From 4e924043ae0d93600a5bf16c2c1c694e53516100 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B8rgen=20Edelbo?= Date: Tue, 22 Nov 2022 12:49:22 +0100 Subject: [PATCH 1/3] Fix corruption of freelist during compaction --- src/realm/group_writer.cpp | 40 +++++++++++++++++++------------------- test/test_compaction.cpp | 4 ++-- 2 files changed, 22 insertions(+), 22 deletions(-) diff --git a/src/realm/group_writer.cpp b/src/realm/group_writer.cpp index 3306436278b..d21dc51738c 100644 --- a/src/realm/group_writer.cpp +++ b/src/realm/group_writer.cpp @@ -766,6 +766,26 @@ ref_type GroupWriter::write_group() top.set(Group::s_free_version_ndx, from_ref(free_versions_ref)); // Throws top.set(Group::s_version_ndx, RefOrTagged::make_tagged(m_current_version)); // Throws + if (m_evacuation_limit == 0 && m_backoff == 0) { + size_t used_space = m_logical_size - m_free_space_size; + // Compacting files smaller than 1 Mb is not worth the effort. Arbitrary chosen value. + static constexpr size_t minimal_compaction_size = 0x100000; + // If we make the file too small, there is a big chance it will grow immediately afterwards + static constexpr size_t minimal_evac_limit = 0x10000; + if (m_logical_size >= minimal_compaction_size && m_free_space_size - m_locked_space_size > 2 * used_space) { + // Clean up potential + auto limit = util::round_up_to_page_size(used_space + used_space / 2 + m_locked_space_size); + m_evacuation_limit = std::max(minimal_evac_limit, limit); + // From now on, we will only allocate below this limit + // Save the limit in the file + while (top.size() <= Group::s_evacuation_point_ndx) { + top.add(0); + } + top.set(Group::s_evacuation_point_ndx, RefOrTagged::make_tagged(m_evacuation_limit)); + // std::cout << "Evacuation point = " << std::hex << m_evacuation_limit << std::dec << std::endl; + } + } + // Get final sizes size_t top_byte_size = top.get_byte_size(); ref_type end_ref = top_ref + top_byte_size; @@ -791,26 +811,6 @@ ref_type GroupWriter::write_group() m_free_lengths.set(reserve_ndx, value_9); // Throws m_free_space_size += rest; - if (m_evacuation_limit == 0 && m_backoff == 0) { - size_t used_space = m_logical_size - m_free_space_size; - // Compacting files smaller than 1 Mb is not worth the effort. Arbitrary chosen value. - static constexpr size_t minimal_compaction_size = 0x100000; - // If we make the file too small, there is a big chance it will grow immediately afterwards - static constexpr size_t minimal_evac_limit = 0x10000; - if (m_logical_size >= minimal_compaction_size && m_free_space_size - m_locked_space_size > 2 * used_space) { - // Clean up potential - auto limit = util::round_up_to_page_size(used_space + used_space / 2 + m_locked_space_size); - m_evacuation_limit = std::max(minimal_evac_limit, limit); - // From now on, we will only allocate below this limit - // Save the limit in the file - while (top.size() <= Group::s_evacuation_point_ndx) { - top.add(0); - } - top.set(Group::s_evacuation_point_ndx, RefOrTagged::make_tagged(m_evacuation_limit)); - // std::cout << "Evacuation point = " << std::hex << m_evacuation_limit << std::dec << std::endl; - } - } - #if REALM_ALLOC_DEBUG std::cout << " Final Freelist:" << std::endl; for (size_t j = 0; j < m_free_positions.size(); ++j) { diff --git a/test/test_compaction.cpp b/test/test_compaction.cpp index 11e65aa544b..edf889ed218 100644 --- a/test/test_compaction.cpp +++ b/test/test_compaction.cpp @@ -59,11 +59,11 @@ TEST(Compaction_WhileGrowing) for (int i = 0; i < 5000; ++i) { w[i] = '0' + (i % 64); } - int num = (REALM_MAX_BPNODE_SIZE == 1000) ? 1490 : 1400; + int num = (REALM_MAX_BPNODE_SIZE == 1000) ? 1400 : 1300; tr->promote_to_write(); CHECK(db->get_evacuation_stage() == DB::EvacStage::idle); for (int j = 0; j < num; ++j) { - table1->create_object().set(col_bin1, BinaryData(w, 400)); + table1->create_object().set(col_bin1, BinaryData(w, 450)); table2->create_object().set(col_bin2, BinaryData(w, 200)); if (j % 10 == 0) { tr->commit_and_continue_as_read(); From c7c800bded69f43f10edbbf3040e1423a944a9c4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B8rgen=20Edelbo?= Date: Tue, 22 Nov 2022 12:52:51 +0100 Subject: [PATCH 2/3] Update release notes --- CHANGELOG.md | 1 + 1 file changed, 1 insertion(+) diff --git a/CHANGELOG.md b/CHANGELOG.md index 66abafda777..981b5f2c00e 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -7,6 +7,7 @@ ### Fixed * ([#????](https://github.com/realm/realm-core/issues/????), since v?.?.?) * Fixed wrong assertion on query error that could result in a crash. ([#6038](https://github.com/realm/realm-core/issues/6038), since v11.7.0) +* Freelist may be corrupted if compaction was initiated ([#6054](https://github.com/realm/realm-core/pull/6054), since v13.0.0) ### Breaking changes * Updated `logger_factory` in SyncClientConfig to return a `shared_ptr` instead of a `unique_ptr` ([PR #5980](https://github.com/realm/realm-core/pull/5980)) From 4edd414e6e836dd27d4abc5f63a021a3e7470773 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B8rgen=20Edelbo?= Date: Tue, 22 Nov 2022 13:34:18 +0100 Subject: [PATCH 3/3] Try to fix test on arm64 --- test/test_compaction.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/test/test_compaction.cpp b/test/test_compaction.cpp index edf889ed218..ccc35fcd677 100644 --- a/test/test_compaction.cpp +++ b/test/test_compaction.cpp @@ -113,7 +113,7 @@ TEST(Compaction_WhileGrowing) tr->commit_and_continue_as_read(); // Now there should be room for compaction - auto n = 20; // Ensure that test will end + auto n = 50; // Ensure that test will end do { tr->promote_to_write(); tr->commit_and_continue_as_read();