rocksdb

fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph

History

Peter Dillinger 13ded69484 Built-in support for generating unique IDs, bug fix (#8708 ) Summary: Env::GenerateUniqueId() works fine on Windows and on POSIX where /proc/sys/kernel/random/uuid exists. Our other implementation is flawed and easily produces collision in a new multi-threaded test. As we rely more heavily on DB session ID uniqueness, this becomes a serious issue. This change combines several individually suitable entropy sources for reliable generation of random unique IDs, with goal of uniqueness and portability, not cryptographic strength nor maximum speed. Specifically: * Moves code for getting UUIDs from the OS to port::GenerateRfcUuid rather than in Env implementation details. Callers are now told whether the operation fails or succeeds. * Adds an internal API GenerateRawUniqueId for generating high-quality 128-bit unique identifiers, by combining entropy from three "tracks": * Lots of info from default Env like time, process id, and hostname. * std::random_device * port::GenerateRfcUuid (when working) * Built-in implementations of Env::GenerateUniqueId() will now always produce an RFC 4122 UUID string, either from platform-specific API or by converting the output of GenerateRawUniqueId. DB session IDs now use GenerateRawUniqueId while DB IDs (not as critical) try to use port::GenerateRfcUuid but fall back on GenerateRawUniqueId with conversion to an RFC 4122 UUID. GenerateRawUniqueId is declared and defined under env/ rather than util/ or even port/ because of the Env dependency. Likely follow-up: enhance GenerateRawUniqueId to be faster after the first call and to guarantee uniqueness within the lifetime of a single process (imparting the same property onto DB session IDs). Pull Request resolved: https://github.com/facebook/rocksdb/pull/8708 Test Plan: A new mini-stress test in env_test checks the various public and internal APIs for uniqueness, including each track of GenerateRawUniqueId individually. We can't hope to verify anywhere close to 128 bits of entropy, but it can at least detect flaws as bad as the old code. Serial execution of the new tests takes about 350 ms on my machine. Reviewed By: zhichao-cao, mrambacher Differential Revision: D30563780 Pulled By: pdillinger fbshipit-source-id: de4c9ff4b2f581cf784fcedb5f39f16e5185c364		3 years ago
..
win	Built-in support for generating unique IDs, bug fix (#8708 )	3 years ago
README	reverting disastrous MOE commit, returning to r21	14 years ago
jemalloc_helper.h	jemalloc_helper: Limit the mm_malloc.h hack to glibc on linux (#8425 )	4 years ago
lang.h	Standardize on GCC for TSAN conditional compilation (#8543 )	3 years ago
likely.h	Support pragma once in all header files and cleanup some warnings (#4339 )	6 years ago
malloc.h	Charge block cache for cache internal usage (#5797 )	5 years ago
port.h	Change RocksDB License	8 years ago
port_dirent.h	Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433 )	5 years ago
port_example.h	Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433 )	5 years ago
port_posix.cc	Built-in support for generating unique IDs, bug fix (#8708 )	3 years ago
port_posix.h	Built-in support for generating unique IDs, bug fix (#8708 )	3 years ago
stack_trace.cc	Standardize on GCC for TSAN conditional compilation (#8543 )	3 years ago
stack_trace.h	Fault injection in db_stress (#6538 )	5 years ago
sys_time.h	Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433 )	5 years ago
util_logger.h	Move some logging related files to logging/ (#5387 )	6 years ago
xpress.h	Change RocksDB License	8 years ago

README

This directory contains interfaces and implementations that isolate the
rest of the package from platform details.

Code in the rest of the package includes "port.h" from this directory.
"port.h" in turn includes a platform specific "port_<platform>.h" file
that provides the platform specific implementation.

See port_posix.h for an example of what must be provided in a platform
specific header file.