On 28/02/13 12:35, Jan Beulich wrote: >>>> On 28.02.13 at 12:25, Roger Pau Monné<roger....@citrix.com> wrote: >> This is the expanded graph that also contains indirect descriptors >> without persistent grants: >> >> http://xenbits.xen.org/people/royger/plot_indirect_nopers.png > > Thanks. Interesting - this suggests an unexpectedly high hit rate.
This graph is using the default values, so we are persistently mapping 1024 grants of the possible 2080 that could be used by blkfront ((64 segments + 1 indirect gref) * 32 = 2080). blkfront stores grants using a stack, so it should try to reuse the same grants as much as possible. On the other hand, blkback cleans unused grants periodically, to try to have the most commonly used blkfront grants mapped. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
