Determining total data reduction

You can determine the percentage of total data reduction by querying the IBM Storage Protect™ server activity log.

About this task

Look for message number ANU2526I, which displays the data deduplication statistics, as shown in the following example:

ANE4991I (Session: 67, Node: MACHINE_ORC) DP Oracle AIX ANU0599 TDP for Oracle: (5508): =>() 
ANU2526I Backup details for backup piece /adsmorc//df_727444762_116_1 (database "orcl"). 
	Total bytes processed: 9961472. Deduplicated: Yes. Bytes after deduplication: 2272805.
	Deduplication reduction: 77.18%. Compressed: Yes. Bytes after compression: 52253. Compressed by: 97.70%.
	Encryption: None. LAN-Free: No. Total bytes sent: 52253. Total data reduction: 99.48%. 
	Total processing time: 00:00:01. Throughput rate: 9728.00Kb/Sec. (SESSION: 67)

ANE4991I (Session: 67, Node: HALLEY_ORC)  DP Oracle Win64 ANU0599  TDP for Oracle: (5508): =>() 
	ANU2526I Backup details for backup piece \adsmorc\orcnt\df_727444762_116_1 (database "orcl"). 
	Total bytes processed: 9961472. Deduplicated: Yes. Bytes after deduplication: 2272805.
	Deduplication reduction: 77.18%. Compressed: Yes. Bytes after compression: 52253. Compressed by: 97.70%.
	Encryption: None. LAN-Free: No. Total bytes sent: 52253. Total data reduction: 99.48%. 
	Total processing time: 00:00:01. Throughput rate: 9728.00Kb/Sec. (SESSION: 67)

In the following example, the Oracle database backup piece size is 9,961,472 bytes. Then, it was deduplicated and the number of bytes after deduplication is 2,272,805.

The total data reduction is calculated as follows:

The percentage of data that is deduplicated is as follows:

Deduplication reduction = (1 - 2272805 / 9961472 ) = 0.7718

After data deduplication, the object was compressed. The number of bytes before compression is the number of bytes after deduplication. The data was compressed to 52,253 bytes. Therefore,
```
Compressed by  = (1 - 52253 / 2272805) = 0.9770
```
The total bytes sent to the server equals the number of bytes after compression. The formula for total data reduction is as follows:
```
Total data reduction = (1 - bytes after compression / bytes processed) 
= (1 - 52253 / 9961472) = 0.9948
```

Results

If there is no deduplication, the number of bytes after deduplication equals the number of bytes processed. If there is no compression, the number of bytes after compression equals the number of bytes after deduplication.

If you want to find out data reduction across multiple backup pieces, you can add up the numbers and calculate the ratios.

You can also use the performance monitor feature in the IBM Storage Protect server to verify the percentage of data that has been deduplicated. The performance monitor feature is part of the IBM Storage Protect Administration Center. The data deduplication statistics are displayed graphically in the Performance GUI in the Administration Center.

The following example illustrates how you can set up the dsm.sys file on AIX® to enable the performance monitor feature:

servername fvtseries2
tcps fvtseries11esx2.storage.usca.ibm.com
tcpp 1500
nodename apitest
*errorlogname /home/api/logs/tdperrs.log
errorlogname  /home/orc11r2/tdperrs.log
PERFMONTCPSERVERADDRESS jumboesx1.storage.usca.ibm.com
PERFMONTCPPORT 5129