RMAN question

[roukie_dba]

Dear members
I have an rman script with the following command:

{.....
setlimit channel chan1 kbytes 209150 readrate 28;

}

How do they arrive at the number 209150???

Thanks in advance!

[Sureshy]

The readrate value is the maximum number of buffers per second. The buffer size is the result of multiplying the init.ora settings DB_FILE_DIRECT_IO_COUNT and DB_BLOCK_SIZE. Setting the readrate value inevitably involves a level of trial and error and is application- and hardware-specific

[julian]

The buffer size is the result of multiplying the init.ora settings DB_FILE_DIRECT_IO_COUNT and DB_BLOCK_SIZE.

OS BLOCK SIZE not DB_BLOCK SIZE.
I use the deefault DB_FILE_DIRECT_IO_COUNT of 64 having 512 OS block size.

This is from my trace file:

*** SESSION ID:(2.1) 2001-09-12 19:57:12.758
kjxggin: receive buffer size = 32768
kgxggin: SKGXN ver (2 0 dlm reference implmentation of skgxn)
kgxggcs: Setting state to 0 0.

Now, 32768 = 64*512.

[Sureshy]

If you read the following article you will notice that it is DB_FILE_DIRECT_IO_COUNT and DB_BLOCK_SIZE.

http://www.oracle.com/oramag/oracle/...ml?o20rec.html

[julian]

Good article, thanks for the link, I also knew that it is DB_BLOCK_SIZE but when I started calculating I found out that it is OS BLOCK SIZE. You know if it looks like a duck, if it quacks like a duck, then it is a duck :-)