On 2018-11-06 15:34:55 [-0600], Grygorii Strashko wrote: > Hi All, Hi, > Do anybody tried to use ARM64 RT with 76K pages enabled?
75 would be an off by one but this :) > My attempt shows that enabling CONFIG_ARM64_64K_PAGES=y increases latencies > by ~30% > > cyclictest -n -m -Sp98 -q -D2m with CONFIG_ARM64_64K_PAGES=y > > > T: 0 ( 772) P:98 I:1000 C: 120000 Min: 7 Act: 13 Avg: 10 Max: > 85 > T: 1 ( 773) P:98 I:1500 C: 79998 Min: 7 Act: 13 Avg: 10 Max: > 71 > T: 2 ( 774) P:98 I:2000 C: 59997 Min: 7 Act: 11 Avg: 11 Max: > 64 > T: 3 ( 775) P:98 I:2500 C: 47996 Min: 7 Act: 14 Avg: 12 Max: > 66 > > > cyclictest -n -m -Sp98 -q -D2m with CONFIG_ARM64_64K_PAGES=n > > > T: 0 ( 697) P:98 I:1000 C: 120000 Min: 7 Act: 10 Avg: 9 Max: > 38 > T: 1 ( 698) P:98 I:1500 C: 79987 Min: 7 Act: 10 Avg: 10 Max: > 32 > T: 2 ( 699) P:98 I:2000 C: 59981 Min: 7 Act: 14 Avg: 11 Max: > 46 > T: 3 ( 700) P:98 I:2500 C: 47977 Min: 6 Act: 11 Avg: 10 Max: > 45 So this is an idle system? The Kconfig help says "faster TLB lookup". Interesting. Are the 16k pages in between (latency wise) by any chance? > -- > regards, > -grygorii Sebastian
