Building and installing a packaged release of jemalloc can be as simple as typing the following while in the root directory of the source tree: ./configure make make install If building from unpackaged developer sources, the simplest command sequence that might work is: ./autogen.sh make dist make make install Note that documentation is not built by the default target because doing so would create a dependency on xsltproc in packaged releases, hence the requirement to either run 'make dist' or avoid installing docs via the various install_* targets documented below. === Advanced configuration ===================================================== The 'configure' script supports numerous options that allow control of which functionality is enabled, where jemalloc is installed, etc. Optionally, pass any of the following arguments (not a definitive list) to 'configure': --help Print a definitive list of options. --prefix= Set the base directory in which to install. For example: ./configure --prefix=/usr/local will cause files to be installed into /usr/local/include, /usr/local/lib, and /usr/local/man. --with-version=..--g Use the specified version string rather than trying to generate one (if in a git repository) or use existing the VERSION file (if present). --with-rpath= Embed one or more library paths, so that libjemalloc can find the libraries it is linked to. This works only on ELF-based systems. --with-mangling= Mangle public symbols specified in which is a comma-separated list of name:mangled pairs. For example, to use ld's --wrap option as an alternative method for overriding libc's malloc implementation, specify something like: --with-mangling=malloc:__wrap_malloc,free:__wrap_free[...] Note that mangling happens prior to application of the prefix specified by --with-jemalloc-prefix, and mangled symbols are then ignored when applying the prefix. --with-jemalloc-prefix= Prefix all public APIs with . For example, if is "prefix_", API changes like the following occur: malloc() --> prefix_malloc() malloc_conf --> prefix_malloc_conf /etc/malloc.conf --> /etc/prefix_malloc.conf MALLOC_CONF --> PREFIX_MALLOC_CONF This makes it possible to use jemalloc at the same time as the system allocator, or even to use multiple copies of jemalloc simultaneously. By default, the prefix is "", except on OS X, where it is "je_". On OS X, jemalloc overlays the default malloc zone, but makes no attempt to actually replace the "malloc", "calloc", etc. symbols. --without-export Don't export public APIs. This can be useful when building jemalloc as a static library, or to avoid exporting public APIs when using the zone allocator on OSX. --with-private-namespace= Prefix all library-private APIs with je_. For shared libraries, symbol visibility mechanisms prevent these symbols from being exported, but for static libraries, naming collisions are a real possibility. By default, is empty, which results in a symbol prefix of je_ . --with-install-suffix= Append to the base name of all installed files, such that multiple versions of jemalloc can coexist in the same installation directory. For example, libjemalloc.so.0 becomes libjemalloc.so.0. --with-malloc-conf= Embed as a run-time options string that is processed prior to the malloc_conf global variable, the /etc/malloc.conf symlink, and the MALLOC_CONF environment variable. For example, to change the default chunk size to 256 KiB: --with-malloc-conf=lg_chunk:18 --disable-cc-silence Disable code that silences non-useful compiler warnings. This is mainly useful during development when auditing the set of warnings that are being silenced. --enable-debug Enable assertions and validation code. This incurs a substantial performance hit, but is very useful during application development. Implies --enable-ivsalloc. --enable-code-coverage Enable code coverage support, for use during jemalloc test development. Additional testing targets are available if this option is enabled: coverage coverage_unit coverage_integration coverage_stress These targets do not clear code coverage results from previous runs, and there are interactions between the various coverage targets, so it is usually advisable to run 'make clean' between repeated code coverage runs. --disable-stats Disable statistics gathering functionality. See the "opt.stats_print" option documentation for usage details. --enable-ivsalloc Enable validation code, which verifies that pointers reside within jemalloc-owned chunks before dereferencing them. This incurs a minor performance hit. --enable-prof Enable heap profiling and leak detection functionality. See the "opt.prof" option documentation for usage details. When enabled, there are several approaches to backtracing, and the configure script chooses the first one in the following list that appears to function correctly: + libunwind (requires --enable-prof-libunwind) + libgcc (unless --disable-prof-libgcc) + gcc intrinsics (unless --disable-prof-gcc) --enable-prof-libunwind Use the libunwind library (http://www.nongnu.org/libunwind/) for stack backtracing. --disable-prof-libgcc