Sharing, Contributing… and Caching

“After several weeks of development work, we had sown JBoss
Cache into our development version of the Guardian website, and
found that it performed well under quick 1-hour stress tests. Then
we performed a long running soak test, starting on Friday
afternoon. We went home, came back on Monday morning, and found a
graph like this:

“Our cache fills up- and then mysteriously starts to
empty…

“Oh dear. Verrrrrry Bad. The cache was, for some reason, getting
smaller and smaller over time. In our case, It Really Shouldn’t Do
That. The cache – the cache we so desperately depend on to take
load off the database – should stay 100% full all the time. If our
cache starts to evaporate without explanation, well, that’s just
not going to do anyone any good.

“We investigated. This part should be fun, but there are a lot
of unknowns. Are we doing something wrong? Is there something wrong
with JBoss Cache? If so, why doesn’t everyone else see it? Yet in
the face of these unknowns, we can do this. JBoss Cache is Open
Source – we can read the code.”

Complete Story