Author: alc Date: Tue Jul 31 17:41:48 2018 New Revision: 336984 URL: https://svnweb.freebsd.org/changeset/base/336984
Log: Allow vm object coalescing to occur in the midst of a vm object when the OBJ_ONEMAPPING flag is set. In other words, allow recycling of existing but unused subranges of a vm object when the OBJ_ONEMAPPING flag is set. Such situations are increasingly common with jemalloc >= 5.0. This change has the expected effect of reducing the number of vm map entry and object allocations and increasing the number of superpage promotions. Reviewed by: kib, markj Tested by: pho MFC after: 6 weeks Differential Revision: https://reviews.freebsd.org/D16501 Modified: head/sys/vm/vm_object.c Modified: head/sys/vm/vm_object.c ============================================================================== --- head/sys/vm/vm_object.c Tue Jul 31 17:18:58 2018 (r336983) +++ head/sys/vm/vm_object.c Tue Jul 31 17:41:48 2018 (r336984) @@ -2142,8 +2142,9 @@ vm_object_coalesce(vm_object_t prev_object, vm_ooffset next_size >>= PAGE_SHIFT; next_pindex = OFF_TO_IDX(prev_offset) + prev_size; - if ((prev_object->ref_count > 1) && - (prev_object->size != next_pindex)) { + if (prev_object->ref_count > 1 && + prev_object->size != next_pindex && + (prev_object->flags & OBJ_ONEMAPPING) == 0) { VM_OBJECT_WUNLOCK(prev_object); return (FALSE); } _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
