Summary:
This is a feature to sample data-block compressibility and and report them as stats. 1 in N (tunable) blocks is sampled for compressibility using two algorithms:
1. lz4 or snappy for fast compression
2. zstd or zlib for slow but higher compression.
The stats are reported to the caller as raw-bytes and compressed-bytes. The block continues to be compressed for storage using the specified CompressionType.
The db_bench_tool how has a command line option for specifying the sampling rate. It's default value is 0 (no sampling). To test the overhead for a certain value, users can compare the performance of db_bench_tool, varying the sampling rate. It is unlikely to have a noticeable impact for high values like 20.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4842
Differential Revision: D13629011
Pulled By: shobhitdayal
fbshipit-source-id: 14ca668bcab6499b2a1734edf848eb62a4f4fafa
Summary:
Our previous approach was to train one compression dictionary per compaction, using the first output SST to train a dictionary, and then applying it on subsequent SSTs in the same compaction. While this was great for minimizing CPU/memory/I/O overhead, it did not achieve good compression ratios in practice. In our most promising potential use case, moderate reductions in a dictionary's scope make a major difference on compression ratio.
So, this PR changes compression dictionary to be scoped per-SST. It accepts the tradeoff during table building to use more memory and CPU. Important changes include:
- The `BlockBasedTableBuilder` has a new state when dictionary compression is in-use: `kBuffered`. In that state it accumulates uncompressed data in-memory whenever `Add` is called.
- After accumulating target file size bytes or calling `BlockBasedTableBuilder::Finish`, a `BlockBasedTableBuilder` moves to the `kUnbuffered` state. The transition (`EnterUnbuffered()`) involves sampling the buffered data, training a dictionary, and compressing/writing out all buffered data. In the `kUnbuffered` state, a `BlockBasedTableBuilder` behaves the same as before -- blocks are compressed/written out as soon as they fill up.
- Samples are now whole uncompressed data blocks, except the final sample may be a partial data block so we don't breach the user's configured `max_dict_bytes` or `zstd_max_train_bytes`. The dictionary trainer is supposed to work better when we pass it real units of compression. Previously we were passing 64-byte KV samples which was not realistic.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4952
Differential Revision: D13967980
Pulled By: ajkr
fbshipit-source-id: 82bea6f7537e1529c7a1a4cdee84585f5949300f
Summary:
The current implementation hardcode the default options in different
places, which makes it impossible to support other environments (like
encrypted environment).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4839
Differential Revision: D13573578
Pulled By: sagar0
fbshipit-source-id: 76b58b4b758902798d10ff2f52d9f39abff015e7
Summary:
A user friendly sst file reader is useful when we want to access sst
files outside of RocksDB. For example, we can generate an sst file
with SstFileWriter and send it to other places, then use SstFileReader
to read the file and process the entries in other ways.
Also rename the original SstFileReader to SstFileDumper because of
name conflict, and seems SstFileDumper is more appropriate for tools.
TODO: there is only a very simple test now, because I want to get some feedback first.
If the changes look good, I will add more tests soon.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4717
Differential Revision: D13212686
Pulled By: ajkr
fbshipit-source-id: 737593383264c954b79e63edaf44aaae0d947e56
Summary:
Ran the following commands to recursively change all the files under RocksDB:
```
find . -type f -name "*.cc" -exec sed -i 's/ unique_ptr/ std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<unique_ptr/<std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/ shared_ptr/ std::shared_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<shared_ptr/<std::shared_ptr/g' {} +
```
Running `make format` updated some formatting on the files touched.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4638
Differential Revision: D12934992
Pulled By: sagar0
fbshipit-source-id: 45a15d23c230cdd64c08f9c0243e5183934338a8
Summary:
Since the number of range deletions are reported in
TableProperties, it is confusing to not report the number of merge
operands and point deletions as top-level properties; they are
accessible through the public API, but since they are not the "main"
properties, they do not appear in aggregated table properties, or the
string representation of table properties.
This change promotes those two property keys to
`rocksdb/table_properties.h`, adds corresponding uint64 members for
them, deprecates the old access methods `GetDeletedKeys()` and
`GetMergeOperands()` (though they are still usable for now), and removes
`InternalKeyPropertiesCollector`. The property key strings are the same
as before this change, so this should be able to read DBs written from older
versions (though I haven't tested this yet).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4594
Differential Revision: D12826893
Pulled By: abhimadan
fbshipit-source-id: 9e4e4fbdc5b0da161c89582566d184101ba8eb68
Summary:
We want to sample the file I/O issued by RocksDB and report the function calls. This requires us to include the file paths otherwise it's hard to tell what has been going on.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4039
Differential Revision: D8670178
Pulled By: riversand963
fbshipit-source-id: 97ee806d1c583a2983e28e213ee764dc6ac28f7a
Summary:
https://github.com/facebook/rocksdb/pull/3881 fixed a bug where PinnableSlice pin mmap files which could be deleted with background compaction. This is however a non-issue for ReadOnlyDB when there is no compaction running and max_open_files is -1. This patch reenables the pinning feature for that case.
