0d57d93a06
Summary: Previously, if the jemalloc was built with nonempty string for `--with-jemalloc-prefix`, then `HasJemalloc()` would return false on Linux, so jemalloc would not be used at runtime. On Mac, it would cause a linker failure due to no definitions found for the weak functions declared in "port/jemalloc_helper.h". This should be a rare problem because (1) on Linux the default `--with-jemalloc-prefix` value is the empty string, and (2) Homebrew's build explicitly sets `--with-jemalloc-prefix` to the empty string. However, there are cases where `--with-jemalloc-prefix` is nonempty. For example, when building jemalloc from source on Mac, the default setting is `--with-jemalloc-prefix=je_`. Such jemalloc builds should be usable by RocksDB. The fix is simple. Defining `JEMALLOC_MANGLE` before including "jemalloc.h" causes it to define unprefixed symbols that are aliases for each of the prefixed symbols. Thanks to benesch for figuring this out and explaining it to me. Fixes https://github.com/facebook/rocksdb/issues/1462. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5521 Test Plan: build jemalloc with prefixed symbols: ``` $ ./configure --with-jemalloc-prefix=lol $ make ``` compile rocksdb against it: ``` $ WITH_JEMALLOC_FLAG=1 JEMALLOC=1 EXTRA_LDFLAGS="-L/home/andrew/jemalloc/lib/" EXTRA_CXXFLAGS="-I/home/andrew/jemalloc/include/" make -j12 ./db_bench ``` run db_bench and verify jemalloc actually used: ``` $ ./db_bench -benchmarks=fillrandom -statistics=true -dump_malloc_stats=true -stats_dump_period_sec=1 $ grep jemalloc /tmp/rocksdbtest-1000/dbbench/LOG 2019/06/29-12:20:52.088658 7fc5fb7f6700 [_impl/db_impl.cc:837] ___ Begin jemalloc statistics ___ ... ``` Differential Revision: D16092758 fbshipit-source-id: c2c358346190ed62ceb2a3547a6c4c180b12f7c4 |
||
|---|---|---|
| .. | ||
| win | ||
| jemalloc_helper.h | ||
| likely.h | ||
| port_dirent.h | ||
| port_example.h | ||
| port_posix.cc | ||
| port_posix.h | ||
| port.h | ||
| README | ||
| stack_trace.cc | ||
| stack_trace.h | ||
| sys_time.h | ||
| util_logger.h | ||
| xpress.h | ||
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.