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?

#else
#ifdef _MSC_VER
#pragma warning(disable:4786)
#pragma warning(disable:4804)
#pragma warning(disable:4805)
#pragma warning(disable:4717)
#endif
#ifdef _WIN32_WINNT
#undef _WIN32_WINNT
#endif
#define _WIN32_WINNT 0x0501
#ifdef _WIN32_IE
#undef _WIN32_IE
#endif
#define _WIN32_IE 0x0501
#define WIN32_LEAN_AND_MEAN 1
#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <io.h> 
#include <shlobj.h>
#endif
#ifdef HAVE_SYS_PRCTL_H
#include <sys/prctl.h>
#endif
#include <boost/algorithm/string/case_conv.hpp> 
#include <boost/algorithm/string/join.hpp>
#include <boost/algorithm/string/predicate.hpp> 
#include <boost/filesystem.hpp>
#include <boost/filesystem/fstream.hpp>