On Thu, 13 Dec 2018 13:42:24 +0100
Paolo Valente <paolo.valente(a)linaro.org> wrote:
To test the behavior of your system, why don't you check, e.g.,
how
long it takes to start an application while there is some background
I/O?
A super quick way to do this is
git clone
https://github.com/Algodev-github/S
cd S/comm_startup_lat
sudo ./comm_startup_lat.sh <scheduler-you-want-to-test> 5 5 seq 3
"replay-startup-io gnometerm"
The last command line
- starts the reading of 5 files plus the writing of 5 other files
- replays, for three times, the I/O that gnome terminal does while;
starting up (if you want I can tell you how to change the last
command line so as to execute the original application, but you would
get the same results);
- for each attempt, measures how long this start-up I/O takes to
complete.
Results for cfq and noop, haven't enabled bfq yet. I interpret these
as showing that cfq was a large improvement for all categories except
write throughput, where it actually degraded performance.
cfq
Latency statistics:
min max avg std_dev conf99%
22.142 27.157 24.1967 2.6273 52.5604
Aggregated throughput:
min max avg std_dev conf99%
67.29 139.74 105.491 19.245 39.7628
Read throughput:
min max avg std_dev conf99%
51.73 135.67 102.402 21.3985 44.2123
Write throughput:
min max avg std_dev conf99%
0.01 46.29 3.08857 8.37179 17.2972
noop
Latency statistics:
min max avg std_dev conf99%
40.861 42.021 41.3637 0.595266 11.9086
Aggregated throughput:
min max avg std_dev conf99%
45.66 72.89 55.9847 5.99054 9.87365
Read throughput:
min max avg std_dev conf99%
41.69 70.85 51.9495 6.02467 9.9299
Write throughput:
min max avg std_dev conf99%
0 7.9 4.03527 1.62392 2.67656