4 ms·
The usual phrase is "scan resistance", which is especially important for databases. A pure LRU policy does poorly on scans; LFU does better but performs worse t
by senderista 3y ago
The usual phrase is "scan resistance", which is especially important for databases. A pure LRU policy does poorly on scans; LFU does better but performs worse than LRU on other workloads. The original ARC paper[0] has a good discussion of the tradeoffs.
[0] https://www.usenix.org/legacy/events/fast03/tech/full_papers/megiddo/megiddo.pdf https://www.usenix.org/legacy/events/fast03/tech/full_papers...
- falsandtru 3y agoScan resistance and loop resistance are completely different. They are also distinguished in the papers. Note that ARC has scan resistance but no loop resistance.
- medler 3y agoNone of the papers linked above or linked in the GitHub repo mention “loop resistance.”
- senderista 3y agoNot completely different; they're both sequential access patterns and equivalent whenever the loop size exceeds cache size.
- falsandtru 3y agoNot equivalent completely. Scan is a one-time access, so it never hits in scanning. Loop is multi-time accesses, so it can get many hits in looping if it has loop resistance. No hits on scan resistance in looping. Over.
- falsandtru 3y agoI am disgusted by people who are repulsed by even the correction of a complete error. They must have bad grades in college. From now on, we have no choice but to leave it alone even if a false rumor is spread.