On Sun, 26 Feb 2023 12:12:59 +0800 Hillf Danton wrote:
> On Sun, 26 Feb 2023 02:34:05 +0000 Matthew Wilcox <willy@xxxxxxxxxxxxx>
> > On Sun, Feb 26, 2023 at 09:30:31AM +0800, Hillf Danton wrote:
> > > On Wed, Feb 22, 2023 at 04:55:20PM -0700, Yu Zhao wrote:
> > > > Currently anonymous folios only support two orders: 0 and the PMD
> > > > order. Flexible orders for anonymous folios can resist both internal
> > > > or external fragmentations when the PMD order is too underutilized or
> > > > costly to allocate. Flexible orders can also leverage the TLB
> > > > coalescing feature, .e.g., order 3 for AMD and order 4 for ARM CPUs.
> > > >
> > > > Discussion points:
> > > > 1. The page fault path: determining the best order and the fallback policy.
> > > > 2. The reclaim path: detecting the utilization and the splitting policy.
> > > > 3. The refcount and the mapcount models, e.g., reuse the PMD-mapped
> > > > THP model or not.
> > > > 4. The splitting, and the collapsing if needed.
> > > > 5. Other paths: COW, GUP, madvise(), mprotect(), page migration, etc.
> > >
> > > 6. Given the number of TLB is farrr less than the number of pages,
> > > what workload prefers MADV_ORDER6 over MADV_HUGEPAGE for instance?
7. Given p4d_t, is 2023-25 the right time to add the PUD order?
> >
> > Many. https://lore.kernel.org/linux-mm/Y%2FWRlX+MkmxelNbg@xxxxxxxxxxxxxxxxxxxx/
>
> Which one, supposedly given Apache Spark, MariaDB, Memcached, MongoDB,
> Apache Cassandra, Apache Hadoop, PostgreSQL and Redis to ease the anwser?
