Summary: If we drop column family only from (single) write thread, we can be sure that nobody will drop the column family while we're writing (and our mutex is released). This greatly simplifies my patch that's getting rid of MakeRoomForWrite().

Test Plan: make check, but also running stress test

Reviewers: ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22965

Summary:
That way we can see when this graph goes up and be happy.

Couple of changes:
1. title
2. fix db_bench to delete column families before deleting the DB. this was asserting when compiled in debug mode
3. don't sync manifest when disableDataSync. We discussed this offline. I can move it to separate diff if you'd like

Test Plan: ran it

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22815

Summary: as title

Test Plan: make release

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22935

Fix compaction bug in Cuckoo Table Builder. Use kvs_.size() instead of num_entries in FileSize() method.

Summary: Fix compaction bug in Cuckoo Table Builder. Use kvs_.size() instead of num_entries in FileSize() method. Also added tests.

Test Plan:
make check all
Also ran db_bench to generate multiple files.

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22743

Summary: fixed memory leak in unit test DBIteratorBoundTest

Test Plan: ran valgrind test on my unit test

Reviewers: sdong

Differential Revision: https://reviews.facebook.net/D22911

Summary:
PlainTable takes reference instead of a copy. Keep a copy in the test
code

Test Plan: make asan_check

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22899

N/A

Change-Id: I5b6f9c70aea7d3f3489328834fed323d41106d9f
Signed-off-by: Nliuhuahang <liuhuahang@zerus.co>

Summary:
Simply code by removing code path which does not use Arena
from NewInternalIterator

Test Plan:
make all check
make valgrind_check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22395

Summary:
As a preparation to support updating some options dynamically, I'd like
to first introduce ImmutableOptions, which is a subset of Options that
cannot be changed during the course of a DB lifetime without restart.

ColumnFamily will keep both Options and ImmutableOptions. Any component
below ColumnFamily should only take ImmutableOptions in their
constructor. Other options should be taken from APIs, which will be
allowed to adjust dynamically.

I am yet to make changes to memtable and other related classes to take
ImmutableOptions in their ctor. That can be done in a seprate diff as
this one is already pretty big.

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D22545

1, const qualifiers on return types make no sense and will trigger a compile warning: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]

2, class HistogramImpl has virtual functions and thus should have a virtual destructor

3, with some toolchain, the macro __STDC_FORMAT_MACROS is predefined and thus should be checked before define

Change-Id: I69747a03bfae88671bfbb2637c80d17600159c99
Signed-off-by: Nliuhuahang <liuhuahang@zerus.co>

Summary: It only covers Open() with default column family right now

Test Plan: make release

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22467

Summary:
Before this diff, whenever we Write to non-existing column family, Write() would fail.

This diff adds an option to not fail a Write() when WriteBatch points to non-existing column family. MongoDB said this would be useful for them, since they might have a transaction updating an index that was dropped by another thread. This way, they don't have to worry about checking if all indexes are alive on every write. They don't care if they lose writes to dropped index.

Test Plan: added a small unit test

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22143

Summary: 1. db/db_impl.cc:2324 (DBImpl::BackgroundCompaction) should not raise bg_error_ when column family is dropped during compaction.

Test Plan: 1. db_stress

Reviewers: ljin, yhchiang, dhruba, igor, sdong

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22653

This eliminates the need to remember to call PERF_TIMER_STOP when a section has
been timed. This allows more useful design with the perf timers and enables
possible return value optimizations. Simplistic example:

class Foo {
  public:
    Foo(int v) : m_v(v);
  private:
    int m_v;
}

Foo makeFrobbedFoo(int *errno)
{
  *errno = 0;
  return Foo();
}

Foo bar(int *errno)
{
  PERF_TIMER_GUARD(some_timer);

  return makeFrobbedFoo(errno);
}

int main(int argc, char[] argv)
{
  Foo f;
  int errno;

  f = bar(&errno);

  if (errno)
    return -1;
  return 0;
}

After bar() is called, perf_context.some_timer would be incremented as if
Stop(&perf_context.some_timer) was called at the end, and the compiler is still
able to produce optimizations on the return value from makeFrobbedFoo() through
to main().