Closes https://github.com/facebook/rocksdb/pull/4053
Differential Revision: D8662546
Pulled By: maysamyabandeh
fbshipit-source-id: 402962602eb0f644e17822748332999c3af029fd
Summary:
Currently it is not possible to change bloom filter config without restart the db, which is causing a lot of operational complexity for users.
This PR aims to make it possible to dynamically change bloom filter config.
Closes https://github.com/facebook/rocksdb/pull/3601
Differential Revision: D7253114
Pulled By: miasantreble
fbshipit-source-id: f22595437d3e0b86c95918c484502de2ceca120c
Summary:
- Switched all instances of SetMinPossibleForUserKey and SetMaxPossibleForUserKey in accordance to InternalKeyComparator's comparison logic
Closes https://github.com/facebook/rocksdb/pull/2868
Differential Revision: D5804152
Pulled By: axxufb
fbshipit-source-id: 80be35e04f2e8abc35cc64abe1fecb03af24e183
Summary:
- like other subcommands, reporting compression sizes should be specified with the `--command` CLI arg.
- also added `--compression_types` arg as it's useful to restrict the types of compression used, at least in my dictionary compression experiments.
Closes https://github.com/facebook/rocksdb/pull/2706
Differential Revision: D5589520
Pulled By: ajkr
fbshipit-source-id: 305bb4ebcc95eecc8a85523cd3b1050619c9ddc5
Summary:
Right now, if direct I/O is enabled, prefetching the last 512KB cannot be applied, except compaction inputs or readahead is enabled for iterators. This can create a lot of I/O for HDD cases. To solve the problem, the 512KB is prefetched in block based table if direct I/O is enabled. The prefetched buffer is passed in totegher with random access file reader, so that we try to read from the buffer before reading from the file. This can be extended in the future to support flexible user iterator readahead too.
Closes https://github.com/facebook/rocksdb/pull/2708
Differential Revision: D5593091
Pulled By: siying
fbshipit-source-id: ee36ff6d8af11c312a2622272b21957a7b5c81e7
Summary:
We need a tool to check any sst file corruption in the db.
It will check all the sst files in current version and read all the blocks (data, meta, index) with checksum verification. If any verification fails, the function will return non-OK status.
Closes https://github.com/facebook/rocksdb/pull/2498
Differential Revision: D5324269
Pulled By: lightmark
fbshipit-source-id: 6f8a272008b722402a772acfc804524c9d1a483b
Summary:
Replace dynamic_cast<> so that users can choose to build with RTTI off, so that they can save several bytes per object, and get tiny more memory available.
Some nontrivial changes:
1. Add Comparator::GetRootComparator() to get around the internal comparator hack
2. Add the two experiemental functions to DB
3. Add TableFactory::GetOptionString() to avoid unnecessary casting to get the option string
4. Since 3 is done, move the parsing option functions for table factory to table factory files too, to be symmetric.
Closes https://github.com/facebook/rocksdb/pull/2645
Differential Revision: D5502723
Pulled By: siying
fbshipit-source-id: fd13cec5601cf68a554d87bfcf056f2ffa5fbf7c
Summary:
This reverts the previous commit 1d7048c598, which broke the build.
Did a `git revert 1d7048c`.
Closes https://github.com/facebook/rocksdb/pull/2627
Differential Revision: D5476473
Pulled By: sagar0
fbshipit-source-id: 4756ff5c0dfc88c17eceb00e02c36176de728d06
Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.
Reviewed By: igorsugak
Differential Revision: D5454343
fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2
Summary:
We've got some DBs where iterators return Status with message "Corruption: block checksum mismatch" all the time. That's not very informative. It would be much easier to investigate if the error message contained the file name - then we would know e.g. how old the corrupted file is, which would be very useful for finding the root cause. This PR adds file name, offset and other stuff to some block corruption-related status messages.
It doesn't improve all the error messages, just a few that were easy to improve. I'm mostly interested in "block checksum mismatch" and "Bad table magic number" since they're the only corruption errors that I've ever seen in the wild.
Closes https://github.com/facebook/rocksdb/pull/2507
Differential Revision: D5345702
Pulled By: al13n321
fbshipit-source-id: fc8023d43f1935ad927cef1b9c55481ab3cb1339
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
Summary:
Add the flag --prefix to the sst_dump tool
This flag is similar to, and exclusive from, the --from flag.
--prefix=0x00FF will return all rows prefixed with 0x00FF.
