LINUX and possibly other OS will over-commit memory. I.e. actual memory pages allocation will be deferred to the time of the first access. As a result, the application may simply segfault later.
Therefore, ensure that the membuffer creation actually allocates memory pages. Also, free the whole cache memory if allocation of some parts failed. Continue with the cache disabled in that case.
* subversion/libsvn_fs_util/caching.c (svn_fs__get_global_membuffer_cache): if cache creation fails, actually free the previously allocated memory * subversion/libsvn_subr/cache-membuffer.c (secure_aligned_pcalloc): replacement for apr_pcalloc that will not crash upon OOM (svn_cache__membuffer_cache_create): ensure that memory gets actually allocated despite of overcommitment by the OS; don't try to continue upon OOM