Posted Aug 31, 2009 16:02 UTC (Mon) by dlang (✭ supporter ✭, #313)
In reply to: HWPOISON by jzbiciak
Parent article: HWPOISON
if background scrubbing triggers a read error with HWPOISON, that defeats the purpose of doing the HWPoISON in the first place, you may as well just die when you first detect the error.
the key of HWPOISON is that not all memory locations contain irreplaceable data. in some cases the memory may not be allocated (so when the program goes to use it, whatever contents are there are going to be erased anyway), on other cases the data exists elsewhere (clean disk buffer pages that can be re-read from disk, etc)
so instead of erroring out when memory corruption is detected, it only throws an error if something tries to make use of the corrupt data, and even then it throws an error that the OS can catch and deal with (since only the OS knows if the data can be replaced by something read from somewhere else)