transactions
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auto GcSnapshot(tx::Engine &engine, tx::Transaction *t) {
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if (t != nullptr) {
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tx::Snapshot gc_snap = t->snapshot();
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gc_snap.insert(t->id_);
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return gc_snap;
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} else {
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tx::Snapshot gc_snap;
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gc_snap.insert(engine.Count() + 1);
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return gc_snap;
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}
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}
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