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?

{
            CSemaphoreGrant grant(*semOutbound);
            OpenNetworkConnection(CAddress(vserv[i % vserv.size()]), &grant);
            MilliSleep(500);
        }
        MilliSleep(120000); 
    }
}
bool OpenNetworkConnection(const CAddress& addrConnect, CSemaphoreGrant *grantOutbound, const char *pszDest, bool fOneShot)