I have had a number of customers lately call me to complain about restores of a single directory on a large file server running for many hours without transferring any data. In each case I have suggested they use

TESTFLAG DISABLENQR

Each time the next restore would run in minutes.

Many of you know that this simply changes the restore from the post TSM 3.1 “No Query Restore” back to the older “Classic” restore.

Do not use client dedup nor compression if you backup on containers. Data reduction on client side will preserve your bandwith, but ask to TSM admin before.

• TCPWINDOWSIZE: Specifies the size, in kilobytes, to use for your client node TCP/IP sliding window. The range of values is 0 through 2048. A value of 0 allows the client to use the operating system default TCP window size. Values from 1 to 2048 indicate that the window size is in the range of 1KB to 2MB. If you specify a value less than 1, the TCP window size defaults to 1. If you specify a value greater than 2048, the TCP window size defaults to 2048.

For backup-archive clients, the default value for this parameter is 63 KB on AIX and Solaris. And 0, the OS default, on the other platforms Linux, Windows and Mac. For IBM Spectrum Protect for Virtual Environments: Data Protection for VMware, the default value for this parameter is 512 KB.

• RESOURceutilization: Specifies the level of resources the IBM Spectrum Protect server and client can use during processing. The range of values that you can specify is 1 - 100. The default value is 2.

• TCPBuffsize: The tcpbuffsize option specifies the size of the internal TCP/IP communication buffer used to transfer data between the client node and server. Although it uses more memory, a larger buffer can improve communication performance.

The best way to find the best parameter is using command line like this:

C:\Users\admin> dsmc ba c:\tmp\my_big.iso -resourceutilization=10 -tcpwindowsize=32 

Backup-Archive client with limited, high latency network (WAN backups):
===============================
TCPWINDOWSIZE           512
RESOURCEUTILIZATION     4
COMPRESSION             Yes
DEDUPLICATION           Yes
ENABLEDEDUPCACHE        Yes

Tip: Do not use the client deduplication caching for applications that use the IBM Spectrum Protect API (TDP).

Backup/Archive client or Client API with limited network (Gigabit LAN backups):
===============================
TCPWINDOWSIZE           512
RESOURCEUTILIZATION     10
COMPRESSION             Yes
DEDUPLICATION           Yes
ENABLEDEDUPCACHE        No

Backup/Archive client or Client API with high speed network (10 Gigabit LAN backups)
===============================
TCPWINDOWSIZE           512
RESOURCEUTILIZATION     10
COMPRESSION             No
DEDUPLICATION           No
ENABLEDEDUPCACHE        No

• TCPBUFFSIZE: The tcpbuffsize option specifies the size of the internal TCP/IP communication buffer used to transfer data between the client node and server. Although it uses more memory, a larger buffer can improve communication performance. Specifies the size, in kilobytes, that you want to use for the internal TCP/IP communication buffer. The range of values is 1 through 512; the default is 32. Depending on the operating system communication settings, your system might not accept all values in the range of 1 through 512.

Adding the following options into tdpsql.cfg from TDPsql folder will reduce backup time from 11 hours to 1 hour

BUFFers     4
SQLBUFFers  4
STRIPes     4

Higher values can be tested:

Buffering is only used on legacy mode.

The number of buffers that Data Protection for SQL allocates to the read and write threads can be specified in the /buffers (3 by default) and /sqlbuffers (0 by default) parameters of the command line interface. The size of these buffers can be specified in the /buffersize (1024 by default) and /sqlbuffersize (1024 by default) parameters. In addition to this /Stripes (1 by default) parameter determines the number of sessions in TSM Servers.

For example, you can use these parameters in your tdpsql.cfg file to backup SQL databases with 5 sessions;

BUFFers 10
BUFFERSIze 8192
STRIPes 5
SQLBUFFers 32
SQLBUFFERSIze 4096

On Spectrum Protect server also change the maximum monut points

upd node <node_name> maxnummp=10

• /SKIPINTEGRITYCHECK : Performance can improve with this parameter to bypass integrity checking. There is a risk that is associated with using this parameter.
• For VSS backups, the RESOURCEUTILIZATION client option is also important. This option increases or decreases the ability of the client to create multiple sessions. The higher the value, the more sessions the client can start. The range for the option is from 1 to 10.
• /MINimumbackupinterval=numberOfMinutes : If you are scheduling the backup of databases in an Exchange Server Database Availability Group, specify the minimum amount of time, in minutes, before a backup of another copy of the same Database Availability Group database can begin. The range is 1 - 9999