Using ASMFS with NFS and fstab
One of the most interesting use cases for ASMFS seems to be the ability to list/read archivelogs on a remote (physical standby?) server as if they were normal local files. A quick mental image of how
My Oracle DBA & Sysadmin Blog
Notes on Oracle internals, SE2 workarounds, ASM, and performance tuning — written by an Oracle ACE who prefers the problems that aren't in the manual.
Latest articles
How direct-path inserts and one extra row per loop bloated 18 MB into 8 GB
I was investigating the code that looked something like this: truncate table t1; for i in 1..300 loop insert /*+ append */ into t1 select 1 from dual connect by level <= p_connect_by_level;
Migrating LOBs on Standard Edition with Materialized View Logs
LOBs can be stored as either BasicFiles or as SecureFiles. While both storage types are still supported in 19c, let me start by a quote from 12.1 documentation: SecureFiles is the default storage mec
The Hidden Cost of Login (Redo)
I was investigating an issue where there were a lot of user logins to Oracle database via listener due to misconfigured connection pool. This post explains why many logins could be a problem. Most would first think of the cost of process creation, me...
Reading Oracle ASM Files Directly Using x$kffxp
In a previous post, I explored implementing asmfs using dbms_diskgroup.read(). Since then, asmfs (my open source GitHub project) has gained a new capability: reading files stored in Oracle ASM by directly accessing block devices. Rather than needing ...
utl_recomp and Automatic Statistics Gathering
When recompiling invalid objects—often after patches, upgrades, or invalid dependency chains—you might call utl_recomp.recomp_serial. Since it's a serial procedure, one could reasonably expect it to avoid any parallel or background job interaction. B...
Legacy Clients on 19c
We've just migrated one of the last databases to 19c. The main area of concern for the client was that they were using rather old embedded devices, which had 11g client libraries and connect strings baked into their firmware. Here's the list of the m...
Oracle Flashback Database Automatic Deactivation
Today I learned that Oracle can disable the Flashback Database feature by itself automatically. Here's the reason - an excerpt from the alert log: ORA-38886: WARNING: Flashback database was disabled due to error when writing flashback database logs. ...
ASMFS & dbms_diskgroup.read
Here's what I've learned while trying to implement an ASMFS (which is an open-source GitHub project) and where my implementation fell short of my initial expectations. Initial Expectations I can access v$asm_file and v$asm_alias, which provide a comp...
