Forum .LRN Q&A: 15MB read from disk!
It seems to happen whenever the #dotlrn-fs.Lecture-Notes# portlet is used in a class, or #fs-portlet.pretty_name# - even if there are no added files. Checking what is going on in postgres, it seems that there is a particularly huge select statement, which, even if run of the pgsql command line, takes an age to return a (very small) table of results:
select fs_objects.object_id, fs_objects.name, fs_objects.live_revision, fs_objects.type, to_char(fs_objects.last_modified, 'YYYY-MM-DD HH24:MI:SS') as last_modified,fs_objects.content_size, fs_objects.url, fs_objects.sort_key, fs_objects.file_upload_name, etc etc etc etc etc etc etc.
Is this a statement that that has been optimised in some way for oracle?
I'll look into it.
Note, though, that due to our effort being pointed towards an OpenACS 4.6.2+dotLRN 1.0 release, any such fix will appear in the dotLRN 1.0 branch, not HEAD. We'll be merging the two in a couple of weeks but until then you're best off with those two branches.