asset tracking template
Two approaches prevail in the discussion about the client implementation. It can either
be implemented as a shared library (Unix) or Dynamic Link Library (DLL) (Windows) in
the asset tracking template or as a kernel module. In the user space variant - known as
uDAFS - the DAFS library instructs the kernel to set up an exclusive end-to-end connection
with the DAFS server for each system call (or for each API call under Windows) by
means of a VI provider layer (VIPL), which is also realised as a library in user space. The
VI-capable NIC (VI-NIC) guarantees the necessary protection against accesses or faults
caused by other processes. The user space implementation can utilise the full potential
of DAFS to increase the I/O performance because it completely circumvents the kernel.
It offers the application explicit control over the access of the NIC to its private storage
area. Although control communication takes place between the VIPL in the user space
and the VI-NIC driver in the kernel, the CPU cost that this entails can be disregarded due
to the low data quantities.
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