diff options
Diffstat (limited to 'guides/source/asset_pipeline.md')
| -rw-r--r-- | guides/source/asset_pipeline.md | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md index 84cda9222e..dd018c0da8 100644 --- a/guides/source/asset_pipeline.md +++ b/guides/source/asset_pipeline.md @@ -124,19 +124,22 @@ with a built-in helper. In the source the generated code looked like this: The query string strategy has several disadvantages: 1. **Not all caches will reliably cache content where the filename only differs by -query parameters** +query parameters** + [Steve Souders recommends](http://www.stevesouders.com/blog/2008/08/23/revving-filenames-dont-use-querystring/), "...avoiding a querystring for cacheable resources". He found that in this case 5-20% of requests will not be cached. Query strings in particular do not work at all with some CDNs for cache invalidation. -2. **The file name can change between nodes in multi-server environments.** +2. **The file name can change between nodes in multi-server environments.** + The default query string in Rails 2.x is based on the modification time of the files. When assets are deployed to a cluster, there is no guarantee that the timestamps will be the same, resulting in different values being used depending on which server handles the request. -3. **Too much cache invalidation** +3. **Too much cache invalidation** + When static assets are deployed with each new release of code, the mtime (time of last modification) of _all_ these files changes, forcing all remote clients to fetch them again, even when the content of those assets has not changed. |