Revision 0454f781c262f8134f6d976295a3290f02724197 authored by Andrew Kryczka on 16 February 2018, 03:30:52 UTC, committed by Facebook Github Bot on 16 February 2018, 03:41:52 UTC
Summary: Calling `std::vector::reserve()` causes memory to be reallocated and then data to be moved. It was called prior to adding every block. This reallocation could be done a huge amount of times, e.g., for users with large index blocks. Instead, we can simply use `std::vector::emplace_back()` in such a way that preserves the no-memory-leak guarantee, while letting the vector decide when to reallocate space. Now I see reallocation/moving happen O(logN) times, rather than O(N) times, where N is the final size of vector. Closes https://github.com/facebook/rocksdb/pull/3508 Differential Revision: D6994228 Pulled By: ajkr fbshipit-source-id: ab7c11e13ff37c8c6c8249be7a79566a4068cd27
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DUMP_FORMAT.md
## RocksDB dump format
The version 1 RocksDB dump format is fairly simple:
1) The dump starts with the magic 8 byte identifier "ROCKDUMP"
2) The magic is followed by an 8 byte big-endian version which is 0x00000001.
3) Next are arbitrarily sized chunks of bytes prepended by 4 byte little endian number indicating how large each chunk is.
4) The first chunk is special and is a json string indicating some things about the creation of this dump. It contains the following keys:
* database-path: The path of the database this dump was created from.
* hostname: The hostname of the machine where the dump was created.
* creation-time: Unix seconds since epoc when this dump was created.
5) Following the info dump the slices paired into are key/value pairs.
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