A recent change (4cb80b7ddc) to DBImpl::DeleteObsoleteFiles
unlocked DBImpl::mutex_ while deleting files to allow for
greater concurrency. This change improves on the prior in
a few areas:
1. The table is evicted from the table cache before unlocking
the mutex. This should only improve performance.
2. This implementation is slightly simpler, but at the cost of
a bit more memory usage.
3. A comment adding more detail as to why the mutex is being
unlocked and why it is safe to do so.
PiperOrigin-RevId: 253111645
mutex_ was already acquired before accessing DBImpl::versions_ in all
but one place: DBImpl::GetApproximateSizes. This change requires mutex_
to be held before accessing versions_.
PiperOrigin-RevId: 248390814
Currently, the benchmark used to assess leveldb changes lives in db/. The codebase also contains two benchmarks against other database engines in doc/bench/. Moving all the benchmarks in one place opens up the way for extracting common code.
PiperOrigin-RevId: 246737541
1) Convert iterator-based for loops to C++11 foreach loops.
2) Convert "void operator=" to "T& operator=".
3) Switch from copy operators from private to public deleted.
4) Switch from empty ctors / dtors to "= default" where appropriate.
PiperOrigin-RevId: 246679195
Use clang-format to correct formatting to be in agreement with the [Google C++ Style Guide](https://google.github.io/styleguide/cppguide.html). Doing this simplifies the process of accepting changes. Also fixed a few warnings flagged by clang-tidy.
PiperOrigin-RevId: 246350737
There were a few members which were identified to have been left
uninitialized in some constructors. These were very likely to
have been set before being used, otherwise the ASan tests would
have caught them, but still good practice to have them
initialized. This addresses some items reported in issue #668.
PiperOrigin-RevId: 243370145
Closesgoogle/leveldb#320
During compaction it was possible that records from a block b1=(l1,u1)
would be pushed down from level i to level i+1. If there is a block
b2=(l2,u2) at level i with k1 = user_key(u1) = user_key(l2) then
a subsequent search for k1 will yield the record l2 which has a smaller
sequence number than u1 because the sort order for records sorts
increasing by user key but decreaing by sequence number.
This change add a call to a new function AddBoundaryInputs to
SetupOtherInputs. AddBoundaryInputs searches for a block b2 matching the
criteria above and adds it to the set of files to be compacted. Whenever
AddBoundaryInputs is called it is important that the compaction fileset
in level i+1 (known as c->inputs_[1] in the code) be recomputed. Each
call to AddBoundaryInputs is followed by a call to GetOverlappingInputs.
SetupOtherInputs is called on both manual and automated compaction
passes. It is called for both level zero and for levels greater than 0.
The original change posted in https://github.com/google/leveldb/pull/339
has been modified to also include changed made by Chris Mumford<cmumford@google.com>
in 4b72cb14f8
1. Releasing snapshots during test cleanup to avoid
memory leak warnings.
2. Refactored test to use testutil.h to be in line
with other issue tests and to create the test
database in the correct temporary location.
3. Added copyright banner.
Otherwise, just minor formatting and limiting character
width to 80 characters.
Additionally the change was rebased on top of current master and
changes previously made to the Makefile were ported to the
CMakeLists.txt.
Testing Done:
A test program (issue320_test) was constructed that performs mutations
while snapshots are active. issue320_test fails without this bug fix
after 64k writes. It passes with this bug fix. It was run with 200M
writes and passed.
Unit tests were written for the new function that was added to the
code. Make test was run and seen to pass.
Signed-off-by: Richard Cole <richcole@amazon.com>
This change switches corruption_test, which previously used direct file
I/O to corrupt table files for open databases, to use InMemEnv. Using an
Env eliminates some platform dependencies thus simplifying the tests.
Also removed EnvWindowsTestHelper::RelaxFilePermissions(). This was
only added because the Windows Env opens files for exclusive access.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239305329
This CL moves default values for
leveldb::{Options,ReadOptions,WriteOptions} from constructors to member
declarations, and removes now-redundant comments stating the defaults.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239271242
This CL removes AtomicPointer from leveldb's port interface. Its usage is replaced with std::atomic<> from the C++11 standard library.
AtomicPointer was used to wrap flags, numbers, and pointers, so its instances are replaced with std::atomic<bool>, std::atomic<int>, std::atomic<size_t> and std::atomic<Node*>.
This CL does not revise the memory ordering. AtomicPointer's methods are replaced mechanically with their std::atomic equivalents, even when the underlying usage is incorrect. (Example: DBImpl::has_imm_ is written using release stores, even though it is always read using relaxed ordering.) Revising the memory ordering is left for future CLs.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=237865146
This change adds a native Windows port (port_windows.h) and a
Windows Env (WindowsEnv).
Note1: "small" is defined when including <Windows.h> so some
parameters were renamed to avoid conflict.
Note2: leveldb::Env defines the method: "DeleteFile" which is
also a constant defined when including <Windows.h>. The solution
was to ensure this macro is defined in env.h which forces
the function, when compiled, to be either DeleteFileA or
DeleteFileW when building for MBCS or UNICODE respectively.
This resolves#519 on GitHub.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=236364778
ssize_t is not standard C++. It is a POSIX extension. Therefore, it does
not belong in generic code.
This change tweaks the logic in DBIter to remove the need for signed
integers, so ssize_t can be replaced with size_t. The impacted method
and private member are renamed to better express their purpose.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=211471606
WriteBatchInternal has a method for efficiently concatenating two
WriteBatches. This commit exposes the method to the public API.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=208724311
* Omit SnapshotImpl::list_ when assert() isn't on
* Make SnapshotImpl::number_ const and set it in the constructor
* Make SnapshotImpl::number_ private and access it via a getter
* Rename SnapshotImpl::number_ to SnapshotImpl::sequence_number_
* Rename SnapshotList::list_ to SnapshotList::head_
* Wrap casting from Snapshot* to SnapshotImpl* in ToSnapshotImpl()
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194852828
After this CL, all classes with Mutex members should be covered by annotations. Exceptions are atomic members, which shouldn't need locking, and DBImpl members that cause errors when annotated, which will be tackled separately.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=190260865
This CL makes it easier to reason about thread safety by:
1) Adding Clang thread safety annotations according to comments.
2) Expanding a couple of variable names, without adding extra lines of code.
3) Adding const in a couple of places.
4) Replacing an always-non-null const pointer with a reference.
5) Fixing style warnings in the modified files.
This CL does not annotate the DBImpl members that claim to be protected
by the instance mutex, but are accessed without the mutex being held.
Those members (and their unprotected accesses) will be addressed in
future CLs.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=189354657
This CL removes unused headers included by util/testharness.h, adds
precise includes where the build breaks, and fixes style errors in the
edited files.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=189331061
External linkage is the default for function declarations in C++.
This also fixes ClangTidy errors generated by removing the "extern"
keyword as described above.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=188730416