Summary: We need to set contbuild for this :)

Test Plan: compiles

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22701

Summary:
I have an application configured with 16 background threads. Write rates are high. L0->L1 compactions is very slow and it limits the concurrency of the system. While it's happening, other 15 threads are idle. However, when there is a need of a flush, that one thread busy with L0->L1 is doing flush, instead of any other 15 threads that are just sitting there.

This diff prevents that. If there are threads that are idle, we don't let flush preempt compaction.

Test Plan: Will run stress test

Reviewers: ljin, sdong, yhchiang

Reviewed By: sdong, yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D22299

Summary:
When reading from kBlockCacheTier, ForwardIterator's internal child iterators
may end up in the incomplete state (read was unable to complete without doing
disk I/O). `ForwardIterator::status()` will correctly report that; however, the
iterator may be stuck in that state until all sub-iterators are rebuilt:

  * `NeedToSeekImmutable()` may return false even if some sub-iterators are
    incomplete
  * one of the child iterators may be an empty iterator without any state other
    that the kIncomplete status (created using `NewErrorIterator()`); seeking on
    any such iterator has no effect -- we need to construct it again

Akin to rebuilding iterators after a superversion bump, this diff makes forward
iterator reset all incomplete child iterators when `Seek()` or `Next()` are
called.

Test Plan: TEST_TMPDIR=/dev/shm/rocksdbtest ROCKSDB_TESTS=TailingIterator ./db_test

Reviewers: igor, sdong, ljin

Reviewed By: ljin

Subscribers: lovro, march, leveldb

Differential Revision: https://reviews.facebook.net/D22575

Summary: It is too expensive to bump ticker to every key/vaue pair

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22527

Summary:
1. remove class InternalFilterPolicy in db/dbformat.h
2. Transformation from internal key to user key is done in filter_block.cc
3. This is a preparation for patch D20979

Test Plan:
make all check
valgrind ./db_test

Reviewers: igor, yhchiang, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22509

Summary:
Based on discussions from t4982833. This is just a short-term fix, I plan to revamp manual compaction process as part of t4982812.

Also, I think we should schedule automatic compactions at the very end of manual compactions, not when we're done with one level. I made that change as part of this diff. Let me know if you disagree.

Test Plan: make check for now

Reviewers: sdong, tnovak, yhchiang, ljin

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22401

Summary: No __thread for ios.

Test Plan: compile works for ios now

Reviewers: ljin, dhruba

Reviewed By: dhruba

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22491

Summary:
- New Uint64 comparator
- Modify Reader and Builder to take custom user comparators instead of bytewise comparator
- Modify logic for choosing unused user key in builder
- Modify iterator logic in reader
- test changes

Test Plan:
cuckoo_table_{builder,reader,db}_test
make check all

Reviewers: ljin, sdong

Reviewed By: ljin

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D22377

Summary: In DBImpl::Recover method, while loading memtables, also check if memtables are empty. Use this in DBImplReadonly to determine whether to lookup memtable or not.

Test Plan:
db_test
make check all

Reviewers: sdong, yhchiang, ljin, igor

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22281

Summary:
Add property 'rocksdb.is-file-deletions-enable'
	 which equals disable_delete_obsole_file_

Test Plan: make all check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22119

Summary: also fix HISTORY.md

Test Plan: make all check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22437

Summary:
It was creating BlockBasedTableOptions object in a loop without calling
destroy()

Test Plan: valgrind ./c_test --leak-check=full --show-reachable=yes

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22431

ReadOptions.total_order_seek to allow total order seek for block-based table when hash index is enabled