Disable the use of libgcc's backtracing functionality. --disable-prof-gcc Disable the use of gcc intrinsics for backtracing. --with-static-libunwind= Statically link against the specified libunwind.a rather than dynamically linking with -lunwind. --disable-tcache Disable thread-specific caches for small objects. Objects are cached and released in bulk, thus reducing the total number of mutex operations. See the "opt.tcache" option for usage details. --disable-munmap Disable virtual memory deallocation via munmap(2); instead keep track of the virtual memory for later use. munmap() is disabled by default (i.e. --disable-munmap is implied) on Linux, which has a quirk in its virtual memory allocation algorithm that causes semi-permanent VM map holes under normal jemalloc operation. --disable-fill Disable support for junk/zero filling of memory, quarantine, and redzones. See the "opt.junk", "opt.zero", "opt.quarantine", and "opt.redzone" option documentation for usage details. --disable-valgrind Disable support for Valgrind. --disable-zone-allocator Disable zone allocator for Darwin. This means jemalloc won't be hooked as the default allocator on OSX/iOS. --enable-utrace Enable utrace(2)-based allocation tracing. This feature is not broadly portable (FreeBSD has it, but Linux and OS X do not). --enable-xmalloc Enable support for optional immediate termination due to out-of-memory errors, as is commonly implemented by "xmalloc" wrapper function for malloc. See the "opt.xmalloc" option documentation for usage details. --enable-lazy-lock Enable code that wraps pthread_create() to detect when an application switches from single-threaded to multi-threaded mode, so that it can avoid mutex locking/unlocking operations while in single-threaded mode. In practice, this feature usually has little impact on performance unless thread-specific caching is disabled. --disable-tls Disable thread-local storage (TLS), which allows for fast access to thread-local variables via the __thread keyword. If TLS is available, jemalloc uses it for several purposes. --disable-cache-oblivious Disable cache-oblivious large allocation alignment for large allocation requests with no alignment constraints. If this feature is disabled, all large allocations are page-aligned as an implementation artifact, which can severely harm CPU cache utilization. However, the cache-oblivious layout comes at the cost of one extra page per large allocation, which in the most extreme case increases physical memory usage for the 16 KiB size class to 20 KiB. --disable-syscall Disable use of syscall(2) rather than {open,read,write,close}(2). This is intended as a workaround for systems that place security limitations on syscall(2). --with-xslroot= Specify where to find DocBook XSL stylesheets when building the documentation. --with-lg-page= Specify the base 2 log of the system page size. This option is only useful when cross compiling, since the configure script automatically determines the host's page size by default. --with-lg-page-sizes= Specify the comma-separated base 2 logs of the page sizes to support. This option may be useful when cross-compiling in combination with --with-lg-page, but its primary use case is for integration with FreeBSD's libc, wherein jemalloc is embedded. --with-lg-size-class-group= Specify the base 2 log of how many size classes to use for each doubling in size. By default jemalloc uses =2, which results in e.g. the following size classes: [...], 64, 80, 96, 112, 128, 160, [...] =3 results in e.g. the following size classes: [...], 64, 72, 80, 88, 96, 104, 112, 120, 128, 144, [...] The minimal =0 causes jemalloc to only provide size classes that are powers of 2: [...], 64, 128, 256, [...] An implementation detail currently limits the total number of small size classes to 255, and a compilation error will result if the you specify cannot be supported. The limit is roughly =4, depending on page size. --with-lg-quantum= Specify the base 2 log of the minimum allocation alignment. jemalloc needs to know the minimum alignment that meets the following C standard requirement (quoted from the April 12, 2011 draft of the C11 standard): The pointer returned if the allocation succeeds is suitably aligned so that it may be assigned to a pointer to any type of object with a fundamental alignment requirement and then used to access such an object or an array of such objects in the space allocated [...] This setting is architecture-specific, and although jemalloc includes known safe values for the most commonly used modern architectures, there is a wrinkle related to GNU libc (glibc) that may impact your choice of . On most modern architectures, this mandates 16-byte alignment (=4), but the glibc developers chose not to meet this requirement for performance reasons. An old discussion can be found at https://sourceware.org/bugzilla/show_bug.cgi?id=206 . Unlike glibc, jemalloc does follow the C standard by default (caveat: jemalloc technically cheats if --with-lg-tiny-min is smaller than --with-lg-quantum), but the fact that