memgraph/tests/unit/mvcc.cpp
florijan c4327b26f4 Extract tx::SingleNodeEngine from tx::MasterEngine
Summary:
No logic changes, just split `tx::MasterEngine` into
`tx::SingleNodeEngine` and `tx::MasterEngine`. This gives better
responsibility separation and is more appropriate now there is no
Start/Shutdown.

Reviewers: dgleich, teon.banek, buda

Reviewed By: dgleich, teon.banek

Subscribers: pullbot

Differential Revision: https://phabricator.memgraph.io/D1099
2018-01-11 15:44:42 +01:00

75 lines
2.0 KiB
C++

#include <vector>
#include "gtest/gtest.h"
#include "mvcc/record.hpp"
#include "mvcc/version.hpp"
#include "mvcc/version_list.hpp"
#include "threading/sync/lock_timeout_exception.hpp"
#include "transactions/engine_single_node.hpp"
#include "transactions/transaction.hpp"
#include "mvcc_gc_common.hpp"
TEST(MVCC, Deadlock) {
tx::SingleNodeEngine engine;
auto t0 = engine.Begin();
mvcc::VersionList<Prop> version_list1(*t0, 0);
mvcc::VersionList<Prop> version_list2(*t0, 1);
engine.Commit(*t0);
auto t1 = engine.Begin();
auto t2 = engine.Begin();
version_list1.update(*t1);
version_list2.update(*t2);
EXPECT_THROW(version_list1.update(*t2), LockTimeoutException);
}
// TODO Gleich: move this test to mvcc_gc???
// check that we don't delete records when we re-link
TEST(MVCC, UpdateDontDelete) {
std::atomic<int> count{0};
{
tx::SingleNodeEngine engine;
auto t1 = engine.Begin();
mvcc::VersionList<DestrCountRec> version_list(*t1, 0, count);
engine.Commit(*t1);
auto t2 = engine.Begin();
version_list.update(*t2);
engine.Abort(*t2);
EXPECT_EQ(count, 0);
auto t3 = engine.Begin();
// Update re-links the node and shouldn't clear it yet.
version_list.update(*t3);
EXPECT_EQ(count, 0);
// TODO Gleich: why don't we also test that remove doesn't delete?
engine.Commit(*t3);
}
EXPECT_EQ(count, 3);
}
// Check that we get the oldest record.
TEST(MVCC, Oldest) {
tx::SingleNodeEngine engine;
auto t1 = engine.Begin();
mvcc::VersionList<Prop> version_list(*t1, 0);
auto first = version_list.Oldest();
EXPECT_NE(first, nullptr);
// TODO Gleich: no need to do 10 checks of the same thing
for (int i = 0; i < 10; ++i) {
engine.Advance(t1->id_);
version_list.update(*t1);
EXPECT_EQ(version_list.Oldest(), first);
}
// TODO Gleich: what about remove?
// TODO Gleich: here it might make sense to write a concurrent test
// since these ops rely heavily on linkage atomicity?
}
// TODO Gleich: perhaps some concurrent VersionList::find tests?