On Fri, May 17, 2019 at 5:26 AM Chapman Flack <c...@anastigmatix.net> wrote: > On 5/16/19 12:24 PM, Albert Cervera i Areny wrote: > > Missatge de Thomas Munro <thomas.mu...@gmail.com> del dia dj., 16 de > > maig 2019 a les 13:09: > >> With all three mitigations activated, my little dev machine has gone > >> from being able to do ~11.8 million baseline syscalls per second to > > > > Did you mean "1.8"? > > Not in what I thought I saw: > > >> ~1.6 million, or ~1.4 million ... > >> > >> PTI IBRS MDS=off MDS=VERW MDS=AVX > >> ===== ===== ======== ======== ======== > >> off off 11798658 4764159 3274043 > ^^^^^^^^ > >> off on 2652564 1941606 1655356 > >> on off 4973053 2932906 2339779 > >> on on 1988527 1556922 1378798 > ^^^^^^^ ^^^^^^^
Right. Actually it's worse than that -- after I posted I realised that I had some debug stuff enabled in my kernel that was slowing things down a bit, so I reran the tests overnight with a production kernel and here is what I see this morning. It's actually ~17.8 million syscalls/sec -> ~1.7 million syscalls/sec, if you go from all mitigations off to all mitigations on, or -> ~3.2 million for just PTI + MDS. And the loss of TPS is ~5% for the case I was most interested in, just turning on MDS=VERW if you already had PTI on and IBRS off. Raw getuid() syscalls per second: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 17771744 5372032 3575035 off on 3060923 2166527 1817052 on off 5622591 3150883 2463934 on on 2213190 1687748 1475605 pgbench read-only transactions per second, 1 client thread: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 22414 22103 21571 off on 21298 20817 20418 on off 22473 22080 21550 on on 21286 20850 20386 pgbench -M prepared read-only transactions per second, 1 client thread: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 43508 42476 41123 off on 40729 39483 38555 on off 44110 42989 42012 on on 41143 39990 38798 pgbench -M prepared read-only transactions per second, 4 client threads: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 100735 97689 96662 off on 80142 77804 77064 on off 100540 97010 95827 on on 79492 76976 76226 pgbench -M prepared read-only transactions per second, 16 client threads: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 161015 152978 152556 off on 145605 139438 139179 on off 155359 147691 146987 on on 140976 134978 134177 pgbench -M prepared read-only transactions per second, 16 client threads: PTI IBRS MDS=off MDS=VERW MDS=AVX ===== ===== ======== ======== ======== off off 157986 150132 149436 off on 142618 136220 135901 on off 153482 146214 145839 on on 138650 133074 132142 -- Thomas Munro https://enterprisedb.com
