Re: Slow Oracle export

In a previous article, lionell_at_solomon.technet.sg (Lionel Lee Yuin) says:

>Hi,
>
>We are running Oracle 7.0.13 on Solaris 2.2. Recently, we discovered that
>our export was taking an extremely loooooonnnnng time to complete (8-9 hrs).
>
>A test database of 4M exported file size took 1 min to complete but the
>production database of 157M exported file size took 8 to 9 hrs to complete.
>In short, though the difference in exported file size is 40 times, the
>timing difference is 480 times.

1. I would suggest you make sure there are no "ANALYZE" statistics on any of the SYS or SYSTEM tables. Back when I had 7.0.11 I ran Analyze on the data dictionary just for fun and export ran at a blinding standstill. (The 7.0.12 release came out with a big warning against this in it's README.doc file).
2. Make sure export is connecting with a dedicated server process. Running export, import or SQL*Loader through a dispatcher really slows things down.
3. If it's any consolation...(or if the cd-rom is in the mail)...I noticed a substantial (4 times) improvement in export performance when I upgraded to 7.0.15.4 last week. My database has about 400M of data scattered about in it these days, and the full database export runs (across the network and onto a tape, with INCTYPE=FULL) in about 35 min. (I'm running SunOS 4.1.3 on a 670MPx2). With 7.0.12 the same export took two hours.

   Good Luck

-- 
   - Doug Harris
     Database Administrator,
     System Development Division,
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