When you say "internal search engine" do you mean Lucene? I presume by "external" you mean something like Google? At any rate, I think the problem is either in Lucene or in that "edu.oswego" library you are using to schedule index writes. I think what's happening is that at sustained high rate of posts the threads wanting to write to Lucene index are piling up and causing the problem. Sadly, I don't think concurrency level needed to expose this bug is very high at all. I've been able to reproduce this with as few as 5 concurrent users making posts.

My fear is that this is something fundamental to the way Lucene manages its indexes and I suspect it's not an easy fix. I mean this is the kind of problem that database vendors have to deal with pretty sophisticated solutions. How receptive would you (and the community) be to a proposal for changing real-time writes to some sort of batched mode where a process is run periodically which is responsible for indexing un-indexed entries?

Max


On Jun 28, 2005, at 10:52 PM, Allen Gilliland wrote:

I'm not sure if we've ever isolated things down to exactly that problem, but for blogs.sun.com we've definitely had a number of problems with the built in search engine. I believe a number of the problems have been fixed, so maybe if you aren't using the latest cvs already then you can run your tests against the 1.2 release coming up and see what happens. Unfortunately we won't be the best help with search problems because we use an external search engine and so we currently have Roller's built in search disabled.

-- Allen


Rudman Max wrote:


We've been testing Roller with some pretty high load (about 500 concurrent users) running search (which reads from the index) and posts (which writes to the index) transactions. After a while, we'd run out of file handles which froze Tomcat because it could no longer open sockets to accept incoming connections. Our sysadmin told me there were a bunch of orphaned file descriptors on files in /roller- index directory. I am not sure if that's the reason for Tomcat process running out of files but it seems likely. Has anybody ever experienced this problem with Roller search index?

Max



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