doug@ross.UUCP (doug carmean) (03/17/89)
. .<21984@lll-winken.LLNL.GOV> brooks@maddog.llnl.gov (Eugene Brooks) Writes: >Even explicit cache flushing for the communication could be used, but >the cost of doing this is horrible context switching overhead for cache >sizes large enough to be useful. Your notion of including a context descriptor >in the cache line is useful for this, but one will still pay a cost when >you need to clear the cache of a specific descriptor upon process death. >At least, it is a better situation than having to clear the cache on every >context switch. . A cache that stores context numbers does not need to flush an entry upon the death of a given context. The cache will flush the entry when that particular context number is used again. A cache controller in this type of system will include a function to flush based on context number only. Flushing based purely on context will save the processor from having to flush the entire cache when a context is reused. -- -doug carmean -ROSS Technology, 7748 Hwy 290 West Suite 400, Austin, TX 78736 -ross!doug@cs.utexas.edu