GCs that run somehow in background and are not primarily trigerred by allocation are quite rare, IIRC all GCs shipped with LVM are also only triggered by alloca

GCs that run somehow in background and are not primarily trigerred by allocation are quite rare, IIRC all GCs shipped with LVM are also only triggered by allocation. In fact only two production cases of primarily background GCs that I can think of at the moment are some Lisp Machines (IIRC LMI) with HW assisted incremental copying GC and Azul's GC, which uses quite similar approach.