Estimating DB Time With ASH: Logon Storm Pitfall
Logon storms may substantionally contribute to DB time which isn’t captured in active session history. Continue Reading
Author: Nenad Noveljic
Do You Know Your Object-Relational Mapper’s Overhead?
A call to ORM API can comprise of much more than a database call. Its overhead can be measured. Continue Reading
Writing a BLOB to a File – Comparison Between PL/SQL and Java
Undocumented UTL_FILE internals – possible performance degradation with BLOBs Continue Reading
Expected Payoff of the Gaussian Distribution Tail Part 2
Ratio of the expected payoff above some value and the impact of that value multiplied by the probability of exceeding it (in thin tailed distributions) Continue Reading
Expected Payoff of the Gaussian Distribution Tail
Expected payoff of the Gaussian distribution tail for a linear payoff function Continue Reading
Troubleshooting java.lang.OutOfMemoryError in the Oracle Database
Internal processing of critical Java errors in the Oracle database Continue Reading
Slow DMLs With Larger Blocks
Why DML performance drops with large block sizes and checksums turned on. Continue Reading
Converting High-Resolution Time to a Human Readable Format
How to convert a time stamp in SQL trace to wall clock time Continue Reading
Warning: log write elapsed time
Oracle database internals – (redo) “log write elapsed time” instrumentation Continue Reading
Automating Multi-Tenant Container Database Creation
There are two ways of creating multi-tenant container databases (CDB): Database Configuration Assistant and scripts. With the latter you have to run the script catcdb.sql for building data dictionary. This script calls a cascade of other Perl and sqlplus scripts,… Continue Reading