During some lock debugging on a dual-core Linux system I noticed that threads are blocked acquiring `cs_vNodes` and `cs_main` for long periods when the system is under moderate load from unrelated processes -- the unlucky lock acquirer is waiting for single-digit seconds once every 10 minutes or so (not coinciding with new blocks) up to around a 30 second wait every few hours. It looks like `ThreadMessageHandler` is taking locks and then due to being set to `THREAD_PRIORITY_BELOW_NORMAL`, it's being descheduled (even in trivial lock-holding regions like `GetHeight`) and holding up for arbitrarily long periods other threads that use these core locks.

So I'm wondering, what are the benefits of running the message handler at low priority?

continue;
            if (FD_ISSET(pnode->hSocket, &fdsetSend))
            {
                TRY_LOCK(pnode->cs_vSend, lockSend);
                if (lockSend)
                    SocketSendData(pnode);
            }
            
            
            
            int64_t nTime = GetTime();
            if (nTime - pnode->nTimeConnected > 60)
            {
                if (pnode->nLastRecv == 0 || pnode->nLastSend == 0)
                {
                    LogPrint("net", "socket no message in first 60 seconds, %d %d from %d\n", pnode->nLastRecv != 0, pnode->nLastSend != 0, pnode->id);
                    pnode->fDisconnect = true;
                }
                else if (nTime - pnode->nLastSend > TIMEOUT_INTERVAL)
                {
                    LogPrintf("socket sending timeout: %is\n", nTime - pnode->nLastSend);
                    pnode->fDisconnect = true;
                }
                else if (nTime - pnode->nLastRecv > (pnode->nVersion > BIP0031_VERSION ? TIMEOUT_INTERVAL : 90*60))
                {
                    LogPrintf("socket receive timeout: %is\n", nTime - pnode->nLastRecv);
                    pnode->fDisconnect = true;
                }
                else if (pnode->nPingNonceSent && pnode->nPingUsecStart + TIMEOUT_INTERVAL * 1000000 < GetTimeMicros())
                {