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?

{
        pnode->PushInventory(inv);
    }
}
void CNode::RecordBytesRecv(uint64_t bytes)
{
    LOCK(cs_totalBytesRecv);
    nTotalBytesRecv += bytes;
}
void CNode::RecordBytesSent(uint64_t bytes)
{
    LOCK(cs_totalBytesSent);
    nTotalBytesSent += bytes;
    uint64_t now = GetTime();
    if (nMaxOutboundCycleStartTime + nMaxOutboundTimeframe < now)
    {
        
        nMaxOutboundCycleStartTime = now;
        nMaxOutboundTotalBytesSentInCycle = 0;
    }
    
    nMaxOutboundTotalBytesSentInCycle += bytes;
}
void CNode::SetMaxOutboundTarget(uint64_t limit)