- 23 8月, 2013 5 次提交
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由 Jim Paton 提交于
Summary: This patch adds three new MemTableRep's: UnsortedRep, PrefixHashRep, and VectorRep. UnsortedRep stores keys in an std::unordered_map of std::sets. When an iterator is requested, it dumps the keys into an std::set and iterates over that. VectorRep stores keys in an std::vector. When an iterator is requested, it creates a copy of the vector and sorts it using std::sort. The iterator accesses that new vector. PrefixHashRep stores keys in an unordered_map mapping prefixes to ordered sets. I also added one API change. I added a function MemTableRep::MarkImmutable. This function is called when the rep is added to the immutable list. It doesn't do anything yet, but it seems like that could be useful. In particular, for the vectorrep, it means we could elide the extra copy and just sort in place. The only reason I haven't done that yet is because the use of the ArenaAllocator complicates things (I can elaborate on this if needed). Test Plan: make -j32 check ./db_stress --memtablerep=vector ./db_stress --memtablerep=unsorted ./db_stress --memtablerep=prefixhash --prefix_size=10 Reviewers: dhruba, haobo, emayanke Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12117
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https://reviews.facebook.net/D10917由 Xing Jin 提交于
Summary: Pull Mark's patch and slightly revise it. I revised another place in db_impl.cc with similar new formula. Test Plan: make all check. Also run "time ./db_bench --num=2500000000 --numdistinct=2200000000". It has run for 20+ hours and hasn't finished. Looks good so far: Installed stack trace handler for SIGILL SIGSEGV SIGBUS SIGABRT LevelDB: version 2.0 Date: Tue Aug 20 23:11:55 2013 CPU: 32 * Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz CPUCache: 20480 KB Keys: 16 bytes each Values: 100 bytes each (50 bytes after compression) Entries: 2500000000 RawSize: 276565.6 MB (estimated) FileSize: 157356.3 MB (estimated) Write rate limit: 0 Compression: snappy WARNING: Assertions are enabled; benchmarks unnecessarily slow ------------------------------------------------ DB path: [/tmp/leveldbtest-3088/dbbench] fillseq : 7202.000 micros/op 138 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] fillsync : 7148.000 micros/op 139 ops/sec; (2500000 ops) DB path: [/tmp/leveldbtest-3088/dbbench] fillrandom : 7105.000 micros/op 140 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] overwrite : 6930.000 micros/op 144 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] readrandom : 1.020 micros/op 980507 ops/sec; (0 of 2500000000 found) DB path: [/tmp/leveldbtest-3088/dbbench] readrandom : 1.021 micros/op 979620 ops/sec; (0 of 2500000000 found) DB path: [/tmp/leveldbtest-3088/dbbench] readseq : 113.000 micros/op 8849 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] readreverse : 102.000 micros/op 9803 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] Created bg thread 0x7f0ac17f7700 compact : 111701.000 micros/op 8 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] readrandom : 1.020 micros/op 980376 ops/sec; (0 of 2500000000 found) DB path: [/tmp/leveldbtest-3088/dbbench] readseq : 120.000 micros/op 8333 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] readreverse : 29.000 micros/op 34482 ops/sec; DB path: [/tmp/leveldbtest-3088/dbbench] ... finished 618100000 ops Reviewers: MarkCallaghan, haobo, dhruba, chip Reviewed By: dhruba Differential Revision: https://reviews.facebook.net/D12441
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由 Tyler Harter 提交于
This reverts commit c2bd8f48.
