After starting from command line bitocoind, it can require minutes to have bitocoind to be real responsive, for example:
`$ ./bitcoin-cli stop`
`error: {"code":-28,"message":"Activating best chain..."}`

In such situation, I had sometimes to "kill -9" bitcoind to stop it.
I would like to be able to stop bitcoind in clean way.

p.s.:
`$ uname -a`
`Darwin isghe.local 14.4.0 Darwin Kernel Version 14.4.0: Thu May 28 11:35:04 PDT 2015; root:xnu-2782.30.5~1/RELEASE_X86_64 x86_64`

FLUSH_STATE_NONE,
    FLUSH_STATE_IF_NEEDED,
    FLUSH_STATE_PERIODIC,
    FLUSH_STATE_ALWAYS
};
/**
 * Update the on-disk chain state.
 * The caches and indexes are flushed depending on the mode we're called with
 * if they're too large, if it's been a while since the last write,
 * or always and in all cases if we're in prune mode and are deleting files.
 */
bool static FlushStateToDisk(CValidationState &state, FlushStateMode mode) {
    const CChainParams& chainparams = Params();
    LOCK2(cs_main, cs_LastBlockFile);
    static int64_t nLastWrite = 0;
    static int64_t nLastFlush = 0;
    static int64_t nLastSetChain = 0;
    std::set<int> setFilesToPrune;
    bool fFlushForPrune = false;
    try {
    if (fPruneMode && fCheckForPruning && !fReindex) {
        FindFilesToPrune(setFilesToPrune, chainparams.PruneAfterHeight());