Summary:
ReadaheadRandomAccessFile acts as a transparent layer on top of RandomAccessFile. When a Read() request is issued, it issues a much bigger request to the OS and caches the result. When a new request comes in and we already have the data cached, it doesn't have to issue any requests to the OS.
We add ReadaheadRandomAccessFile layer only when file is read during compactions.
D45105 was incorrectly closed by Phabricator because I committed it to a separate branch (not master), so I'm resubmitting the diff.
Test Plan: make check
Reviewers: MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D45123
Summary:
Up until this point we had DbOptions.num_subcompactions, but
it is semantically more correct to call this max_subcompactions since
we will schedule *up to* DbOptions.max_subcompactions smaller compactions
at a time during a compaction job.
I also added a --subcompactions option to db_bench
Test Plan: make all make check
Reviewers: sdong, igor, anthony, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D45069
Summary: Currently compaction inputs share the same file descriptor and table reader as other foreground threads. It makes fadvise works less predictable. Add options.new_table_reader_for_compaction_inputs to enforce to create a new file descriptor and new table reader for it.
Test Plan: Add the option.
Reviewers: rven, anthony, kradhakrishnan, IslamAbdelRahman, igor, yhchiang
Reviewed By: igor
Subscribers: igor, MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D43311
Summary:
This patch implements DBOptions deserialization and improve
the current implementation of DBOptions serialization by
using a static structure that stores the offset of each
DBOptions member variables to perform serialization and
deserialization instead of using tons of if-then-branch
to determine the mapping between string and variables.
Test Plan: Added test in options_test.cc
Reviewers: igor, anthony, sdong, IslamAbdelRahman
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D44097
Summary: as title
Test Plan: ./db_test
Reviewers: sdong, yhchiang, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28269
Summary: as title
Test Plan:
make all check
I will think a way to set up stress test for this
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D23055
