There are some potential feefilter cleanups mentioned and motivated in comment https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-805808485 . If you address the locking one, please be careful and make sure that `round()` is only called under a lock. See https://github.com/bitcoin/bitcoin/pull/21509#issuecomment-807992199

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if (!pto->HasPermission(NetPermissionFlags::NoBan)) {
                        LogPrintf("Timeout downloading headers from peer=%d, disconnecting\n", pto->GetId());
                        pto->fDisconnect = true;
                        return true;
                    } else {
                        LogPrintf("Timeout downloading headers from noban peer=%d, not disconnecting\n", pto->GetId());
                        
                        
                        
                        
                        
                        state.fSyncStarted = false;
                        nSyncStarted--;
                        state.m_headers_sync_timeout = 0us;
                    }
                }
            } else {
                
                
                state.m_headers_sync_timeout = std::chrono::microseconds::max();
            }
        }
        
        
        ConsiderEviction(*pto, GetTime());