-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jan and Matthias,
Reich, Matthias wrote: | I think it is better to start one background worker thread and pass | the log requests to that thread with the help of a queue. Definitely. Otherwise, you could have threads piling up on one another if every request spawns another thread (and waits a bit to do the lookup). | You can | also consider to let the worker cache the DNS lookup results. | (Usually you will see requests from the same clients lots of times.) Another good idea. Another idea would be to do the lookups later, as part of a post-log-processing process. For instance, our production site uses Apache to log requests without reverse DNS lookup. When we run webalizer to generate graphs and stuff for the logs, we have webalizer do the reverse DNS lookup at that time. That way, the app server (or web server in our case), never has to do the lookup at all. This might be an option for you. Finally, the servlet specification allows containers to constrain webapps in certain ways, including the creation of threads (so that webapps are less likely to cause instability): ~From section 1.3 (spec v2.5): "A servlet container may place security restrictions on the environment in which a servlet executes. In a Java Platform, Standard Edition (J2SE, v.1.3 or above) or Java Platform, Enterprise Edition (Java EE, v.1.3 or above) environment, these restrictions should be placed using the permission architecture defined by the Java platform. For example, high-end application servers may limit the creation of a Thread object to insure that other components of the container are not negatively impacted." Also note that you should capture the IP address from the request before handing anything off to another thread (or to a queue that will be processed by another thread). You certainly do not want to store the request object itself anywhere: it breaks the spec (see below) and it WILL break your application. ~From section 2.3.4: "References to the request and response objects should not be given to objects executing in other threads as the resulting behavior may be nondeterministic." (And they're not kidding!) Good luck, - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAke0dxgACgkQ9CaO5/Lv0PCr+QCgp1uxyDZonjPWV3rnzmB0Nypl hfEAn088ftX6aes/rMh+re33y8/OLgSS =GJnF -----END PGP SIGNATURE----- --------------------------------------------------------------------- To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
