Commit graph

3 commits

Author SHA1 Message Date
Elliott Hughes
31fc69f67f Fix tzalloc(nullptr) and add a test.
This works (by reading /etc/localtime) on NetBSD, but not on Android
since we have no such file. Fix that by using our equivalent system
property instead.

Also s/time zone/timezone/ in documentation and comments. We've always
been inconsistent about this (as is upstream in code comments and
documentation) but it seems especially odd now we expose a _type_ that
spells it "timezone" to talk of "time zone" even as we're describing
that type and its associated functions.

Bug: https://github.com/chronotope/chrono/issues/499
Test: treehugger
Change-Id: I142995a3ab4deff1073a0aa9e63ce8eac850b93d
2023-06-22 09:51:01 -07:00
Maciej Żenczykowski
eb76022557 removing ro.kernel.ebpf.supported property
Android S devices must support eBPF.

Test: builds, atest, TreeHugger
Bug: 167500195
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I84a8d00f786fca8113dd3d555af279a1029f66f2
2021-01-11 18:10:58 -08:00
Tom Cherry
a5744e213f Add benchmark for property mapping
This benchmarks mapping property prefixes to property contexts with
two algorithms: the 'Legacy' method used before Android P and the
'Trie' used afterwards (the code in this directory).

It uses input mappings from both Oreo and the latest in AOSP ('S').
Note that there is nearly a 10x increase in the number of mappings in
S as there was in Oreo, which was predicted when the trie was
designed.

Results on cuttlefish:
-----------------------------------------------------------
Benchmark                 Time             CPU   Iterations
-----------------------------------------------------------
LegacyLookupOreo     683576 ns       673538 ns         1060
LegacyLookupS       5683109 ns      5596982 ns          124
TrieLookupOreo       299851 ns       295696 ns         2378
TrieLookupS          584831 ns       576801 ns         1204

The results show that the legacy look up uses 8.3x more CPU time to
handle the number of mappings added through S, whereas the Trie lookup
uses less than 2x more CPU time, showing that the trie scales better
with added mappings.

Test: run this benchmark
Change-Id: I35c3aa4429f049e327a891f9cbe1901d8855d7ba
2020-09-02 16:12:21 +00:00