Only generate diffs once during a reasonable period of time, and do it in advance, when there is low load, if possible.
ConfigEntities are not revisioned, so separate is #1821548: Add a "diff" of some kind to the CMI UI.
I recently started using the diff module and find that it's extremely slow on some pages. For example, on my computer a "node/383/revisions/view/385/998" page is taking more than 40 seconds CPU time to generate. I used XDebug and kcachegrind and found that 90% of the time is spent in the diff algorithm.
| Comment | File | Size | Author |
|---|---|---|---|
| diff_cache.patch | 1.1 KB | yang_yi_cn |
Comments
Comment #1
yang_yi_cn commentedBTW, the slow page I mentioned has HTML content for about 1000 lines.
Comment #2
realityloop commentedAdded to both 6 and 7 branches
Comment #3
greenreaperThis is a nice idea, but it assumes that revisions are immutable, which is not the case. When you edit an existing revision's text, the diff cache is not invalidated, and so subsequent diffs return stale results.
Perhaps there is a way to hook "revision X changing" and reset the diff cache? Though I'm not sure how you'd detect which revisions had cache entries . . . a more sophisticated cache system might be required.
It might also be a good idea to use the CACHE_TEMPORARY parameter for $expire, since these diffs could be of significant size and needn't hang around forever.
Comment #4
realityloop commentedOK is seems this isn't really a good addition, I never thought it would cause much load anyway, I am going to remove it unless someone cares to update the patch taking into account GreenReapers suggestions
Comment #5
akanik commentedI just wanted to make sure my issue is the same as this one....
When revising an article (any node), applied changes show when you go to admin > content and open the node that way, or when you use "list all revisions" (on a node revision page) > "compare" or when you access the node from the "Revisions Pending" block or yourdomain.com/content-summary.
Changes do not show when you attempt to access the node from "revisions" > "list all revisions" > then by clicking on the revision save date.
Please let me know if that was unclear or it this is another issue (either with the module of my competency).
Thanks so much,
allie
Comment #6
mitchell commentedBumping to 7.x-3.x
See also #1371916: Restructure around the Entity / Field system.
Comment #7
mitchell commented#1371916-2: Restructure around the Entity / Field system and a number of other issues in the queue are duplicates, because many of these features require read-accessible-caches, and this issues is about generating caches. Entity Cache would be an ideal backend to use for diff caching, because of the existing Entity API integration, which could also be used for generating views and tokens.
Entity Cache Management can be done with Cachetags and Entity Cache integration, see #1322236: Integration with contrib (entitycache, diff, nodequeue and panels). Cachetags is a robust alternative to using Rules. Another caching strategy to consider with waiting until the first view of a revision to generate its diff, would be to generate valid caches (non-time sensitive) when a revision is created, and also, regenerate caches when revisions are changed. Something along those lines.
Comment #8
mitchell commentedComment #8.0
mitchell commentedx
Comment #8.1
mitchell commentedx
Comment #9
mgiffordComment #23
smustgrave commentedThank you for sharing your idea for improving Drupal.
We are working to decide if this proposal meets the Criteria for evaluating proposed changes. There hasn't been any discussion here for over 8 years which suggests that this has either been implemented or there is no community support. Your thoughts on this will allow a decision to be made.
Since we need more information to move forward with this issue, the status is now Postponed (maintainer needs more info). If we don't receive additional information to help with the issue, it may be closed after three months.
Thanks!
Comment #24
smustgrave commentedSince there's been no follow up in 3+ months going to close this one out. If still valid please re-open
Thanks!