https://github.com/facebook/rocksdb
Revision 36300fbbe3a7fde402152e4a57bbf5cda614d53c authored by Dmitri Smirnov on 01 February 2016, 21:14:37 UTC, committed by Dmitri Smirnov on 01 February 2016, 21:14:37 UTC
This change impacts only non-buffered I/O on Windows. Currently, there is a buffer per RandomAccessFile instance that is protected by a lock. The reason we maintain the buffer is non-buffered I/O requires an aligned buffer to work. XPerf traces demonstrate that we accumulate a considerable wait time while waiting for that lock. This change enables to set random access buffer size to zero which would indicate a per request allocation. We are expecting that allocation expense would be much less than I/O costs plus wait time due to the fact that the memory heap would tend to re-use page aligned allocations especially with the use of Jemalloc. This change does not affect buffer use as a read_ahead_buffer for compaction purposes.
1 parent 3b2a1dd
Tip revision: 36300fbbe3a7fde402152e4a57bbf5cda614d53c authored by Dmitri Smirnov on 01 February 2016, 21:14:37 UTC
Enable per-request buffer allocation in RandomAccessFile
Enable per-request buffer allocation in RandomAccessFile
Tip revision: 36300fb
PATENTS
Additional Grant of Patent Rights Version 2
"Software" means the RocksDB software distributed by Facebook, Inc.
Facebook, Inc. ("Facebook") hereby grants to each recipient of the Software
("you") a perpetual, worldwide, royalty-free, non-exclusive, irrevocable
(subject to the termination provision below) license under any Necessary
Claims, to make, have made, use, sell, offer to sell, import, and otherwise
transfer the Software. For avoidance of doubt, no license is granted under
Facebookâs rights in any patent claims that are infringed by (i) modifications
to the Software made by you or any third party or (ii) the Software in
combination with any software or other technology.
The license granted hereunder will terminate, automatically and without notice,
if you (or any of your subsidiaries, corporate affiliates or agents) initiate
directly or indirectly, or take a direct financial interest in, any Patent
Assertion: (i) against Facebook or any of its subsidiaries or corporate
affiliates, (ii) against any party if such Patent Assertion arises in whole or
in part from any software, technology, product or service of Facebook or any of
its subsidiaries or corporate affiliates, or (iii) against any party relating
to the Software. Notwithstanding the foregoing, if Facebook or any of its
subsidiaries or corporate affiliates files a lawsuit alleging patent
infringement against you in the first instance, and you respond by filing a
patent infringement counterclaim in that lawsuit against that party that is
unrelated to the Software, the license granted hereunder will not terminate
under section (i) of this paragraph due to such counterclaim.
A "Necessary Claim" is a claim of a patent owned by Facebook that is
necessarily infringed by the Software standing alone.
A "Patent Assertion" is any lawsuit or other action alleging direct, indirect,
or contributory infringement or inducement to infringe any patent, including a
cross-claim or counterclaim.
Computing file changes ...