The --to flag may also be specified and will work as expected.
These changes were used to help in debugging the power cycle corruption issue and theses changes were tested by scanning through a udb.
Closes https://github.com/facebook/rocksdb/pull/1984
Differential Revision: D4691814
Pulled By: reidHoruff
fbshipit-source-id: 027f261
Summary:
?tion
Add flags in db_bench to test with block cache mid-point insertion.
Also update sst_dump to dump total block sizes of each type. I find it
useful to look at these test db stats and I don't know if we have them
elsewhere.
Closes https://github.com/facebook/rocksdb/pull/1706
Differential Revision: D4355812
Pulled By: yiwu-arbug
fbshipit-source-id: 3e4a348
Summary:
Include a dump of user_collected_properties in sst_dump
Closes https://github.com/facebook/rocksdb/pull/1668
Differential Revision: D4325078
Pulled By: IslamAbdelRahman
fbshipit-source-id: 226b6d6
Summary:
enhancing sst_dump to be able to parse internal key
Closes https://github.com/facebook/rocksdb/pull/1482
Differential Revision: D4154175
Pulled By: siying
fbshipit-source-id: b0e28b1
Summary:
ZSTD 1.0.0 is coming. We can finally add a support of ZSTD without worrying about compatibility.
Still keep ZSTDNotFinal for compatibility reason.
Test Plan: Run all tests. Run db_bench with ZSTD version with RocksDB built with ZSTD 1.0 and older.
Reviewers: andrewkr, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: cyan, igor, IslamAbdelRahman, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D63141
Summary: There's no reference to ImmutableCFOptions elsewhere in /include/rocksdb. ImmutableCFOptions was introduced in this commit (5665e5e285) but later its reference in /include/rocksdb/table.h is removed.
Test Plan:
make all check
Reviewers: IslamAbdelRahman, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: yhchiang, andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D63177
* Added new statistics and refactored to allow ioptions to be passed around as required to access environment and statistics pointers (and, as a convenient side effect, info_log pointer).
* Prevent incrementing compression counter when compression is turned off in options.
* Prevent incrementing compression counter when compression is turned off in options.
* Added two more supported compression types to test code in db_test.cc
* Prevent incrementing compression counter when compression is turned off in options.
* Added new StatsLevel that excludes compression timing.
* Fixed casting error in coding.h
* Fixed CompressionStatsTest for new StatsLevel.
* Removed unused variable that was breaking the Linux build
Summary:
A couple of notes from the diff:
- The namespace block I added at the top of table_properties_collector.cc was in reaction to an issue i was having with PutVarint64 and reusing the "val" string. I'm not sure this is the cleanest way of doing this, but abstracting this out at least results in the correct behavior.
- I chose "rocksdb.merge.operands" as the property name. I am open to suggestions for better names.
- The change to sst_dump_tool.cc seems a bit inelegant to me. Is there a better way to do the if-else block?
Test Plan:
I added a test case in table_properties_collector_test.cc. It adds two merge operands and checks to make sure that both of them are reflected by GetMergeOperands. It also checks to make sure the wasPropertyPresent bool is properly set in the method.
Running both of these tests should pass:
./table_properties_collector_test
./sst_dump_test
Reviewers: IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D58119
Summary:
This is needed so that rocksdb users can add more
commands to the included ldb tool by adding more custom
commands.
Test Plan: make -j ldb
Reviewers: sdong, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D57243
Summary:
This adds a new metablock containing a shared dictionary that is used
to compress all data blocks in the SST file. The size of the shared dictionary
is configurable in CompressionOptions and defaults to 0. It's currently only
used for zlib/lz4/lz4hc, but the block will be stored in the SST regardless of
the compression type if the user chooses a nonzero dictionary size.
During compaction, computes the dictionary by randomly sampling the first
output file in each subcompaction. It pre-computes the intervals to sample
by assuming the output file will have the maximum allowable length. In case
the file is smaller, some of the pre-computed sampling intervals can be beyond
end-of-file, in which case we skip over those samples and the dictionary will
be a bit smaller. After the dictionary is generated using the first file in a
subcompaction, it is loaded into the compression library before writing each
block in each subsequent file of that subcompaction.
On the read path, gets the dictionary from the metablock, if it exists. Then,
loads that dictionary into the compression library before reading each block.
Test Plan: new unit test
Reviewers: yhchiang, IslamAbdelRahman, cyan, sdong
Reviewed By: sdong
Subscribers: andrewkr, yoshinorim, kradhakrishnan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52287
Comparable with Snappy on comp ratio.
Implemented using Windows API, does not require external package.
Avaiable since Windows 8 and server 2012.
Use -DXPRESS=1 with CMake to enable.
