It takes from 5 (shortest) to almost 40 (longest) minutes for bitcoin-cli gettxoutsetinfo
to return an empty dict. I noticed this first whilst configuring the Statoshi branch of Bitcoin Core, but went back to install Bitcoin Core (git clone -b v0.11.2 https://github.com/bitcoin/bitcoin.git) to find the same results.
020:10 pi@raspinode:~/bin/bitcoin.orig $ bitcoin-cli gettxoutsetinfo
1{
2}
320:12 pi@raspinode:~/bin/bitcoin.orig $ bitcoin-cli getinfo
4{
5 "version" : 110200,
6 "protocolversion" : 70002,
7 "blocks" : 393193,
8 "timeoffset" : 0,
9 "connections" : 12,
10 "proxy" : "",
11 "difficulty" : 113354299801.47113037,
12 "testnet" : false,
13 "relayfee" : 0.00005000,
14 "errors" : ""
15}
1620:17 pi@raspinode:~/bin/bitcoin.orig $
Raspberry Pi 2 - 1GB memory - 4 core CPU 900MHz - Blockchain on SanDisk Ultra Android microSDXC 128GB up to 80 MB/Sec Class 10
All other RPC calls through bitcoin-cli are answered promptly and correctly. See also issue on jlopp/statoshi https://github.com/jlopp/statoshi/issues/19#issuecomment-171350739