Con Kolivas wrote:
>
> Here are contest 0.51 benchmarks for 2.5.44-mm1 with shared pagetables enabled:
>
> noload:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [2] 73.4 93 0 0 1.03
> 2.5.44 [3] 74.6 93 0 0 1.04
> 2.5.44-mm1 [3] 75.0 93 0 0 1.05
Not really sure what's going on here. I hope you don't have one of
those CPUs which magically slows down when it gets hot.
I tried it:
2.4.19
make -j6 bzImage 408.52s user 27.74s system 369% cpu 1:58.19 total
make -j6 bzImage 406.61s user 26.79s system 376% cpu 1:55.24 total
slightly faster on the second run, more stuff was in cache.
2.5.44-mm2ish
1st make -j6 bzImage 417.03s user 34.95s system 376% cpu 2:00.14 total
2nd make -j6 bzImage 414.78s user 33.08s system 375% cpu 1:59.17 total
bit slower. So let's set HZ to 100:
2.5.44-mm2ish HZ=100
make -j6 bzImage 406.67s user 32.17s system 370% cpu 1:58.33 total
make -j6 bzImage 404.79s user 30.66s system 377% cpu 1:55.27 total
> process_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [2] 105.8 71 44 31 1.48
> 2.5.44 [3] 90.9 76 32 26 1.27
> 2.5.44-mm1 [3] 191.5 36 168 64 2.68
>
> These were all checked to ensure it was not one pathological run making the
> value high. The range was 190.6->192.7.
That'll be the pipe change I guess.
> ctar_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [1] 92.3 82 1 5 1.29
> 2.5.44 [3] 97.7 80 1 6 1.37
> 2.5.44-mm1 [3] 99.2 78 1 6 1.39
>
> xtar_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [2] 171.0 45 2 8 2.39
> 2.5.44 [3] 117.0 65 1 7 1.64
> 2.5.44-mm1 [3] 156.2 49 2 7 2.19
>
> io_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [2] 301.1 26 21 11 4.22
> 2.5.44 [3] 873.8 9 69 12 12.24
> 2.5.44-mm1 [3] 347.3 22 35 15 4.86
>
> read_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [1] 105.7 73 6 4 1.48
> 2.5.44 [3] 110.8 68 6 3 1.55
> 2.5.44-mm1 [3] 110.5 69 7 3 1.55
>
> list_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [1] 98.9 72 1 23 1.39
> 2.5.44 [3] 99.1 71 1 21 1.39
> 2.5.44-mm1 [3] 96.5 74 1 22 1.35
>
> mem_load:
> Kernel [runs] Time CPU% Loads LCPU% Ratio
> 2.5.43-mm2 [2] 106.5 69 27 2 1.49
> 2.5.44 [3] 114.3 67 30 2 1.60
> 2.5.44-mm1 [3] 159.7 47 38 2 2.24
>
> Notably different results in many places. This is a similar pattern to the last
> time I enabled shared pagetables. I haven't had the time to try without it
> enabled yet.
>
It's not shared pagetables. It's lots of other things though. Mainly
the IO scheduler.
Almost all of your tests are testing reads competing with reads, and
reads competing with writes. We fiddled with that pretty fundamentally.
The -mm patches have fifo_batch at 16 rather than 32, which explains
most of the above differences. That change will cause an overall
reduction in throughput for these sorts of loads.
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This archive was generated by hypermail 2b29 : Wed Oct 23 2002 - 22:00:51 EST