subversion intermittently hangs (stalls) on commit

Thanks to GeraldSchneider's detailed description of a similar issue I was able to identify that the problem had to do with an LDAP authentication setting known as LDAPConnectionPoolTTL. The challenge was to find out how to adjust that setting within the CollabNet administration portal. It is not on the Authentication page. Rather, you must navigate to "Server Settings", then click the "Advanced Settings" link, and at the bottom of that page there are these two fields:

Connection Pool TTL (default: -1 -- attempt to reuse connections indefinitely)

and,

Timeout (default: 60 seconds; this corresponds to the LDAP response time)

I am not exactly sure what the optimal settings for those fields are. I have found numerous suggestions on various forums:

• Gerald's post suggested setting the Pool TTL to 0, disabling the reuse of existing connections, but it is unclear to me what performance hit this might incur.
• One forum suggested 60 seconds on Pool TTL
• Two other forums suggested 900 on the Pool and 10 for the Timeout (along with some additional changes to the httpd.conf file).
• Atlassian recommends 30 seconds on the Pool TTL, and IBM recommends 10.

Personally, I have decided to experiment with a setting of 899 for the Pool TTL and reducing the LDAP response timeout to 10.