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由 Tyler Harter 提交于
Summary: If use_prefix_filters is set and read_range>1, then the random seeks will set a the prefix filter to be the prefix of the key which was randomly selected as the target. Still need to add statistics (perhaps in a separate diff). Test Plan: ./db_bench --benchmarks=fillseq,prefixscanrandom --num=10000000 --statistics=1 --use_prefix_blooms=1 --use_prefix_api=1 --bloom_bits=10 Reviewers: dhruba Reviewed By: dhruba CC: leveldb, haobo Differential Revision: https://reviews.facebook.net/D12273
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由 Simha Venkataramaiah 提交于
Summary: An api to query the level, key ranges, size etc for each SST file and an api to delete a specific file from the db and all associated state in the bookkeeping datastructures. Notes: Editing the manifest version does not release the obsolete files right away. However deleting the file directly will mess up the iterator. We may need a more aggressive/timely file deletion api. I have used std::unique_ptr - will switch to boost:: since this is external. thoughts? Unit test is fragile right now as it expects the compaction at certain levels. Test Plan: unittest Reviewers: dhruba, vamsi, emayanke CC: zshao, leveldb, haobo Task ID: # Blame Rev:
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- 22 8月, 2013 2 次提交
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由 Jim Paton 提交于
Summary: Sometimes you don't need to iterate through the whole WriteBatch. This diff makes the Handler member functions return a bool that indicates whether to abort or not. If they return true, the iteration stops. One thing I just thought of is that this will break backwards-compability. Maybe it would be better to add a virtual member function WriteBatch::Handler::ShouldAbort() that returns false by default. Comments requested. I still have to add a new unit test for the abort code, but let's finalize the API first. Test Plan: make -j32 check Reviewers: dhruba, haobo, vamsi, emayanke Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12339
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由 Haobo Xu 提交于
Summary: Was going through the iterator related code, did some cleanup along the way. Basically replaced array with vector and adopted range based loop where applicable. Test Plan: make check; make valgrind_check Reviewers: dhruba, emayanke Reviewed By: emayanke CC: leveldb Differential Revision: https://reviews.facebook.net/D12435
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- 21 8月, 2013 1 次提交
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由 Deon Nicholas 提交于
Test Plan: - make all check; - make release; - make stringappend_test; ./stringappend_test Reviewers: haobo, emayanke Reviewed By: haobo CC: leveldb, kailiu Differential Revision: https://reviews.facebook.net/D12381
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- 20 8月, 2013 2 次提交
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由 Mayank Agarwal 提交于
Summary: Also expanded class LogFile to have startSequene and FileSize and exposed it publicly Test Plan: make all check Reviewers: dhruba, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12087
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由 Deon Nicholas 提交于
Summary: -Added null checks and revisions to DBIter::MergeValuesNewToOld() -Added DBIter test to stringappend_test -Major fix with Merge and TTL More plans for fixes later. Test Plan: -make clean; make stringappend_test -j 32; ./stringappend_test -make all check; Reviewers: haobo, emayanke, vamsi, dhruba Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D12315
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- 16 8月, 2013 3 次提交
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由 Mayank Agarwal 提交于
Summary: statistic for sequence number is needed by wormhole. setTickerCount is demanded for this statistic. I can't simply recordTick(max_sequence) when db recovers because the statistic iobject is owned by client and may/may not be reset during reopen. Eg. statistic is reset in mcrocksdb whereas it is not in db_stress. Therefore it is best to go with setTickerCount Test Plan: ./db_stress ... --statistics=1 and observed expected sequence number Reviewers: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12327
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由 Deon Nicholas 提交于
Summary: In release, "found variable assigned but not used anywhere". Changed it to work with assert. Someone accept this :). Test Plan: make release -j 32 Reviewers: haobo, dhruba, emayanke Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D12309
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由 Deon Nicholas 提交于
