To make apt works the way I want, I add this file into /etc/apt/apt.conf.d/. Uses 99 prefix to override other apt.conf with lower prefix.
99local:
Acquire {
Queue-Mode "host";
Retries "990";
http {
/* Proxy "http://127.0.0.1:3129"; */
Timeout "67";
Pipeline-Depth "5";
};
};
APT {
Default-Release "testing";
/* Cache-Limit "33554432"; */
Periodic {
Update-Package-Lists "1";
AutocleanInterval "1";
Download-Upgradeable-Packages "0";
};
Archives {
MinAge "0";
MaxAge "0";
MaxSize "0";
};
};
DPkg::Post-Invoke { "if [ -x /usr/sbin/update-dlocatedb ]; then update-dlocatedb; fi"; };