Remove the manual batch size estimation logic (`SizeEstimate()` method and `size_estimate` member) from `CDBBatch`.
Size is now determined solely by the `ApproximateSize()` method introduced in the previous commit, which delegates to the native LevelDB function.
The manual calculation is no longer necessary as LevelDB now provides this functionality directly, and the previous commit verified that the native function's results matched the manual estimation.
Assertions comparing the two methods are removed from `txdb.cpp`.
Co-authored-by: Wladimir J. van der Laan <laanwj@protonmail.com>
Serialized batch size can be queried via the underlying LevelDB implementation calling the native `leveldb::WriteBatch::ApproximateSize()`.
The previous manual calculation was added in e66dbde6d1 as part of https://github.com/bitcoin/bitcoin/pull/10195. At that time (April 2017), the version of LevelDB used by Bitcoin Core (and even the latest source) lacked a native function for this. LevelDB added this capability in 69e2bd224b, merged later that year.
The old manual estimation method (`SizeEstimate()`) is kept temporarily in this commit, and assertions are added in `txdb.cpp` to verify its results against `ApproximateSize()` during batch writes. This ensures the native function behaves as expected before removing the manual calculation in the subsequent commit.
The initialization of the manual `size_estimate` in `CDBBatch::Clear()` is corrected from `0` to `kHeader` (LevelDB's fixed batch header size).
This aligns the manual estimate with LevelDB's actual size immediately after clearing, fixing discrepancies that would otherwise be caught by tests in the next commit (e.g., `coins_tests`, `validation_chainstatemanager_tests`).
Historically, the headers have been bumped some time after a file has
been touched. Do it now to avoid having to touch them again in the
future for that reason.
-BEGIN VERIFY SCRIPT-
sed -i --regexp-extended 's;( 20[0-2][0-9])(-20[0-2][0-9])? The Bitcoin Core developers;\1-present The Bitcoin Core developers;g' $( git show --pretty="" --name-only HEAD~1 )
-END VERIFY SCRIPT-
In theory this commit should only touch the span.h header, because
std::span can implicilty convert into Span in most places, if needed.
However, at least when using the clang compiler, there are some
false-positive lifetimebound warnings and some implicit conversions can
not be resolved.
Thus, this refactoring commit also changed the affected places to
replace Span with std::span.
The default max file size for LevelDB is 2 MiB, which results in the
LevelDB compaction code generating ~4 disk cache flushes per second when
syncing with the Bitcoin network.
These disk cache flushes are triggered by fdatasync() syscall issued by the
LevelDB compaction code when reaching the max file size.
If the database is on a HDD this flush rate brings the whole system to a
crawl.
It also results in very slow throughput since 2 MiB * 4 flushes per second
is about 8 MiB / second max throughput, while even an old HDD can pull
100 - 200 MiB / second streaming throughput.
Increase the max file size for LevelDB to 32 MiB instead so the flush rate
drops significantly and the system no longer gets so sluggish.
The new max file size value chosen is a compromise between the one that
works best for HDD and SSD performance, as determined by benchmarks done by
various people.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
Since CharCast is no longer needed in the header, move it to the
implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Make it a static function in dbwrapper.cpp, since it is not used
elsewhere and when left in the header, would expose a leveldb type.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Hide the leveldb::Iterator member variable with a pimpl in order not to
expose it directly in the header.
Also, move CDBWrapper::NewIterator to the dbwrapper implementation to
use the pimpl for CDBIterator initialziation.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Hide the leveldb::WriteBatch member variable with a pimpl in order not
to expose it directly in the header.
Also move CDBBatch::Clear to the dbwrapper implementation to use the new
impl_batch.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Keep the generic serialization in the header, while moving
leveldb-specifics to the implementation file.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
Wrap leveldb::DestroyDB in a helper function without exposing
leveldb-specifics.
Also, add missing optional include.
The context of this commit is an effort to decouple the dbwrapper header
file from leveldb includes. To this end, the includes are moved to the
dbwrapper implementation file. This is done as part of the kernel
project to reduce the number of required includes for users of the
kernel.
The fs.* files are already part of the libbitcoin_util library. With the
introduction of the fs_helpers.* it makes sense to move fs.* into the
util/ directory as well.
Add DBParams and DBOptions structs to remove ArgsManager uses from dbwrapper.
To reduce size of this commit, this moves references to gArgs variable out of
dbwrapper.cpp to calling code in txdb.cpp. But these moves are temporary. The
gArgs references in txdb.cpp are moved out to calling code in init.cpp in later
commits.
This commit does not change behavior.
This method hasn't been used since the txindex migration code has been
removed (PR #22626, commit fa20f815a9).
Co-authored-by: furszy <matiasfurszyfer@protonmail.com>
These methods haven't been used since the chainstate db cache has been
switched from per-tx to per-txout model years ago (PR #10195, commit
d342424301).
fa29272459 Remove redundant MakeUCharSpan wrappers (MarcoFalke)
faf4aa2f47 Remove CDataStream::Init in favor of C++11 member initialization (MarcoFalke)
fada14b948 Treat CDataStream bytes as uint8_t (MarcoFalke)
fa8bdb048e refactor: Drop CDataStream constructors in favor of one taking a Span of bytes (MarcoFalke)
faa96f841f Remove unused CDataStream methods (MarcoFalke)
Pull request description:
Using `uint8_t` for raw bytes has a style benefit:
* The signedness is clear from reading the code, as it does not depend on the architecture
Other clean-ups in this pull include:
* Remove unused methods
* Constructor is simplified with `Span`
* Remove `Init()` member in favor of C++11 member initialization
ACKs for top commit:
laanwj:
code review ACK fa29272459
theStack:
ACK fa29272459🍾
Tree-SHA512: 931ee28bd99843d7e894b48e90e1187ffb0278677c267044b3c0c255069d9bbd9298ab2e539b1002a30b543d240450eaec718ef4ee95a7fd4be0a295e926343f