Summary: Updated db_bench and utilities/merge_operators.h to allow for dynamic benchmarking of merge operators in db_bench. Added a new test (--benchmarks=mergerandom), which performs a bunch of random Merge() operations over random keys. Also added a "--merge_operator=" flag so that the tester can easily benchmark different merge operators. Currently supports the PutOperator and UInt64Add operator. Support for stringappend or list append may come later. Test Plan: 1. make db_bench 2. Test the PutOperator (simulating Put) as follows: ./db_bench --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom --merge_operator=put --threads=2 3. Test the UInt64AddOperator (simulating numeric addition) similarly: ./db_bench --value_size=8 --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom --merge_operator=uint64add --threads=2 Reviewers: haobo, dhruba, zshao, MarkCallaghan Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D11535
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- 15 8月, 2013 3 次提交
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由 Xing Jin 提交于
Summary: Minor fix to current codes, including: coding style, output format, comments. No major logic change. There are only 2 real changes, please see my inline comments. Test Plan: make all check Reviewers: haobo, dhruba, emayanke Differential Revision: https://reviews.facebook.net/D12297
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由 Jim Paton 提交于
Summary: This patch adds the ability for the user to add sequences of arbitrary data (blobs) to write batches. These blobs are saved to the log along with everything else in the write batch. You can add multiple blobs per WriteBatch and the ordering of blobs, puts, merges, and deletes are preserved. Blobs are not saves to SST files. RocksDB ignores blobs in every way except for writing them to the log. Before committing this patch, I need to add some test code. But I'm submitting it now so people can comment on the API. Test Plan: make -j32 check Reviewers: dhruba, haobo, vamsi Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12195
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由 Haobo Xu 提交于
Summary: As title. No locking/atomic is needed due to thread local. There is also no need to modify the existing client interface, in order to expose related counters. perf_context_test shows a simple example of retrieving the number of user key comparison done for each put and get call. More counters could be added later. Sample output ./perf_context_test 1000000 ==== Test PerfContextTest.KeyComparisonCount Inserting 1000000 key/value pairs ... total user key comparison get: 43446523 total user key comparison put: 8017877 max user key comparison get: 88939 avg user key comparison get:43 Basically, the current skiplist does well on average, but could perform poorly in extreme cases. Test Plan: run perf_context_test <total number of entries to put/get> Reviewers: dhruba Differential Revision: https://reviews.facebook.net/D12225
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- 14 8月, 2013 3 次提交
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由 Mayank Agarwal 提交于
Summary: With Merge returning bool, it can keep failing silently(eg. While faling to fetch timestamp in TTL). We need to detect this through a rocksdb counter which can get bumped whenever Merge returns false. This will also be super-useful for the mcrocksdb-counter service where Merge may fail. Added a counter NUMBER_MERGE_FAILURES and appropriately updated db/merge_helper.cc I felt that it would be better to directly add counter-bumping in Merge as a default function of MergeOperator class but user should not be aware of this, so this approach seems better to me. Test Plan: make all check Reviewers: dnicholas, haobo, dhruba, vamsi CC: leveldb Differential Revision: https://reviews.facebook.net/D12129
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由 Tyler Harter 提交于
Summary: Similar to v2 (db and table code understands prefixes), but use ReadOptions as in v3. Also, make the CreateFilter code faster and cleaner. Test Plan: make db_test; export LEVELDB_TESTS=PrefixScan; ./db_test Reviewers: dhruba Reviewed By: dhruba CC: haobo, emayanke Differential Revision: https://reviews.facebook.net/D12027
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由 sumeet 提交于
Summary: If we have same compaction filter for each compaction, application cannot know about the different compaction processes. Later on, we can put in more details in compaction filter for the application to consume and use it according to its needs. For e.g. In the universal compaction, we have a compaction process involving all the files while others don't involve all the files. Applications may want to collect some stats only when during full compaction. Test Plan: run existing unit tests Reviewers: haobo, dhruba Reviewed By: dhruba CC: xinyaohu, leveldb Differential Revision: https://reviews.facebook.net/D12057
