Hi, a recent thread on dspace_tech [1] got me thinking about my previous experiences with caching, in other web development environments. In particular, a few years back, I did a lot of development using a PHP-based framework called ezPublish, and it had a caching scheme that could, on occasion, become aggressive. Their recommended safety net was to run a cron job to clear the cache every hour or so. Yeah, I know, kinda crazy (it's obviously a good way to hide a more serious bug). But part of me wants to code something similar (a command-line script for clearing the XMLUI/Cocoon cache), just to slap a bandaid on the problem and keep moving.
I mentioned this idea to Tim Donohue and Mark Diggory, to get their thoughts on whether I should chase after this impulse, and Mark suggested an alternative that would utilize the same idea (expiring the Cocoon cache) using existing functionality of Cocoon (my apologies to Mark for the cut and paste quoting to tell the story): On 10/13/11 11:53 AM, "Mark Diggory"<[email protected]> wrote: >We can actually utilize an expires parameter in the cocoon pipeline which >would force all caching to reload on a specified time period. TBH, I >would prefer this over the current situation, the real benefit of caching >is when there are multiple requests all piled on top of each other. So >yea Hardy, I agree with the premis of what your suggesting. On 10/13/11 2:55 PM, "Mark Diggory" <[email protected]> wrote: >Here is the detail for the 2.2 based approach which has a bit more >configurability. >http://cocoon.apache.org/2.2/core-modules/core/2.2/939_1_1.html >Note that we can get away with this by replacing one line in the default >sitemap :-) (look at other sitemaps to verify if its been overriden as >well). > ><map:pipe name="caching" > >src="org.apache.cocoon.components.pipeline.impl.ExpiresCachingProcessingPi >peline"> > <parameter name="cache-expires" value="180"/> <!-- Expires in seconds >--> ></map:pipe> Tim suggested that I send a note to dspace_developers to run this idea past a few of you. I think Mark has a good handle on what needs to change, and I think this should be a very simple change to implement. Hopefully in time for 1.8? I know it's very last-minute, but it's a simple change to the pipeline. I do intend to write a command line cache-clearing script at some point in the future, as an additional safety net. My experience with caching systems is that, even with expiry, they do tend to clog up. But, I believe that utilizing the expiration feature of the Cocoon caching pipeline is a good first step. Thoughts? [1] http://dspace.2283337.n4.nabble.com/item-counter-failed-td3896963.html -- HARDY POTTINGER <[email protected]> University of Missouri Library Systems http://lso.umsystem.edu/~pottingerhj/ https://MOspace.umsystem.edu/ "Debug only code. Comments lie." ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2d-oct _______________________________________________ Dspace-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dspace-devel