Summary:
Current Message
```
sst_dump [--command=check|scan|none|raw] [--verify_checksum] --file=data_dir_OR_sst_file [--output_hex] [--input_key_hex] [--from=<user_key>] [--to=<user_key>] [--read_num=NUM] [--show_properties] [--show_compression_sizes] [--show_compression_sizes [--set_block_size=<block_size>]]
```
New message
```
sst_dump --file=<data_dir_OR_sst_file> [--command=check|scan|raw]
--file=<data_dir_OR_sst_file>
Path to SST file or directory containing SST files
--command=check|scan|raw
check: Iterate over entries in files but dont print anything except if an error is encounterd (default command)
scan: Iterate over entries in files and print them to screen
raw: Dump all the table contents to <file_name>_dump.txt
--output_hex
Can be combined with scan command to print the keys and values in Hex
--from=<user_key>
Key to start reading from when executing check|scan
--to=<user_key>
Key to stop reading at when executing check|scan
--read_num=<num>
Maximum number of entries to read when executing check|scan
--verify_checksum
Verify file checksum when executing check|scan
--input_key_hex
Can be combined with --from and --to to indicate that these values are encoded in Hex
--show_properties
Print table properties after iterating over the file
--show_compression_sizes
Independent command that will recreate the SST file using 16K block size with different
compressions and report the size of the file using such compression
--set_block_size=<block_size>
Can be combined with --show_compression_sizes to set the block size that will be used
when trying different compression algorithms
```
Test Plan: none
Reviewers: yhchiang, andrewkr, kradhakrishnan, yiwu, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56325
Summary:
Added the column family name to the properties block. This property
is omitted only if the property is unavailable, such as when RepairDB()
writes SST files.
In a next diff, I will change RepairDB to use this new property for
deciding to which column family an existing SST file belongs. If this
property is missing, it will add it to the "unknown" column family (same
as its existing behavior).
Test Plan:
New unit test:
$ ./db_table_properties_test --gtest_filter=DBTablePropertiesTest.GetColumnFamilyNameProperty
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D55605
Summary:
Undefined Behavior Sanitizer (ubsan) is //a good thing// which will help us to find sneaky bugs with low cost. Please see http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/ for more details and official GCC documentation for more context: https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.html.
Changes itself are quite simple and pretty much imitating whatever is implemented for ASan.
Hooking the UBsan validation build to Sandcastle is a separate step and will be dealt as separate diff because code is in internal repository.
Test Plan: Make sure that that there no regressions when it comes to builds and test pass rate.
Reviewers: leveldb, sdong, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56049
Summary:
util/testutil.h doesn't seem to be used in tools/sst_dump_tool_imp.h. Remove it.
Also move some other include to tools/sst_dump_tool.cc instead.
Test Plan: Build with GCC, CLANG and with GCC 4.81 and 4.9.
Reviewers: yuslepukhin, yhchiang, rven, anthony, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52791
Summary:
When Get() or NewIterator() trigger file loads, skip caching the filter block if
(1) optimize_filters_for_hits is set and (2) the file is on the bottommost
level. Also skip checking filters under the same conditions, which means that
for a preloaded file or a file that was trivially-moved to the bottom level, its
filter block will eventually expire from the cache.
- added parameters/instance variables in various places in order to propagate the config ("skip_filters") from version_set to block_based_table_reader
- in BlockBasedTable::Rep, this optimization prevents filter from being loaded when the file is opened simply by setting filter_policy = nullptr
- in BlockBasedTable::Get/BlockBasedTable::NewIterator, this optimization prevents filter from being used (even if it was loaded already) by setting filter = nullptr
Test Plan:
updated unit test:
$ ./db_test --gtest_filter=DBTest.OptimizeFiltersForHits
will also run 'make check'
Reviewers: sdong, igor, paultuckfield, anthony, rven, kradhakrishnan, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D51633
Summary: As part of cleaning up dependencies for tech debt week, we are moving ldb and sst_dump tools from util to tools, since they are tools.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48747
Summary:
Separate a new class InternalIterator from class Iterator, when the look-up is done internally, which also means they operate on key with sequence ID and type.
This change will enable potential future optimizations but for now InternalIterator's functions are still the same as Iterator's.
At the same time, separate the cleanup function to a separate class and let both of InternalIterator and Iterator inherit from it.
Test Plan: Run all existing tests.
Reviewers: igor, yhchiang, anthony, kradhakrishnan, IslamAbdelRahman, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48549
Summary: Pass column family ID through TablePropertiesCollectorFactory::CreateTablePropertiesCollector() so that users can identify which column family this file is for and handle it differently.
Test Plan: Add unit test scenarios in tests related to table properties collectors to verify the information passed in is correct.
Reviewers: rven, yhchiang, anthony, kradhakrishnan, igor, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48411
Vijay Nadimpalli