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charset=utf-8 Content-Disposition: inline X-Rspamd-Queue-Id: 10482C000F X-Rspam-User: X-Stat-Signature: urmqz1gnex1rwabxskzqdmdkfde65jkq X-Rspamd-Server: rspam09 X-HE-Tag: 1755115590-736677 X-HE-Meta: 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 rPFoP/K5 dL7lgrlZ3REJ3lWujo+7qm47M3rsha2JysfVFVQpBLJXIQywvGHH6hcsYxexCJHjwsw6h6N35Ve4QD2ptRNdymM2S+JZSlSQYyQDCJueWnKqtHwqf8ainwWWecwPXJcfnVQiUdWdt6aZDwo6VljpQwMlVyQszT0CrEwJ6XIeqjJ7pBqgmZfFda1jMKGmGkzkgkGLInZkna/VXV9wkVXd1mpnizmIxQTAQQODlOxrjNvPy+cGi3Jh9CkknHZiaSgecXic2oVLR11WviGHe9T1ABH8zT7xuE9O6R/hTJqXc9AzgvuXxpmDq/kA0ANBPODdNrRN4KSVlJ8IwhxEi0cHsUe1fSx0T3AUdRvJop9Qu8UcLmTU8BAb1p88prKIo+sf+RNaZf01SxChtxZpcn02JRtGawsRrIyms6ymJaMNdXtuQ85Bn3kQCdTf7k/aCezfpdcbK2+WA8OK5j368o1IGjkrJmSdYY84JYEYyVUCtYKGl3FmtKH4QsKcCTA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Aug 13, 2025 at 12:30:24PM -0700, Lokesh Gidra wrote: > MOVE ioctl's runtime is dominated by TLB-flush cost, which is required > for moving present pages. Mitigate this cost by opportunistically > batching present contiguous pages for TLB flushing. > > Without batching, in our testing on an arm64 Android device with UFFD GC, > which uses MOVE ioctl for compaction, we observed that out of the total > time spent in move_pages_pte(), over 40% is in ptep_clear_flush(), and > ~20% in vm_normal_folio(). > > With batching, the proportion of vm_normal_folio() increases to over > 70% of move_pages_pte() without any changes to vm_normal_folio(). > Furthermore, time spent within move_pages_pte() is only ~20%, which > includes TLB-flush overhead. > > When the GC intensive benchmark, which was used to gather the above > numbers, is run on cuttlefish (qemu android instance on x86_64), the > completion time of the benchmark went down from ~45mins to ~20mins. > > Furthermore, system_server, one of the most performance critical system > processes on android, saw over 50% reduction in GC compaction time on an > arm64 android device. > > Cc: Suren Baghdasaryan > Cc: Kalesh Singh > Cc: Barry Song > Cc: David Hildenbrand > Cc: Peter Xu > Signed-off-by: Lokesh Gidra Acked-by: Peter Xu -- Peter Xu