Summary: as title

Test Plan: table_test

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22239

Summary: Add a virtual function in table factory that will print table options

Test Plan: make release

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22149

Summary:
I will move compression related options in a separate diff since this
diff is already pretty lengthy.
I guess I will also need to change JNI accordingly :(

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21915

Summary:
I am currently working on a project that uses RocksDB. While debugging some perf issues, I came up across interesting compaction concurrency issue. Namely, I had 15 idle threads and a good comapction to do, but CompactionPicker returned "Compaction nothing to do". Here's how Internal stats looked:

    2014/08/22-08:08:04.551982 7fc7fc3f5700 ------- DUMPING STATS -------
    2014/08/22-08:08:04.552000 7fc7fc3f5700
    ** Compaction Stats [default] **
    Level   Files   Size(MB) Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) RW-Amp W-Amp Rd(MB/s) Wr(MB/s)  Rn(cnt) Rnp1(cnt) Wnp1(cnt) Wnew(cnt)  Comp(sec) Comp(cnt) Avg(sec) Stall(sec) Stall(cnt) Avg(ms)
    ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
      L0     7/5        353   1.0      0.0     0.0      0.0       2.3      2.3    0.0   0.0      0.0      9.4        0         0         0         0        247        46    5.359       8.53          1 8526.25
      L1     2/2         86   1.3      2.6     1.9      0.7       2.6      1.9    2.7   1.3     24.3     24.0       39        19        71        52        109        11    9.938       0.00          0    0.00
      L2    26/0        833   1.3      5.7     1.7      4.0       5.2      1.2    6.3   3.0     15.6     14.2       47       112       147        35        373        44    8.468       0.00          0    0.00
      L3    12/0        505   0.1      0.0     0.0      0.0       0.0      0.0    0.0   0.0      0.0      0.0        0         0         0         0          0         0    0.000       0.00          0    0.00
     Sum    47/7       1778   0.0      8.3     3.6      4.6      10.0      5.4    8.1   4.4     11.6     14.1       86       131       218        87        728       101    7.212       8.53          1 8526.25
     Int     0/0          0   0.0      2.4     0.8      1.6       2.7      1.2   11.5   6.1     12.0     13.6       20        43        63        20        203        23    8.845       0.00          0    0.00
    Flush(GB): accumulative 2.266, interval 0.444
    Stalls(secs): 0.000 level0_slowdown, 0.000 level0_numfiles, 8.526 memtable_compaction, 0.000 leveln_slowdown_soft, 0.000 leveln_slowdown_hard
    Stalls(count): 0 level0_slowdown, 0 level0_numfiles, 1 memtable_compaction, 0 leveln_slowdown_soft, 0 leveln_slowdown_hard

    ** DB Stats **
    Uptime(secs): 336.8 total, 60.4 interval
    Cumulative writes: 61584000 writes, 6480589 batches, 9.5 writes per batch, 1.39 GB user ingest
    Cumulative WAL: 0 writes, 0 syncs, 0.00 writes per sync, 0.00 GB written
    Interval writes: 11235257 writes, 1175050 batches, 9.6 writes per batch, 259.9 MB user ingest
    Interval WAL: 0 writes, 0 syncs, 0.00 writes per sync, 0.00 MB written

To see what happened, go here: https://github.com/facebook/rocksdb/blob/47b452cfcf9b1487d41f886a98bc0d6f95587e90/db/compaction_picker.cc#L430
* The for loop started with level 1, because it has the worst score.
* PickCompactionBySize on L429 returned nullptr because all files were being compacted
* ExpandWhileOverlapping(c) returned true (because that's what it does when it gets nullptr!?)
* for loop break-ed, never trying compactions for level 2 :( :(

This bug was present at least since January. I have no idea how we didn't find this sooner.

