Re: [PATCH] remove useless highmem bounce from loop/cryptoloop

[Ben Slusky]

My astute and obviously flawless technical analysis seems to be at odds
with the benchmarks, which show reads completed in half the time with
Andrew's patches as with mine. Writes are a little slower tho'.

Results attached.

-- 
Ben Slusky                      | Some drink from the Fountain
sluskyb@xxxxxxxxxxxxxx          | of Knowledge... Others just
sluskyb@xxxxxxxxxx              | gargle. ...And some pee in it.
PGP keyID ADA44B3B              |               -Dave Aronson

Write test:
time sh -c 'dd if=/dev/urandom of=testfoo bs=32k count=5000 conv=notrunc; sync'
0.03user 131.66system 2:26.62elapsed 89%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 133.35system 2:34.15elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 133.35system 2:30.97elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 131.64system 2:29.25elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 128.32system 2:26.25elapsed 87%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 130.65system 2:28.31elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 128.49system 2:25.50elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 128.48system 2:26.03elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 128.63system 2:25.96elapsed 88%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 127.40system 2:24.91elapsed 87%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps

Read test:
time dd if=testfoo of=/dev/null bs=32k
0.04user 1.45system 0:37.20elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.45system 0:37.07elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.42system 0:37.10elapsed 3%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.46system 0:37.12elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.44system 0:37.13elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.43system 0:37.10elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.44system 0:37.23elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.43system 0:37.07elapsed 3%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.44system 0:37.13elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.43system 0:37.12elapsed 4%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps

Read/Write test:
time sh -c 'tar xjf src/linux-2.6.0-test1.tar.bz2; sync'
58.32user 20.09system 1:58.83elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
58.86user 18.22system 1:57.10elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
59.00user 17.58system 1:56.83elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
59.28user 17.49system 1:57.10elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
58.84user 18.19system 1:56.98elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
58.82user 17.74system 1:56.15elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
58.89user 17.71system 1:57.00elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
59.07user 17.82system 1:57.33elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
59.36user 18.29system 1:57.05elapsed 66%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
59.14user 17.59system 1:56.91elapsed 65%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
Write test:
time sh -c 'dd if=/dev/urandom of=testfoo bs=32k count=5000 conv=notrunc; sync'
0.05user 131.32system 2:36.10elapsed 84%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 137.84system 2:40.38elapsed 85%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.02user 137.72system 2:40.32elapsed 85%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 137.09system 2:39.38elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 136.31system 2:38.62elapsed 85%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 135.40system 2:37.26elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 133.00system 2:33.92elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.03user 134.56system 2:35.92elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 133.76system 2:35.15elapsed 86%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (439major+100minor)pagefaults 0swaps
0.04user 133.41system 2:35.23elapsed 85%CPU (0avgtext+0avgdata 0maxresident)k

Read test:
time dd if=testfoo of=/dev/null bs=32k
0.03user 1.37system 0:18.46elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.37system 0:18.20elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.32system 0:17.85elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.30system 0:17.66elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.31system 0:17.67elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.30system 0:17.67elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.05user 1.27system 0:17.65elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.30system 0:17.64elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.35system 0:18.09elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps
0.04user 1.38system 0:18.42elapsed 7%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (364major+75minor)pagefaults 0swaps

Read/Write test:
time sh -c 'tar xjf src/linux-2.6.0-test1.tar.bz2; sync'
60.41user 13.18system 1:57.85elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.37user 13.26system 1:58.74elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.59user 13.30system 1:57.83elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.53user 13.25system 1:58.48elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.41user 13.29system 1:58.47elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.46user 13.33system 1:57.36elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.44user 13.07system 1:59.50elapsed 61%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.14user 13.12system 1:58.03elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.28user 13.18system 1:58.58elapsed 61%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps
60.44user 13.32system 1:58.93elapsed 62%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (623major+1033minor)pagefaults 0swaps