3 ms·
Their assumption of 64 bytes cacheline is unrealistic. Most CPU architecture use 64 bit cacheline (1/8 of 64 bytes), for good reasons. 512 bit cacheline is insa
by cramcram 8y ago
Their assumption of 64 bytes cacheline is unrealistic. Most CPU architecture use 64 bit cacheline (1/8 of 64 bytes), for good reasons. 512 bit cacheline is insane.
Also, good compression requires large corpus / large model - thus page-based compression is much more useful in real life. For example Google's ChromeOS uses zram by default since 2013 [1].
[1] https://en.wikipedia.org/wiki/Zram https://en.wikipedia.org/wiki/Zram
- nightcracker 8y agoCorrect me if I'm wrong, but doesn't virtually every modern Intel and AMD chip use a 64-byte cache line? If you were to use a 64-bit cache line you're just retrieving one word at a time.
- TickleSteve 8y agozram is simply a compressing ram disk driver, nothing remotely to do with what we're talking about here apart from the basic principles. The cache line size is indeed 64 bytes, not bits as caching less than the bus-width wouldn't really make much sense.
- blattimwind 8y ago> Most CPU architecture use 64 bit cacheline (1/8 of 64 bytes), for good reasons. 512 bit cacheline is insane. No. 64 and 128 (to a lesser extent) bytes are pretty much the only extant cache line sizes these days. 64 bit cache lines would be insane.