..By crash I mean spinning for a few minutes and then returning a 504 gateway timeout.
This usually seems to happen when an RSS was valid when originally added but has now become invalid . For example: http://bja.oxfordjournals.org/rss/recent.xml
At some point in time the above must have been a valid uri is why Moodle would have allowed the user to add it .
Steps to re-create:

1) Add a broken RSS directly through the database under block_rss_client table.
2) Assign the RSS to an RSS block in a course
3) Display the course

Because Moodle cant get to the RSS anymore it fails to the load the course page where the RSS was added. This was not the case in earlier Moodle version where a broken rss feed would generate a simple pie error but would still continue to load the page

My moodle instance's block_rss_client_timeout is set to 1 minute but this does not seem to be working. Also, what is the use of skiptime besides delaying the check on rss feeds via the cron ? Does it also take into account to not display the rss feed on a course page after a certain skiptime value ?

Thanks

Hittesh Ahuja