Summary:
Based on https://github.com/facebook/rocksdb/issues/843
It looks that when the data is hot we spend significant amount of time moving data out of RocksDB blocks. This patch reduce moving memory when possible
Original performance
```
$ time ./ldb --db=/home/tec/local/ellina_test/testdb scan > /dev/null
real 0m16.736s
user 0m11.993s
sys 0m4.725s
```
Performance after reducing memcpy
```
$ time ./ldb --db=/home/tec/local/ellina_test/testdb scan > /dev/null
real 0m11.590s
user 0m6.983s
sys 0m4.595s
```
Test Plan:
dump the output of the scan into 2 files and verifying the are exactly the same
make check
Reviewers: sdong, yhchiang, anthony, rven, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D51093
Summary: As part of cleaning up dependencies for tech debt week, we are moving ldb and sst_dump tools from util to tools, since they are tools.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48747
Summary:
This is first step of my effort to reduce size of librocksdb.a for use in mobile.
ldb object files are huge and are ment to be used as a command line tool. I moved them to `tools/` directory and include them only when compiling `ldb`
This diff reduced librocksdb.a from 42MB to 39MB on my mac (not stripped).
Test Plan: ran ldb
Reviewers: dhruba, haobo, sdong, ljin, yhchiang
Reviewed By: yhchiang
CC: leveldb
Differential Revision: https://reviews.facebook.net/D17823
