|
This makes the Date plugin approximately twice as fast, and makes xmobar
up to about 5–10 % faster if Date is the only active plugin. (If more
expensive plugins like Network or MultiCpu are used, it doesn't make any
measurable difference.)
Micro-benchmark results on my HW:
Date Benchmarks/Date mean 2.833 μs ( +- 16.08 ns )
Date Benchmarks/DateZonedTime mean 5.020 μs ( +- 32.91 ns )
Date Benchmarks/DateWithTimeZone mean 2.827 μs ( +- 20.52 ns )
(DateZonedTime is the original implementation and DateWithTimeZone is
the implementation we had since 0.34 which never refreshes timezone.)
Real-life measurements (done overnight on an idle laptop, with all
measured xmobars running in parallel to ensure comparable conditions;
xmobars configured to only display date and with rate 10 — once per
second):
$ time timeout 6h xmobar .xmobarrc-DateZonedTime
real 360m0,010s
user 0m9,867s
sys 0m4,644s
(9.867 + 4.644) / (360 * 60) = 0.000672
$ time timeout 6h xmobar .xmobarrc-Date
real 360m0,008s
user 0m9,535s
sys 0m4,327s
(9.535 + 4.327) / (360 * 60) = 0.000642
$ time timeout 6h xmobar .xmobarrc-Date-10m
real 360m0,010s
user 0m9,780s
sys 0m4,215s
(9.780 + 4.215) / (360 * 60) = 0.000648
$ time timeout 6h xmobar .xmobarrc-DateWithTimeZone
real 360m0,006s
user 0m9,658s
sys 0m4,166s
(9.658 + 4.166) / (360 * 60) = 0.000640
(.xmobarrc-Date-10m is the proposed implementation, but with timezone
refresh every 10 minutes instead of every 1 minute)
Interpretation of these results:
* refreshing xmobar with just date takes around 650 μs
* that is xmobar with just date uses around 0.065 % of CPU time
* refreshing timezone takes additional cca 30 μs
When we only refresh timezone once a minute, these 30 μs become 0.5 μs
amortized, and that should be acceptable to even the most dedicated
perfectionist :-)
Fixes: a58e32f7c8af ("Revert "Optimize date plugin"")
Fixes: 878db3908060 ("Optimize date plugin")
Co-authored-by: Sibi Prabakaran <sibi@psibi.in>
|
