See: http://blogs.testbit.eu/timj/2005/12/02/02122005-landing-g_slice_new/ (page moved)
I finally managed to finish up the new g_slice_*() allocator for GLib CVS and commit it. For most platforms, it should be a lot faster than malloc(), and on my machine it saves 20-30% in performance over allocating with mem-chunks. But most importantly, it does share equally sized chunks across a program, which mem-chunks didn’t, so they opened up several independent heaps of equally sized chunks, scattered all over the program and causing large wastage.
I would like to thank Matthias Clasen for an initial version of the magazine cache and Stefan Westerfeld for helping me with optimizing the common code paths.