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- 10 8月, 2013 2 次提交
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由 Dhruba Borthakur 提交于
Summary: The pre-existing code was purging a DeleteMarker if thay key did not exist in deeper levels. But in the Universal Compaction Style, all files are in Level0. For compaction runs that did not include the earliest file, we were erroneously purging the DeleteMarkers. The fix is to purge DeleteMarkers only if the compaction includes the earlist file. Test Plan: DBTest.Randomized triggers this code path. Differential Revision: https://reviews.facebook.net/D12081
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由 Xing Jin 提交于
Summary: Continue fixing existing unit tests for universal compaction. I have tried to apply universal compaction to all unit tests those haven't called ChangeOptions(). I left a few which are either apparently not applicable to universal compaction (because they check files/keys/values at level 1 or above levels), or apparently not related to compaction (e.g., open a file, open a db). I also add a new unit test for universal compaction. Good news is I didn't see any bugs during this round. Test Plan: Ran "make all check" yesterday. Has rebased and is rerunning Reviewers: haobo, dhruba Differential Revision: https://reviews.facebook.net/D12135
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- 09 8月, 2013 1 次提交
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由 Haobo Xu 提交于
Summary: Currently, VersionEdit::DebugString always display internal keys in the original ascii format. This could cause manifest dump to be truncated if internal keys contain special charactors (like null). Also added an option --input_key_hex for ldb idump to indicate that the passed in user keys are in hex. Test Plan: run ldb manifest_dump Reviewers: dhruba, emayanke CC: leveldb Differential Revision: https://reviews.facebook.net/D12111
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- 08 8月, 2013 1 次提交
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由 Xing Jin 提交于
Summary: This is the first step to fix unit tests and bugs for universal compactiion. I added universal compaction option to ChangeOptions(), and fixed all unit tests calling ChangeOptions(). Some of these tests obviously assume more than 1 level and check file number/values in level 1 or above levels. I set kSkipUniversalCompaction for these tests. The major bug I found is manual compaction with universal compaction never stops. I have put a fix for it. I have also set universal compaction as the default compaction and found at least 20+ unit tests failing. I haven't looked into the details. The next step is to check all unit tests without calling ChangeOptions(). Test Plan: make all check Reviewers: dhruba, haobo Differential Revision: https://reviews.facebook.net/D12051
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- 07 8月, 2013 1 次提交
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由 Deon Nicholas 提交于
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- 06 8月, 2013 4 次提交
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由 Deon Nicholas 提交于
Summary: Here are the major changes to the Merge Interface. It has been expanded to handle cases where the MergeOperator is not associative. It does so by stacking up merge operations while scanning through the key history (i.e.: during Get() or Compaction), until a valid Put/Delete/end-of-history is encountered; it then applies all of the merge operations in the correct sequence starting with the base/sentinel value. I have also introduced an "AssociativeMerge" function which allows the user to take advantage of associative merge operations (such as in the case of counters). The implementation will always attempt to merge the operations/operands themselves together when they are encountered, and will resort to the "stacking" method if and only if the "associative-merge" fails. This implementation is conjectured to allow MergeOperator to handle the general case, while still providing the user with the ability to take advantage of certain efficiencies in their own merge-operator / data-structure. NOTE: This is a preliminary diff. This must still go through a lot of review, revision, and testing. Feedback welcome! Test Plan: -This is a preliminary diff. I have only just begun testing/debugging it. -I will be testing this with the existing MergeOperator use-cases and unit-tests (counters, string-append, and redis-lists) -I will be "desk-checking" and walking through the code with the help gdb. -I will find a way of stress-testing the new interface / implementation using db_bench, db_test, merge_test, and/or db_stress. -I will ensure that my tests cover all cases: Get-Memtable, Get-Immutable-Memtable, Get-from-Disk, Iterator-Range-Scan, Flush-Memtable-to-L0, Compaction-L0-L1, Compaction-Ln-L(n+1), Put/Delete found, Put/Delete not-found, end-of-history, end-of-file, etc. -A lot of feedback from the reviewers. Reviewers: haobo, dhruba, zshao, emayanke Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D11499
