In HISTORY.md Switch unreleased notes to 3.13

Summary: Prepare release notes for 3.13.

Test Plan: Text only

Reviewers: yhchiang, IslamAbdelRahman, rven, anthony

Reviewed By: anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43665

Fix delete_scheduler_test valgrind error

Summary: Use shared_ptr instead of deleting in destructor

Test Plan: DISABLE_JEMALLOC=1 make delete_scheduler_test -j64 && valgrind --error-exitcode=2 --leak-check=full ./delete_scheduler_test

Reviewers: yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D43659

Avoid type unique_ptr in LogWriterNumber::writer for Windows build break

Summary:
Visual Studio complains about deque<LogWriterNumber> because LogWriterNumber is non-copyable for its unique_ptr member writer. Move away from it, and do explit free.
It is less safe but I can't think of a better way to unblock it.

Test Plan: valgrind check test

Reviewers: anthony, IslamAbdelRahman, kolmike, rven, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43647

Fixing endless loop if seeking to end of key with seq num 0

Summary:
When seeking to the last occurrence of a key with sequence number 0, db_iter
ends up in an endless loop because it seeks to type kValueTypeForSeek
which is larger than kTypeDeletion/kTypeValue. Added test case that triggers
the behavior.

Test Plan: make clean all check

Reviewers: igor, rven, anthony, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D43653

Add util/delete_scheduler_impl.cc to CMakeLists.txt

Summary: util/delete_scheduler_impl.cc is missing CMakeLists.txt, which fails Windows build. Add it.

Test Plan: Build in both of Windows and Linux

Reviewers: anthony, rven, yhchiang, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43641

Add Statistics.getHistogramString() to print more detailed outputs of a histogram

Summary:
Provide a way for users to know more detailed ditribution of a histogram metrics. Example outputs:

Manually add statement
  fprintf(stdout, "%s\n", dbstats->getHistogramString(SST_READ_MICROS).c_str());
Will print out something like:

Count: 989151  Average: 1.7659  StdDev: 1.52
Min: 0.0000  Median: 1.2071  Max: 860.0000
Percentiles: P50: 1.21 P75: 1.70 P99: 5.12 P99.9: 13.67 P99.99: 21.70
------------------------------------------------------
[       0,       1 )   390839  39.513%  39.513% ########
[       1,       2 )   500918  50.641%  90.154% ##########
[       2,       3 )    79358   8.023%  98.177% ##
[       3,       4 )     6297   0.637%  98.813%
[       4,       5 )     1712   0.173%  98.986%
[       5,       6 )     1134   0.115%  99.101%
[       6,       7 )     1222   0.124%  99.224%
[       7,       8 )     1529   0.155%  99.379%
[       8,       9 )     1264   0.128%  99.507%
[       9,      10 )      988   0.100%  99.607%
[      10,      12 )     1378   0.139%  99.746%
[      12,      14 )     1828   0.185%  99.931%
[      14,      16 )      410   0.041%  99.972%
[      16,      18 )       72   0.007%  99.980%
[      18,      20 )       67   0.007%  99.986%
[      20,      25 )      106   0.011%  99.997%
[      25,      30 )       24   0.002%  99.999%
[      30,      35 )        1   0.000% 100.000%
[     250,     300 )        2   0.000% 100.000%
[     300,     350 )        1   0.000% 100.000%
[     800,     900 )        1   0.000% 100.000%

Test Plan: Manually add a print in db_bench and make sure it prints out as expected. Will add some codes to cover the function

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43611

Make DeleteScheduler tests more reliable

Summary: Update DeleteScheduler tests so that they verify the used penalties for waiting instead of measuring the time spent which is not reliable

Test Plan:
make -j64 delete_scheduler_test && ./delete_scheduler_test
COMPILE_WITH_TSAN=1 make -j64 delete_scheduler_test && ./delete_scheduler_test
COMPILE_WITH_ASAN=1 make -j64 delete_scheduler_test && ./delete_scheduler_test

make -j64 db_test && ./db_test --gtest_filter="DBTest.RateLimitedDelete:DBTest.DeleteSchedulerMultipleDBPaths"
COMPILE_WITH_TSAN=1 make -j64 db_test && ./db_test --gtest_filter="DBTest.RateLimitedDelete:DBTest.DeleteSchedulerMultipleDBPaths"
COMPILE_WITH_ASAN=1 make -j64 db_test && ./db_test --gtest_filter="DBTest.RateLimitedDelete:DBTest.DeleteSchedulerMultipleDBPaths"

Reviewers: yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D43635

valgrind_check to exit on test failures

Summary: Currently, valgrind_check doesn't fail on test failures, which creates confusion. valgrind_check should fail if test fails.

Test Plan: Manually change tests to return test failure or cause memory leak and see valgrind_check has the correct behavior.

Reviewers: anthony, yhchiang, IslamAbdelRahman, igor, kradhakrishnan, rven

Reviewed By: rven

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D43629

Fix build failure

Summary: fix the build failure

Test Plan: make all

Reviewers: sdong, IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D43623

Add function 'GetInfoLogList()'

Summary: The list of info log files of a db can be obtained using the new function.

Test Plan: New test in db_test.cc passed.

Reviewers: yhchiang, IslamAbdelRahman, sdong

Reviewed By: sdong

Subscribers: IslamAbdelRahman, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41715