General DB2  Devices Tapes Consider the following general recommendations when you work with OAM for Content  Manager OnDemand: Consider the following list of recommendations that relate to DB2: Consider the following recommendations that relate to devices: Consider the following recommendations that relate to tapes: GLYPH<SM590000> Define a user catalog exclusively for collection names. GLYPH<SM590000> Cache the user catalog in the virtual lookaside facility (VLF). GLYPH<SM590000> Migrate objects to optical or tape (OSMC) during non-peak hours. GLYPH<SM590000> Spread OAM collections over multiple DB2/disk/channels. GLYPH<SM590000> Spread out the application groups to different collection names:  GLYPH<SM590000> Group your applications based on retrieval expectations: – Collect small, frequently used applications together. – Isolate your important applications so that the other applications do not get in the way. OAM collections  storage groups  DB2 database GLYPH<SM590000> Ensure that enough DB2 connections are available to support the OAM requests.  GLYPH<SM590000> Run the  REORG ,  RUNSTATS , and  REBIND  commands, as appropriate. GLYPH<SM590000> Partition OAM table spaces larger than 2 GB. GLYPH<SM590000> Determine and set the Initial Access Response Seconds (IARS) option. GLYPH<SM590000> Assign objects to storage classes that have an adequate IARS that is defined and to  management classes that do not cause a transition to a slower storage class until the  frequency of retrieving the objects is reasonably low. GLYPH<SM590000> Determine whether to place the object on disk or removable (optical or tape) media. GLYPH<SM590000> If the IARS opts for REMOVABLE media, determine whether to place the object on optical  or tape. GLYPH<SM590000> Verify that the required Sustained Data Rate is achieved based on the selected object  placement. GLYPH<SM590000> Modify (CBROAMxx)  MAXTAPERETRIEVETASKS  and  MAXTAPESTORETASKS  (if you are using tape  retrieves because the default=1). Both of these parameters are configured at the global  level and at the storage group level.  GLYPH<SM590000> The global level  MAXTAPERETRIEVETASKS  (tasks) is defined by  SETOAM .  SETOAM  specifies the  total number of concurrent tape retrievals that are possible at a time. (It controls the  maximum number of tape drives that can be concurrently allocated to the OAM address  space for reading object data from tape.) This number must be less than or equal to the  number of tape drives on the system. Do not specify a number that is greater than the  number of tape drives that are available to OAM for the  MAXTAPESTORETASKS  or the  MAXTAPERETRIEVETASKS  subparameters because a system can go into allocation recovery  and attempt to allocate tape drives after all of the tape drives are in use, causing system  problems. GLYPH<SM590000> The storage group level  MAXTAPERETRIEVETASKS  (tasks) specifies the maximum concurrent  tape retrievals that are possible for a specific storage group. If  MAXTAPERETRIEVETASKS  is  Chapter 5. Storage management  111