On Mon, 16 Apr 2018, Mikulas Patocka wrote: > dm-bufio deals gracefully with allocation failure, because it preallocates > some buffers with vmalloc, but other subsystems may not deal with it and > they cound return ENOMEM randomly or misbehave in other ways. So, the > "SLAB_MINIMIZE_WASTE" flag is also saying that the allocation may fail and > the caller is prepared to deal with it. > > The slub subsystem does actual fallback to low-order when the allocation > fails (it allows different order for each slab in the same cache), but > slab doesn't fallback and you get NULL if higher-order allocation fails. > So, SLAB_MINIMIZE_WASTE is needed for slab because it will just randomly > fail with higher order. Fix Slab instead of adding a flag that is only useful for one allocator? -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