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由 Jim Paton 提交于
Summary: This diff adds histogram stats for soft_rate_limit stalls. It also renames the old rate_limit stats to hard_rate_limit. Test Plan: make -j32 check Reviewers: dhruba, haobo, MarkCallaghan Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12021
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由 Mayank Agarwal 提交于
Summary: rocksdb replicaiton will need this when writing value+TS from master to slave 'as is' Test Plan: make Reviewers: dhruba, vamsi, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11919
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由 Jim Paton 提交于
Summary: This diff adds support for both soft and hard rate limiting. The following changes are included: 1) Options.rate_limit is renamed to Options.hard_rate_limit. 2) Options.rate_limit_delay_milliseconds is renamed to Options.rate_limit_delay_max_milliseconds. 3) Options.soft_rate_limit is added. 4) If the maximum compaction score is > hard_rate_limit and rate_limit_delay_max_milliseconds == 0, then writes are delayed by 1 ms at a time until the max compaction score falls below hard_rate_limit. 5) If the max compaction score is > soft_rate_limit but <= hard_rate_limit, then writes are delayed by 0-1 ms depending on how close we are to hard_rate_limit. 6) Users can disable 4 by setting hard_rate_limit = 0. They can add a limit to the maximum amount of time waited by setting rate_limit_delay_max_milliseconds > 0. Thus, the old behavior can be preserved by setting soft_rate_limit = 0, which is the default. Test Plan: make -j32 check ./db_stress Reviewers: dhruba, haobo, MarkCallaghan Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D12003
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- 02 8月, 2013 2 次提交
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由 Mayank Agarwal 提交于
Summary: Implemented a TtlMergeOperator class which inherits from MergeOperator and is TTL aware. It strips out timestamp from existing_value and attaches timestamp to new_value, calling user-provided-Merge in between. Test Plan: make all check Reviewers: haobo, dhruba Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D11775
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由 Mayank Agarwal 提交于
Expand KeyMayExist to return the proper value if it can be found in memory and also check block_cache Summary: Removed KeyMayExistImpl because KeyMayExist demanded Get like semantics now. Removed no_io from memtable and imm because we need the proper value now and shouldn't just stop when we see Merge in memtable. Added checks to block_cache. Updated documentation and unit-test Test Plan: make all check;db_stress for 1 hour Reviewers: dhruba, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11853
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- 01 8月, 2013 2 次提交
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由 Jim Paton 提交于
Summary: Currently, when a certain number of level0 files (level0_slowdown_writes_trigger) are present, RocksDB will slow down each write by 1ms. There is a second limit of level0 files at which RocksDB will stop writes altogether (level0_stop_writes_trigger). This patch enables the user to supply a third parameter specifying the number of files at which Rocks will start slowing down writes (level0_start_slowdown_writes). When this number is reached, Rocks will slow down writes as a quadratic function of level0_slowdown_writes_trigger - num_level0_files. For some workloads, this improves latency and throughput. I will post some stats momentarily in https://our.intern.facebook.com/intern/tasks/?t=2613384. Test Plan: make -j32 check ./db_stress ./db_bench Reviewers: dhruba, haobo, MarkCallaghan, xjin Reviewed By: xjin CC: leveldb, xjin, zshao Differential Revision: https://reviews.facebook.net/D11859
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由 Xing Jin 提交于
Summary: Add an option for arena block size, default value 4096 bytes. Arena will allocate blocks with such size. I am not sure about passing parameter to skiplist in the new virtualized framework, though I talked to Jim a bit. So add Jim as reviewer. Test Plan: new unit test, I am running db_test. For passing paramter from configured option to Arena, I tried tests like: TEST(DBTest, Arena_Option) { std::string dbname = test::TmpDir() + "/db_arena_option_test"; DestroyDB(dbname, Options()); DB* db = nullptr; Options opts; opts.create_if_missing = true; opts.arena_block_size = 1000000; // tested 99, 999999 Status s = DB::Open(opts, dbname, &db); db->Put(WriteOptions(), "a", "123"); } and printed some debug info. The results look good. Any suggestion for such a unit-test? Reviewers: haobo, dhruba, emayanke, jpaton Reviewed By: dhruba CC: leveldb, zshao Differential Revision: https://reviews.facebook.net/D11799
