2.4.14pre3aa3 [was Re: VM test on 2.4.14pre3aa2 (compared to 2.4.14pre3aa1)]

Andrea Arcangeli
2001-10-29T03:57:59Z

On Mon, Oct 29, 2001 at 04:29:38AM +0100, Andrea Arcangeli wrote:
> On Mon, Oct 29, 2001 at 03:45:46AM +0100, Andrea Arcangeli wrote:
> > andrea@dev4-000:~> time ./mtest01 -b $[1024*1024*512] -w
> > PASS ... 536870912 bytes allocated.
> >
> > real 1m8.655s
> > user 0m9.370s
> > sys 0m2.250s
> > andrea@dev4-000:~>
>
> new exciting result on exactly the same test (4Ganon mem +512m swap,
> then started the bench):
>
> andrea@dev4-000:~> time ./mtest01 -b $[1024*1024*512] -w
> PASS ... 536870912 bytes allocated.
>
> real 0m40.473s
> user 0m9.290s
> sys 0m3.860s
> andrea@dev4-000:~>
>
> (mainline takes 1m 40s, 1 minute more for the same thing)
>
> I guess I cheated this time though :), see the _only_ change that I did to
> speedup from 68/69 seconds to exactly 40 seconds:

I uploaded a new 2.4.14pre3aa3 patckit with this and the other changes
included (again, under the rule that if this is wrong, MAP_SHARED was
just broken in first place). so you may want to give it a spin and see
if it goes better now. Of course also verify that you are doing a
reliable benchmark by always using -b option, or apply my patch to fix
the breakage of the -p option of the benchmark. Of course background
load matters too, so no updatedb or netscape or whatever, just mp3blast
and the benchmark with -b or with fixed -p, so we make sure to compare
apples to apples :). thanks!

(this isn't very well tested [my desktop still runs 2.4.14pre3aa2], but the
4-way 4G+2G at osdlab is under heavy swapout load and it doesn't complain yet

1 2 0 449880 4984 164 1644 7092 5760 7092 5760 371 528 25 2 73
1 2 0 449696 4724 164 1644 6912 6528 6912 6528 356 505 25 2 74
1 2 1 450656 5504 168 1644 6112 6912 6116 6912 329 452 25 2 73
1 2 1 450340 5248 164 1644 6924 6400 6924 6404 362 511 25 1 74
1 2 1 450248 5188 164 1644 6632 6400 6632 6400 350 492 25 1 74
1 2 1 449988 4900 164 1644 6544 6144 6544 6144 349 485 25 1 74
1 2 0 449340 4288 164 1644 6432 5600 6432 5600 345 479 25 2 73
1 2 2 450296 5432 168 1644 5632 6432 5636 6432 321 432 25 1 74
2 1 0 449924 4652 164 1644 6028 5360 6028 5364 330 440 19 8 73
1 2 0 450276 5264 164 1644 6036 6400 6036 6400 339 476 25 1 74
1 2 1 450744 5428 164 1644 6696 6928 6696 6928 356 496 25 1 74
1 2 1 450328 5244 164 1644 6848 6268 6848 6268 353 514 25 2 73
1 2 2 450156 4924 168 1644 6912 6652 6916 6652 358 510 25 1 74
1 2 0 449876 4608 164 1644 6180 5640 6180 5644 337 464 25 1 74
1 2 0 450152 4976 164 1644 6284 6516 6284 6516 338 468 25 2 73
1 2 1 451188 5184 164 1648 6560 6624 6560 6624 347 474 25 1 74
1 2 1 448620 3480 164 1644 6748 4780 6748 4780 353 481 25 18 57
1 2 0 449520 4348 164 1644 5868 6528 5868 6528 330 450 25 0 75
1 2 0 450460 5012 164 1644 6240 7016 6240 7016 343 459 25 1 74
1 2 0 450524 5028 164 1644 6616 6552 6616 6552 353 484 25 1 74
1 2 0 449928 4620 164 1644 6952 6136 6952 6136 365 511 25 2 73
1 2 0 450036 4936 164 1644 6336 6408 6336 6408 341 460 25 3 72
1 2 1 450560 5156 168 1644 6172 6400 6176 6400 335 466 25 1 74

again the sane 12/13mbyte/sec of bandwith, instead of the previous 7mbyte/sec)

oom mmap001 failures should be cured (untested though), as said the bug was
pretty obvious after I got the report, thanks!

ftp://ftp.us.kernel.org/pub/linux/kernel/people/andrea/kernels/v2.4/2.4.14pre3aa3.bz2
ftp://ftp.us.kernel.org/pub/linux/kernel/people/andrea/kernels/v2.4/2.4.14pre3aa3/

Only in 2.4.14pre3aa2: 00_files_struct_rcu-2.4.10-04-3
Only in 2.4.14pre3aa3: 00_files_struct_rcu-2.4.10-04-4

Fixed missing var initialization.

Only in 2.4.14pre3aa2: 10_vm-6
Only in 2.4.14pre3aa3: 10_vm-7
Only in 2.4.14pre3aa3: 10_vm-7.1

Further vm changes, should fix mmap001 failures and improve
swapout performance.

Only in 2.4.14pre3aa3: 52_u64-1

Minor compile fix for uml.

BTW, you can still tweak the /proc/sys/vm/vm_* parameters. there's the
updated commentary in mm/vmscan.c. default values should be sane. As usual an
unit change isn't going to make relevant differences, those numbers doesn't
need to be perfect.

Andrea