Summary:
By constraining the probes within cache line(s), we can improve the
cache miss rate thus performance. This probably only makes sense for
in-memory workload so defaults the option to off.
Numbers and comparision can be found in wiki:
https://our.intern.facebook.com/intern/wiki/index.php/Ljin/rocksdb_perf/2014_03_17#Bloom_Filter_Study
Test Plan: benchmarked this change substantially. Will run make all check as well
Reviewers: haobo, igor, dhruba, sdong, yhchiang
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D17133
Summary:
Previous we did rough estimation of subindex size, which in worst case may result in array reallocation.
This patch aims to get the exact size and avoid any reallocation.
Test Plan: make all check
Reviewers: sdong, dhruba, haobo
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D16125
Summary:
PlainTable::Next() should pass the error message from ReadKey(). Now it would return a wrong error message.
Also improve the messages of status when failing to read
Test Plan: make all check
Reviewers: ljin, kailiu, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D16365
Summary:
1. Add some more implementation-aware tests for PlainTable
2. move from a hard-coded one index per 16 rows in one prefix to a configurable number. Also, make hash table ratio = 0 means binary search only. Also fixes some divide 0 risks.
3. Explicitly support total order (only use binary search)
4. some code cleaning up.
Test Plan: make all check
Reviewers: haobo, kailiu
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D16023
Summary:
We are going to expose properties of all tables to end users through "some" db interface.
However, current design doesn't naturally fit for this need, which is because:
1. If a table presents in table cache, we cannot simply return the reference to its table properties, because the table may be destroy after compaction (and we don't want to hold the ref of the version).
2. Copy table properties is OK, but it's slow.
Thus in this diff, I change the table reader's interface to return a shared pointer (for const table properties), instead a const refernce.
Test Plan: `make check` passed
Reviewers: haobo, sdong, dhruba
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15999
Summary: In PlainTable, use one single byte to represent 8 bytes of internal bytes, if seqID = 0 and it is value type (which should be common for bottom most files). It is to save 7 bytes for uncompressed cases.
Test Plan: make all check
Reviewers: haobo, dhruba, kailiu
Reviewed By: haobo
CC: igor, leveldb
Differential Revision: https://reviews.facebook.net/D15489
Summary:
Plain table has been working well and this is just a nit-picking patch,
which is generated during my coding reading. No real functional changes.
only some changes regarding:
* Improve some comments from the perspective a "new" code reader.
* Change some magic number to constant, which can help us to parameterize them
in the future.
* Did some style, naming, C++ convention changes.
* Fix warnings from new "arc lint"
Test Plan: make check
Reviewers: sdong, haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15429
Summary:
Some changes to PlainTable format:
(1) support variable key length
(2) use user defined slice transformer to extract prefixes
(3) Run some test cases against PlainTable in db_test and table_test
Test Plan: test db_test
Reviewers: haobo, kailiu
CC: dhruba, igor, leveldb, nkg-
Differential Revision: https://reviews.facebook.net/D14457
Summary: A bug to fix. IT's already fixed in D14457, but want to check it in sooner to unblock tests
Test Plan: plain_table_db_test
Reviewers: nkg-, haobo
Reviewed By: nkg-
CC: kailiu, leveldb
Differential Revision: https://reviews.facebook.net/D14673
Summary:
This is the last diff that adds the property block to plain table.
The format resembles that of the block-based table: https://github.com/facebook/rocksdb/wiki/Rocksdb-table-format
[data block]
[meta block 1: stats block]
[meta block 2: future extended block]
...
[meta block K: future extended block] (we may add more meta blocks in the future)
[metaindex block]
[index block: we only have the placeholder here, we can add persistent index block in the future]
[Footer: contains magic number, handle to metaindex block and index block]
<end_of_file>
Test Plan: extended existing property block test.
Reviewers: haobo, sdong, dhruba
CC: leveldb
Differential Revision: https://reviews.facebook.net/D14523
Summary:
PlainTable now has a bug of the ordering of indexes for the prefixes in the same bucket. I thought std::map guaranteed key order but it didn't, probably because I didn't use it properly. But seems to me that we don't need to make extra sorting as input prefixes are already sorted. Found by problem by running leaf4 against plain table. Replace the map with a vector. It should performs better too.
After the fix, leaf4 unit tests are passing.
Test Plan:
run plain_table_db_test
Also going to run db_test with plain table in the uncommitted branch.
Reviewers: haobo, kailiu
Reviewed By: haobo
CC: nkg-, leveldb
Differential Revision: https://reviews.facebook.net/D14649
Summary:
PlainTableReader to use a more customized hash table. This patch assumes the SST file is smaller than 2GB:
(1) Every bucket uses 32-bit integer
(2) no key is stored in bucket
(3) use the first bit of the bucket value to distinguish it points to the file offset or a second level index.
This index schema fits the use case that most of prefixes have very small number of keys
Test Plan: plain_table_db_test
Reviewers: haobo, kailiu, dhruba
Reviewed By: haobo
CC: nkg-, leveldb
Differential Revision: https://reviews.facebook.net/D14343
Summary:
A Simple plain table format. No block structure. When creating the table reader, scanning the full table to create indexes.
Test Plan:Add unit test
Reviewers:haobo,dhruba,kailiu
CC:
Task ID: #
Blame Rev:
Lei Jin