As segwit is active on testnet, blocks will only be downloaded from NODE_WITNESS peers. Though, exactly those peers are disconnected after `BLOCK_STALLING_TIMEOUT = 2` seconds. I am running master (6e6ab2c)

This behavior is consistent across restarts. Sample [debug.log](http://pastebin.ubuntu.com/23058327/) and [getchaintips](http://pastebin.ubuntu.com/23058325/).

It is possible that I shot my own foot at some point, but it seemed smelly enough to create an issue.

break;
            }
            
            
            const int nPrunedBlocksLikelyToHave = MIN_BLOCKS_TO_KEEP - 3600 / chainparams.GetConsensus().nPowTargetSpacing;
            if (fPruneMode && (!(pindex->nStatus & BLOCK_HAVE_DATA) || pindex->nHeight <= chainActive.Tip()->nHeight - nPrunedBlocksLikelyToHave))
            {
                LogPrint("net", " getblocks stopping, pruned or too old block at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                break;
            }
            pfrom->PushInventory(CInv(MSG_BLOCK, pindex->GetBlockHash()));
            if (--nLimit <= 0)
            {
                
                
                LogPrint("net", "  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
                pfrom->hashContinue = pindex->GetBlockHash();
                break;
            }
        }
    }
    else if (strCommand == NetMsgType::GETBLOCKTXN)
    {
        BlockTransactionsRequest req;
        vRecv >> req;
        BlockMap::iterator it = mapBlockIndex.find(req.blockhash);
        if (it == mapBlockIndex.end() || !(it->second->nStatus & BLOCK_HAVE_DATA)) {
            LogPrintf("Peer %d sent us a getblocktxn for a block we don't have", pfrom->id);
            return true;
        }