Test Plan:
Unit testing compaction picker is hard. I tested this by running my service and observing L0->L1 and L2->L3 compactions in parallel. However, for long-term, I opened the task #4968469. @yhchiang is currently refactoring CompactionPicker, hopefully the new version will be unit-testable ;)

Here's how my compactions look like after the patch:

    2014/08/22-08:50:02.166699 7f3400ffb700 ------- DUMPING STATS -------
    2014/08/22-08:50:02.166722 7f3400ffb700
    ** Compaction Stats [default] **
    Level   Files   Size(MB) Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) RW-Amp W-Amp Rd(MB/s) Wr(MB/s)  Rn(cnt) Rnp1(cnt) Wnp1(cnt) Wnew(cnt)  Comp(sec) Comp(cnt) Avg(sec) Stall(sec) Stall(cnt) Avg(ms)
    ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
      L0     8/5        404   1.5      0.0     0.0      0.0       4.3      4.3    0.0   0.0      0.0      9.6        0         0         0         0        463        88    5.260       0.00          0    0.00
      L1     2/2         60   0.9      4.8     3.9      0.8       4.7      3.9    2.4   1.2     23.9     23.6       80        23       131       108        204        19   10.747       0.00          0    0.00
      L2    23/3        697   1.0     11.6     3.5      8.1      10.9      2.8    6.4   3.1     17.7     16.6       95       242       317        75        669        92    7.268       0.00          0    0.00
      L3    58/14      2207   0.3      6.2     1.6      4.6       5.9      1.3    7.4   3.6     14.6     13.9       43       121       159        38        436        36   12.106       0.00          0    0.00
     Sum    91/24      3368   0.0     22.5     9.1     13.5      25.8     12.4   11.2   6.0     13.0     14.9      218       386       607       221       1772       235    7.538       0.00          0    0.00
     Int     0/0          0   0.0      3.2     0.9      2.3       3.6      1.3   15.3   8.0     12.4     13.7       24        66        89        23        266        27    9.838       0.00          0    0.00
    Flush(GB): accumulative 4.336, interval 0.444
    Stalls(secs): 0.000 level0_slowdown, 0.000 level0_numfiles, 0.000 memtable_compaction, 0.000 leveln_slowdown_soft, 0.000 leveln_slowdown_hard
    Stalls(count): 0 level0_slowdown, 0 level0_numfiles, 0 memtable_compaction, 0 leveln_slowdown_soft, 0 leveln_slowdown_hard

    ** DB Stats **
    Uptime(secs): 577.7 total, 60.1 interval
    Cumulative writes: 116960736 writes, 11966220 batches, 9.8 writes per batch, 2.64 GB user ingest
    Cumulative WAL: 0 writes, 0 syncs, 0.00 writes per sync, 0.00 GB written
    Interval writes: 11643735 writes, 1206136 batches, 9.7 writes per batch, 269.2 MB user ingest
    Interval WAL: 0 writes, 0 syncs, 0.00 writes per sync, 0.00 MB written

Yay for concurrent L0->L1 and L2->L3 compactions!

Reviewers: sdong, yhchiang, ljin

Reviewed By: yhchiang

Subscribers: yhchiang, leveldb

Differential Revision: https://reviews.facebook.net/D22305

Summary:
Fix the error of c_test.c

Test Plan:
make c_test
./c_test

Summary:
Add missing implementaiton of SanitizeDBOptions in simple_table_db_test.cc

Test Plan:
make simple_table_db_test.cc

Summary:
Currently, PlainTable must use mmap_reads.  When PlainTable is used but
allow_mmap_reads is not set, rocksdb will fail in flush.

This diff improve Options sanitization and add MmapReadRequired() to
TableFactory.

Test Plan:
export ROCKSDB_TESTS=PlainTableOptionsSanitizeTest
make db_test -j32
./db_test

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: you, leveldb

Differential Revision: https://reviews.facebook.net/D21939

Summary: A previous change triggered a change by mistake: DestroyDB() will keep info logs under DB directory. Revert the unintended change.

Test Plan: Add a unit test case to verify it.

Reviewers: ljin, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22209