tcmalloc is a memory allocation library provided by Google that works well with long running highly concurrent programs in SWI-Prolog, notably reducing the required memory resources.

Consequences

If SWI-Prolog is not compiled with tcmalloc support

1. it does not support malloc_property/1, set_malloc/1 and heapused, memory and core keys of statistics/2.
2. The total memory footprint can be significantly higher than when using the system's default memory allocator. This depends on the OS and SWI-Prolog workload though.

Solutions

• If a binary distribution starts, but check_installation/0 reports tcmalloc as missing, you should contact the packager of the distribution and point at this page.
• If you built from source, make sure the tcmalloc library is installed. The package is typically called something including perftools, i.e., libgoogle-perftools-dev (Debian), gperftools-devel (Redhat), gperftools (Macports). It must provide the library libtcmalloc_minimal. The header files are not required.