Oracle

Flame Graph for quick identification of Oracle bug

By Franck Pachot . Most of my performance stores start with a screenshot of Orachrome Lighty my preferred tool to have a graphical view of the database performance, in Standard and Enterprise Edition without any options:(…)

Oracle memory advisors: how relevant ?

By Franck Pachot . Do you look at memory advisors? I usually don’t but I still show them during the performance tuning workshop because there is no easy way to get an idea about memory sizing. This morning, while(…)

Convert a snapshot standby to a new database

By Franck Pachot . A snapshot standby database is a nice solution when you want a temporary copy of the primary where you can do whatever you want (test a bug fix for example) and then convert it back(…)

does impdb into a compressed table really compress data?

Today at a customer we discussed the following scenario: To refresh a test database a datapump export and import was implemented. To save space on the test system the idea came up to compress the data on the test system.

Variations on 1M insert (6): CPU Flame Graph

By Franck Pachot . If you followed the 1M rows insert variations, you have seen how something simple brought me into an investigation with the latest tools available to see where the time is spent. When the time is(…)

Variations on 1M rows insert(2): commit write

By Franck Pachot . In the previous blog post I measured the time it takes to insert 1 million rows. About 45 seconds when done row-by-row which goes down to 7 seconds when inserted in bulk. In both(…)

Variations on 1M rows insert (1): bulk insert

By Franck Pachot . This blog is the first one of a series about inserting 1 million rows. Do you have an idea about the time it takes? The idea came from another project, about NoSQL databases, but I’ll(…)

A migration pitfall with ALL COLUMN SIZE AUTO

By Franck Pachot . When you migrate, you should be prepared to face some execution plan changing. That’s not new. But here I’ll show you a case where you have several bad execution plans because lot of histograms are(…)

List listeners and services from the instance

By Franck Pachot . Want to know all your listeners – including scan listeners, and the services it listens for? It is possible from the instance, with the – undocumented – view V$LISTENER_NETWORK which is there since 11.2 Let’s(…)

Cloning a PDB from a standby database

By Franck Pachot . Great events like IOUG Collaborate is a good way to meet experts we know through blogs, twitter,etc. Yesterday evening, with nice music in the background, I was talking with Leighton Nelson about cloning PDB(…)