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- 30 7月, 2013 3 次提交
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由 Jim Paton 提交于
Summary: After my patch for stall histograms, there are redundant calls to NowMicros() by both the stop watches and DBImpl::MakeRoomForWrites. So I removed the redundant calls such that the information is gotten from the stopwatch. Test Plan: make clean make -j32 check Reviewers: dhruba, haobo, MarkCallaghan Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11883
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由 Jim Paton 提交于
Summary: Currently, merge_test uses /tmp/testdb for the test database. It should really use something more specific to merge_test. Most of the other tests use test::TmpDir() + "/<test name>db". This patch implements such behavior for merge_test; it makes merge_test use test::TmpDir() + "/merge_testdb" Test Plan: make clean make -j32 merge_test ./merge_test Reviewers: dhruba, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11877
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由 Jim Paton 提交于
Summary: Previously, statistics are kept on how much time is spent on stalls of different types. This patch adds support for keeping number of stalls of each type. For example, instead of just reporting how many microseconds are spent waiting for memtables to be compacted, it will also report how many times a write stalled for that to occur. Test Plan: make -j32 check ./db_stress # Not really sure what else should be done... Reviewers: dhruba, MarkCallaghan, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11841
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- 25 7月, 2013 2 次提交
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由 Dhruba Borthakur 提交于
Summary: The target file size should be valid value. Only if UniversalCompactionStyle is enabled then set max file size to be LLONG_MAX. Test Plan: Reviewers: CC: Task ID: # Blame Rev:
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由 Dhruba Borthakur 提交于
Revert 6fbe4e98: If disable wal is set, then batch commits are avoided Summary: Revert "If disable wal is set, then batch commits are avoided" because keeping the mutex while inserting into the skiplist means that readers and writes are all serialized on the mutex. Test Plan: Reviewers: CC: Task ID: # Blame Rev:
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- 24 7月, 2013 3 次提交
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由 Jim Paton 提交于
Summary: This diff virtualizes the skiplist interface so that users can provide their own implementation of a backing store for MemTables. Eventually, the backing store will be responsible for its own synchronization, allowing users (and us) to experiment with different lockless implementations. Test Plan: make clean make -j32 check ./db_stress Reviewers: dhruba, emayanke, haobo Reviewed By: dhruba CC: leveldb Differential Revision: https://reviews.facebook.net/D11739
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由 Dhruba Borthakur 提交于
Summary: rocksdb uses batch commit to write to transaction log. But if disable wal is set, then writes to transaction log are anyways avoided. In this case, there is not much value-add to batch things, batching can cause unnecessary delays to Puts(). This patch avoids batching when disableWal is set. Test Plan: make check. I am running db_stress now. Reviewers: haobo Reviewed By: haobo CC: leveldb Differential Revision: https://reviews.facebook.net/D11763
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由 Mayank Agarwal 提交于
Summary: Introduced KeyMayExist checking during writebatch-delete and removed from Outer Delete API because it uses writebatch-delete. Added code to skip getting Table from disk if not already present in table_cache. Some renaming of variables. Introduced KeyMayExistImpl which allows checking since specified sequence number in GetImpl useful to check partially written writebatch. Changed KeyMayExist to not be pure virtual and provided a default implementation. Expanded unit-tests in db_test to check appropriately. Ran db_stress for 1 hour with ./db_stress --max_key=100000 --ops_per_thread=10000000 --delpercent=50 --filter_deletes=1 --statistics=1. Test Plan: db_stress;make check Reviewers: dhruba, haobo Reviewed By: dhruba CC: leveldb, xjin Differential Revision: https://reviews.facebook.net/D11745
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