Cache Notes: Difference between revisions

Revision as of 18:37, 13 July 2010

Here are some things we can investigate to gain more information about the current state of the cache:

Determine what the cache's average hit rate is.
See how performance varies by increasing the cache size.
Look into whether YouTube files are blowing out the cache.
Run a Test Pilot or a smaller experiment to gather user cache data
- In order to gather info on the previous bullet points

Here are some ideas for improving the cache that need to be investigated:

Consider other eviction options
- Prioritize by file type, giving css and js higher priority
- Evict based on frecency, not just recency (frequency + recency)
- Use Adaptive Replacement Cache algorithm: http://en.wikipedia.org/wiki/Adaptive_replacement_cache
- We could consider letting servers specify "cache-priority" with resources. This leads to other issues, like fairness.

Keep dimensions of evicted img files, so layout can still render before the image data arrives across the network
Compress cache entries?
- This could save space and improve I/O time

Here are some links with other documentation on the cache.

Here is a list of bugs filed on the cache. Many are resolved.

@@ Line 15: / Line 15: @@
 **Evict based on frecency, not just recency (frequency + recency)
 **Use Adaptive Replacement Cache algorithm: http://en.wikipedia.org/wiki/Adaptive_replacement_cache
+**We could consider letting servers specify "cache-priority" with resources. This leads to other issues, like fairness.
 *Keep dimensions of evicted img files, so layout can still render before the image data arrives across the network