TEMS vs. TEMA

When configuring historical database collection for an attribute group you have the option to store the raw binary files on the TEMA (i.e., the managed system) or on the TEMS. In my early discussions with some of the TDW architects it was suggested that storing data on the TEMS for larger implementations was a bad idea. I have posted this question on Developerworks and there appears to be no clear response from IBM. I will try to list some of the pros and cons in this article and leave the thread open for further discussion.

(Storing data on the TEMS):

Storing historical data on the TEMS is ideal for agents beyond a firewall. NOTE: This should be addressed when 'multiple WPA's in a HUB'support is available.

It is easier to monitor disk usage on a few servers rather than 100's. For example, if the WPA stops running or can't keep up the TEMA's file systems may file up on you managed systems and may be harder to detect or even worse be notified by the sysadmin.

Shortened path to get to the data. When looking at 24 hour or less data the TEPS request doesn't have go all the way down to the TEMA.

Less impact on the managed system from a performance perspective.

Don't have to deal with the 1500 (logical RPC connection) issues with the WPA Windows server. NOTE: This should also be addressed when 'multiple WPA in a HUB'support is available.

(Storing data on the TEMA):

When you store historical data on the TEMS is creates one table for all agents for each attribute group. If you start collecting more than a couple of hundred agents from one TEMS access to this table may be a performance issue.

Less overhead on the TEMS.