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sdm660-common: gps: Localise NTP to improve GPS TTFF

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Testing response times to time.android.com from around the globe reveals
in ms:-

Europe			 <30
Middle East		 <68
North America		<150
Johannesburg		 183
Buenos Aires		 220
Tokyo			 226
Sydney			 276
Hong Kong		 285
Brisbane		 295
Mumbai			 349
Beijing			4691
Shanghai		4906
Russia			 n/a

Whilst time.android.com is NOT used for GPS NTP, North American time servers
are, by specifying north-america.pool.ntp.org as default in the framework,
to align with pixel devices.  I am assuming similar response times to these
servers from around the world.

Great for North America and it appears Europe but it does not address the
global issue. Also, the pool.ntp.org project forbids both hardware and
software vendors from using these default zone names.
http://www.pool.ntp.org/en/vendors.html

It makes sense, therefore, to leverage the ntp.org's existing 'android' vendor
name to make the default ntp server for GPS purposes:
1.android.pool.ntp.org this will return a random but accurate NTP server in
close geopraphic proximity to the device.

Testing on my own build in the UK seems to improve hot and cold TTFF
considerably.

Change-Id: I144af45757efa35b32daf034eece6e046d2bde79
This commit is contained in:
–Gareth Kitchen 2021-04-25 01:03:07 +02:00 committed by OdSazib
parent 83706265c1
commit 7a54003bff
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GPG key ID: B678DBD07079B021
1 changed files with 1 additions and 1 deletions
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2
gps/etc/gps.conf
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@ -4,7 +4,7 @@
ERR_ESTIMATE=0 ERR_ESTIMATE=0
#NTP server #NTP server
NTP_SERVER=time.xtracloud.net NTP_SERVER=1.android.pool.ntp.org
#XTRA CA path #XTRA CA path
XTRA_CA_PATH=/usr/lib/ssl-1.1/certs XTRA_CA_PATH=/usr/lib/ssl-1.1/certs