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Showing posts from June, 2010

Performance

Ubuntu 9.10 ext4 copy disk->disk ~22-29MB/sec ~25MB/sec avg ~1.4GB/min ~10min to copy 14GB

Java DNS cache

Replace Java DNS with dnsjava Prior to Java 6 DNS resolutions were cached forever. Defaults: Java 6 DNS positive responses are cached for 30 seconds and negative responses for 10 seconds -Dsun.net.inetaddr.ttl=3600 By default, when a security manager is installed, in order to protect against DNS spoofing attacks, the result of positive host name resolutions are cached forever. When a security manager is not installed, the default behavior is to cache entries for a finite (implementation dependent) period of time. The result of unsuccessful host name resolution is cached for a very short period of time (10 seconds) to improve performance.

HTML and CSS

div and span

Adobe Reader Install - Ubuntu

HOWTO

JBoss

Scan rate to detect changes, i.e., jsp <JBOSS-INSTALL_DIR>\server\<server config>\conf\jboss-service.xml <!-- Frequency in milliseconds to rescan the URLs for changes --> <attribute name="ScanPeriod">5000

JNDI testing

OOC-JNDI

Trillion node network

Trillions video trillion node network scalability - no central authorities (registration, namespaces, ontologies) no device individual attention tracktability size can't increase complexity comprehensiveness bit, byte, name/value Internet of Things