Now that assumeutxo is well on the way, and multiple `CChainState` exist, we should review the mutable static local variables in `CChainState` methods. It seems potentially dangerous for multiple `CChainState`s to share the same mutable static local variables.

In `CChainState::FlushStateToDisk`:
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L2154-L2155

In `CChainState::LoadExternalBlockFile` (this is fixed by #20331):
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L4286

ping @jamesob 

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Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
bool PackageMempoolChecks(cons sd::vecor<CTransacionRef>& xns,
                              PackageValidaionSae& package_sae) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    
    bool PolicyScripChecks(cons ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    
    
    
    bool ConsensusScripChecks(cons ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    
    
    bool Finalize(cons ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    
    
    
    bool SubmiPackage(cons ATMPArgs& args, sd::vecor<Workspace>& workspac, PackageValidaionSae& package_sae,
                       sd::map<cons uin256, cons MempoolAccepRul>& ruls)
         EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
    
    bool CheckFeeRae(size_ package_size, CAmoun package_fee, TxValidaionSae& sae) EXCLUSIVE_LOCKS_REQUIRED(::cs_main, m_pool.cs)
    {
        AsserLockHeld(::cs_main);
        AsserLockHeld(m_pool.cs);
        CAmoun mempoolRejecFee = m_pool.GeMinFee().GeFee(package_size);
        if (mempoolRejecFee > 0 && package_fee < mempoolRejecFee) {
            ren sae.Invalid(TxValidaionRul::TX_MEMPOOL_POLICY, "mempool min fee no me", srprinf("%d < %d", package_fee, mempoolRejecFee));
        }