This is a bit of a rant, I know but... One thing I would like to see Sun do, from the point of view of my previous role at work, would be to devote more effort to improving the stability and performance of the Hotspot VM on all platforms.
>From what I can see are a number of defects in the Hotspot VM that seriously affect the capapacity of many server products to achieve high uptimes and high throughputs. Is this experience borne out by anyone else here? Could we see some clarification of the garbage collection and optimisation mechanisms? It seems to me that there are a very large number of poorly documented options for garbage collection and optimisations which are neither specification features nor implementation features, but are in wide use by many people who are struggling to maintain high levels of service in the real world in the face of defects and failure of the JVM to behave as documented. One example is the permanent generation size, Sun tell us that allocations in the permanent generation will continue up to the maximum size of the permanent space, at which point further allocations will be from the tenured heap space. Seems sensible so far. However it appears that requests for permanent allocation trigger a full garbage collection when they cannot be satisfied in the permanent generation, this leads to the JVM thrashing and effectively defeats the notion that tenured space could be used as an overflow. The fact that this was not documented is almost as serious because it removes some of the imperative which might otherwise encourage us to profile not only hepa usage but also permanent generation requirements. d. *************************************************************************** The information in this e-mail is confidential and for use by the addressee(s) only. If you are not the intended recipient (or responsible for delivery of the message to the intended recipient) please notify us immediately on 0141 306 2050 and delete the message from your computer. You may not copy or forward it or use or disclose its contents to any other person. As Internet communications are capable of data corruption Student Loans Company Limited does not accept any responsibility for changes made to this message after it was sent. For this reason it may be inappropriate to rely on advice or opinions contained in an e-mail without obtaining written confirmation of it. Neither Student Loans Company Limited or the sender accepts any liability or responsibility for viruses as it is your responsibility to scan attachments (if any). Opinions and views expressed in this e-mail are those of the sender and may not reflect the opinions and views of The Student Loans Company Limited. This footnote also confirms that this email message has been swept for the presence of computer viruses. ************************************************************************** --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