Linux systems already work around this allocator noncompliance means that it is generally safe in practice to let jemalloc's minimum alignment follow glibc's lead. If you specify --with-lg-quantum=3 during configuration, jemalloc will provide additional size classes that are not 16-byte-aligned (24, 40, and 56, assuming --with-lg-size-class-group=2). --with-lg-tiny-min= Specify the base 2 log of the minimum tiny size class to support. Tiny size classes are powers of 2 less than the quantum, and are only incorporated if is less than (see --with-lg-quantum). Tiny size classes technically violate the C standard requirement for minimum alignment, and crashes could conceivably result if the compiler were to generate instructions that made alignment assumptions, both because illegal instruction traps could result, and because accesses could straddle page boundaries and cause segmentation faults due to accessing unmapped addresses. The default of =3 works well in practice even on architectures that technically require 16-byte alignment, probably for the same reason --with-lg-quantum=3 works. Smaller tiny size classes can, and will, cause crashes (see https://bugzilla.mozilla.org/show_bug.cgi?id=691003 for an example). This option is rarely useful, and is mainly provided as documentation of a subtle implementation detail. If you do use this option, specify a value in [3, ..., ]. The following environment variables (not a definitive list) impact configure's behavior: CFLAGS="?" Pass these flags to the compiler. You probably shouldn't define this unless you know what you are doing. (Use EXTRA_CFLAGS instead.) EXTRA_CFLAGS="?" Append these flags to CFLAGS. This makes it possible to add flags such as -Werror, while allowing the configure script to determine what other flags are appropriate for the specified configuration. The configure script specifically checks whether an optimization flag (-O*) is specified in EXTRA_CFLAGS, and refrains from specifying an optimization level if it finds that one has already been specified. CPPFLAGS="?" Pass these flags to the C preprocessor. Note that CFLAGS is not passed to 'cpp' when 'configure' is looking for include files, so you must use CPPFLAGS instead if you need to help 'configure' find header files. LD_LIBRARY_PATH="?" 'ld' uses this colon-separated list to find libraries. LDFLAGS="?" Pass these flags when linking. PATH="?" 'configure' uses this to find programs. In some cases it may be necessary to work around configuration results that do not match reality. For example, Linux 4.5 added support for the MADV_FREE flag to madvise(2), which can cause problems if building on a host with MADV_FREE support and deploying to a target without. To work around this, use a cache file to override the relevant configuration variable defined in configure.ac, e.g.: echo "je_cv_madv_free=no" > config.cache && ./configure -C === Advanced compilation ======================================================= To build only parts of jemalloc, use the following targets: build_lib_shared build_lib_static build_lib build_doc_html build_doc_man build_doc To install only parts of jemalloc, use the following targets: install_bin install_include install_lib_shared install_lib_static install_lib install_doc_html install_doc_man install_doc To clean up build results to varying degrees, use the following make targets: clean distclean relclean === Advanced installation ====================================================== Optionally, define make variables when invoking make, including (not exclusively): INCLUDEDIR="?" Use this as the installation prefix for header files. LIBDIR="?" Use this as the installation prefix for libraries. MANDIR="?" Use this as the installation prefix for man pages. DESTDIR="?" Prepend DESTDIR to INCLUDEDIR, LIBDIR, DATADIR, and MANDIR. This is useful when installing to a different path than was specified via --prefix. CC="?" Use this to invoke the C compiler. CFLAGS="?" Pass these flags to the compiler. CPPFLAGS="?" Pass these flags to the C preprocessor. LDFLAGS="?" Pass these flags when linking. PATH="?" Use this to search for programs used during configuration and building. === Development ================================================================ If you intend to make non-trivial changes to jemalloc, use the 'autogen.sh' script rather than 'configure'. This re-generates 'configure', enables configuration dependency rules, and enables re-generation of automatically generated source files. The build system supports using an object directory separate from the source tree. For example, you can create an 'obj' directory, and from within that directory, issue configuration and build commands: autoconf mkdir obj cd obj ../configure --enable-autogen make === Documentation ============================================================== The manual page is generated in both html and roff formats. Any web browser can be used to view the html manual. The roff manual page can be formatted prior to installation via the following command: nroff -man -t doc/jemalloc.3