ORION - ORacle I/O Numbers - I/O Bench-marking Tool in Oracle

ORION - ORacle I/O Numbers :  An I/O Bench-marking Tool in Oracle


Generally, you do the workload testing of your production database system or the new hardware arrived in your data center when your Oracle RDBMS server already running with actual application data but you can simulate the similar I/O testing with Oracle provided Tool called "Orion", an I/O bench-marking Tool. It helps you predict the performance of I/O Bench-marking for new hardware system for Oracle database.

The ORION tool has been available for some time now and honestly I was not aware of it so far. While exploring the advanced performance tuning of Oracle RDBMS, I came to know about this nice pre-bundled script to evaluate the I/O performance of your Oracle database on new hardware where you are going to deploy or migrate your database.

Initially this tool was available to download from Oracle OTN but since Oracle 11.2 onward, it is bundled inside Orale RDBMS database software package itself. So you can invoke from $ORACLE_HOME/bin directory to work with it.

ORION works best during the evaluation phase of new platform without application-data on your logical unit numbers(LUNs). It is specifically designed to simulate the I/O workload on your new hardware system for Oracle database. This package uses asynchronous I/O and large pages for read and writes to concurrently submit I/O requests to operating system. Asynchronous I/O uses "libaio" on Linux platform. You can quite easily see that the ORION slave processes use "io_submit" and "io_getevents" by tracing strace on this.


Here, let's go ahead and fake some LUNs to perform evaluation of I/O on it.

-bash-4.1$ dd if=/dev/zero of=lun01.file bs=1G count=1
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 24.0865 s, 44.6 MB/s


-bash-4.1$ dd if=/dev/zero of=lun02.file bs=1G count=1
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 12.9167 s, 83.1 MB/s


-bash-4.1$ dd if=/dev/zero of=lun03.file bs=1G count=1
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 1.00802 s, 1.1 GB/s


-bash-4.1$ dd if=/dev/zero of=lun04.file bs=1G count=1
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 1.01502 s, 1.1 GB/s

You can see LUNs are faked inside /u01 mount by listing the directory.

bash-4.1$ pwd
/u01
-bash-4.1$ ls -ltr *.file
-rw-r--r--. 1 oracle oinstall 1073741824 Oct 17 06:53 lun01.file
-rw-r--r--. 1 oracle oinstall 1073741824 Oct 17 06:53 lun02.file
-rw-r--r--. 1 oracle oinstall 1073741824 Oct 17 06:54 lun03.file
-rw-r--r--. 1 oracle oinstall 1073741824 Oct 17 06:54 lun04.file




Once the LUNs are created, make a group file with list of LUNs we created earlier with its obsolute file path. I created a group file /u01/orion.lun as below.

-bash-4.1$ cat /u01/orion.lun 
/u01/lun01.file
/u01/lun02.file
/u01/lun03.file
/u01/lun04.file

Finally, invoke orion executable from $ORACLE_HOME/bin location as below. As soon as you start the command to evaluate the I/O testing, this tool will tell you the approximate time it will take to complete.

-bash-4.1$ $ORACLE_HOME/bin/orion -run oltp -testname /u01/orion -hugenotneeded

Output should be like below.

Below I have generated a graph based on above out to relate Latency and and corresponding # No. of I/Os(Read) per second. You can realise that lower the latency the higher #No. of I/O(Reads)

As part of the I/O performance evaluation, orion tool creates multiple CSV files, text files with detailed metrics you should look at for evaluating IOPS, MBPS operations.

-rw-r--r--. 1 oracle oinstall   355 Oct 17 07:00 orion_20171017_0700_summary.txt
-rw-r--r--. 1 oracle oinstall     0 Oct 17 07:00 orion_20171017_0700_mbps.csv
-rw-r--r--. 1 oracle oinstall     0 Oct 17 07:00 orion_20171017_0700_lat.csv
-rw-r--r--. 1 oracle oinstall     0 Oct 17 07:00 orion_20171017_0700_iops.csv
-rw-r--r--. 1 oracle oinstall     0 Oct 17 07:00 orion_20171017_0700_hist.txt
-rw-r--r--. 1 oracle oinstall   515 Oct 17 07:00 orion_20171017_0700_trace.txt
-rw-r--r--. 1 oracle oinstall 56161 Oct 17 07:22 orion_20171017_0702_trace.txt
-rw-r--r--. 1 oracle oinstall   570 Oct 17 07:22 orion_20171017_0702_mbps.csv
-rw-r--r--. 1 oracle oinstall   811 Oct 17 07:22 orion_20171017_0702_lat.csv
-rw-r--r--. 1 oracle oinstall   742 Oct 17 07:22 orion_20171017_0702_iops.csv
-rw-r--r--. 1 oracle oinstall 19494 Oct 17 07:22 orion_20171017_0702_hist.txt
-rw-r--r--. 1 oracle oinstall  2008 Oct 17 07:22 orion_20171017_0702_summary.txt










Below is the contents I extracted from orion_20171017_0700_iops.csv

file and it has more details for Small I/O and Large I/O statistics in there.

 

This comma-separated-value file contains the rates sustained by small I/Os in IOPS.

Each value corresponds to a data point test that used a fixed number of outstanding small and large I/Os.

The number of outstanding small I/Os for a value is specified by its column header in the first row.

The number of outstanding large I/Os for a value is specified by its row header in the first column.




Small I/O 4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 Large I/O 587 667 595 428 361 338 340 340 336 341 342 351 339 335 346 350 351 353 352 351





Similarly, you can review all required .csv and other files to study the evaluation in details to get an idea how your oracle database will perform on new hardware.