The method you describe seems overly complex. Why not run 3 different
exports simultaneously and then 3 different imports simultaneously? I once
wrote a something like that using 6 streams for the export and 6 for the
import, and it worked very well. It took some thought to break everything
up logically without dependence issues, but once done (it was a process we
had to repeat frequently), I just used a shell script to nohup the export
processes, and it worked very smoothly.
On Tue, Dec 29, 2015 at 3:45 PM, Storey, Robert (DCSO) <
RStorey@xxxxxxxxxxxxxxxxxx> wrote:
In this case it would be part of a LUN in a SAN. But, the new hardware I
am going to migrate it to (when it gets here) will have 12 disks. I will
create 6 mirror pairs, and then stripe across the pairs. 2 separate disks
will hold my redo. So, data and indexes will go onto the raid10 where
logical volumes will be created just for ease of structure (windows
environ).
And my bottleneck has been the table in schema c that has the XMLTYPE as a
column. That one table seems to take 12 hours, regardless of how I
approach it. I’m still working on speeding it up, or eliminating it from
the import.
*From:* Raza Siddiqui [mailto:raza.siddiqui@xxxxxxxxxx]
*Sent:* Tuesday, December 29, 2015 3:42 PM
*To:* Storey, Robert (DCSO)
*Cc:* Oracle L
*Subject:* Re: Multiple imports simultaneous?
Overall # of rows is not huge (in today's terms), or schemas or
objects...what is more important is mapping of your tablespaces to their
corresponding files to physical disks - that would be your possible
bottleneck.
Raza
On Dec 29, 2015, at 13:28, "Storey, Robert (DCSO)" <
RStorey@xxxxxxxxxxxxxxxxxx> wrote:
Just curious about import.
I’m importing an older 9i system into an 11g system. I am precreating the
tablespaces, etc.
Ultimately, the import only cares about 3 schemas. One that only has my
PL/SQL and the other two have the data. So, Schema A, B, C. Schema B has
about 360 tables and about 190 million rows total. Schema D has about 45
tables, but and about 35 million rows of which 27 are in one table that has
an XMLTYPE column. Importing just the one table in Schema B takes about 12
hours. I’m working on methods to trim that time.
But, is it possible to do multiple imports at once if using different
inbound schemas.
1) Export the database to create my dump file.
2) ON the target server, make 3 copies of the import file.
a. Do an import of Schema A, rows=n, indexes=n, constraints=n
b. Do an import of Schema B, rows=n, indexes=n, constraints=n
c. Do an import of Schema C, rows=n, indexes=n, constraints=n
3) Do an import for each schema where rows =n, and indexes and
constraints = y.
Theoretically, this should not interfere with each other. I can set the
database to no-archive and increase redo logs so that the waits should be
reduced.
Thoughts?
