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I'm a little confused here. How does the cache keep track of which operating system thread is running and making a transaction? In other words, how does the cache know who's read/write bits are being set? These caches are per core/per processor, so I'm not sure how you would be able to save all of the read/write bits per cache line every context switch.


@fkc9001: It doesn't look like you need to know who actually did the writes and reads. If there is a conflict detected, then all read/write bits on all cached data is cleared, and I assume that the thread doing the conflicting transactions are dealt with in software.

This might change from policy to policy. I'm not sure how lazy versioning and eager versioning would differ in this example. Since all writes and reads are logged as bits, the undoing of a log would be to clear these bits. Maybe its a difference in cache coherency?