Installing uDAPL

The User-level Direct Access Programming Library (uDAPL) version 2.0 is supported by the AIX operating system.

The uDAPL installation image is shipped on the expansion pack as udapl.rte. This image ships the DAT header files, which are located in the /usr/include/dat directory. The installation image also ships the libdat.a and libdapl.a libraries.

Applications include the DAT header files and link with the libdat.a DAT library in the /usr/include/dat directory. The DAT layer determines the appropriate underlying transport-specific libraries.

An AIX uDAPL provider registers itself with the DAT registry by using the dat.conf file entries. The /etc/dat.conf file is shipped with default entries and the file has details on the format of the entry.

The uDAPL libraries support the AIX system trace for debugging events. The uDAPL system trace connects ID that includes 5C3 (for DAPL events), 5C4 (for DAPL error events), 5C7 (for DAT events), and 5C8 (for DAT error events). The initial trace level is modified by using the DAT_TRACE_LEVEL and DAPL_TRACE_LEVELenvironment variables. These environmental variables accept values in the 0 - 10 range. The number of events and amount of data traced increases with the key trace levels as follows:

 TRC_LVL_ERROR  = 1
 TRC_LVL_NORMAL = 3
 TRC_LVL_DETAIL = 7

Other standard AIX serviceability features, such as the AIX error log are used to identify problems when tracing an event. The serviceability features of the underlying transport layer, such as the ibstat command and InfiniBand component trace, are also helpful for analyzing the issues.

The DAT APIs return the standard return codes that can be decoded by using the /usr/include/dat/dat_error.h file. The detailed explanation about the return codes is provided in the uDAPL specification from the DAT Collaborative.