TheBonsai's Blog

Auf der Suche nach einem Batch Scheduler für Linux habe ich mir 2 Stück genauer angesehen und bin zu einem verblüffenden Ergebnis gekommen, das eindeutig besagt dass geile GUIs definitiv nicht alles sind Dies ist keine volle Review, sondern nur eine kleine Aufzählung von Pro/Contra Punkten

• GNU Batch (ehem. XI Batch)
• SOS Scheduler

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Recently I hacked a on-demand-export for a user. After his (small) data loading, an export is triggered to have his data in a backupable and tranmsportable file. The total amount of all tables was about 7MB only.

The export routines were done with datapump export. I watched a manual run and…

• datapump started and connected to a database server process: 3 seconds
• datapump estimated and analyzed the data to export: 36 minutes
• datapump exported the relevant tables: 4 seconds

Do you see what I see? Yes? Right, datapump played with itself. Over 36 minutes of runtime, where 99% of the time not one bit of data was moved. Reproducable 100%. A datapump TRACE=480300 generated trace set revealed a huge delay in the worker process when calling DBMS_METADATA.FETCH_XML_CLOB (exactly my 36 minutes).

The solution was a patch for bug

• 7710931: DATAPUMP EXPORT IS EXTREMELY SLOW WHEN EXTRACTING SCHEMA

Now datapump does what it’s designed for: Pumping data without playing with itself!

Da wird man in einer technischen Diskussion so nebenbei zum alten Sack abgestempelt…

<greycat>   # mkdir foo; cd foo; rmdir ../foo; mkdir ../foo; touch bar
<evalbot>   greycat: touch: cannot touch `bar': No such file or directory
<greycat>   That's what I had been attempting to demonstrate with the previous evalbot test...
<TheBonsai> but this behaviour is no surprise
<greycat>   It's no surprise if you're a unix veteran.
<TheBonsai> er... greg i'm 30, wrong aage
<greycat>   Been using Unix for more than 5 years?
<TheBonsai> yes, definitely
<greycat>   Veteran.
<TheBonsai> *shocked*

(Quelle: IRC Channel #bash auf dem Freenode IRC Netzwerk, irrelevanter Text entfernt)