Commit Graph

4 Commits

Author SHA1 Message Date
Lei Jin
834c67d77f rename FileLevel to LevelFilesBrief / unfriend CompactedDBImpl
Summary:
We have several different types of data structures for file information.
FileLevel is kinda of confusing since it only contains file range and
fd. Rename it to LevelFilesBrief to make it clear.
Unfriend CompactedDBImpl as a by product

Test Plan:
make release / make all
will run full test with all stacked diffs

Reviewers: sdong, yhchiang, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D27585
2014-10-28 10:03:13 -07:00
Lei Jin
2faf49d5f1 use GetContext to replace callback function pointer
Summary:
Intead of passing callback function pointer and its arg on Table::Get()
interface, passing GetContext. This makes the interface cleaner and
possible better perf. Also adding a fast pass for SaveValue()

Test Plan: make all check

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24057
2014-09-29 11:09:09 -07:00
Lei Jin
fbd2dafc9f CompactedDBImpl::MultiGet() for better CuckooTable performance
Summary:
Add the MultiGet API to allow prefetching.
With file size of 1.5G, I configured it to have 0.9 hash ratio that can
fill With 115M keys and result in 2 hash functions, the lookup QPS is
~4.9M/s  vs. 3M/s for Get().
It is tricky to set the parameters right. Since files size is determined
by power-of-two factor, that means # of keys is fixed in each file. With
big file size (thus smaller # of files), we will have more chance to
waste lot of space in the last file - lower space utilization as a
result. Using smaller file size can improve the situation, but that
harms lookup speed.

Test Plan: db_bench

Reviewers: yhchiang, sdong, igor

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23673
2014-09-25 13:34:51 -07:00
Lei Jin
3c68006109 CompactedDBImpl
Summary:
Add a CompactedDBImpl that will enabled when calling OpenForReadOnly()
and the DB only has one level (>0) of files. As a performan comparison,
CuckooTable performs 2.1M/s with CompactedDBImpl vs. 1.78M/s with
ReadOnlyDBImpl.

Test Plan: db_bench

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23553
2014-09-25 11:14:01 -07:00