# Issues with large files¶

## Data expansion issues¶

NMRPipe is currently a 32-bit program and, as such, there are limitations to the size of the file it can read, write, and access in memory. For example, a Bruker 4D NUS ser file that is expanded to a final size of 2048 $$\times$$ 96 $$\times$$ 128 $$\times$$ 96 (t4, t3, t2, t1) will produce a file that is approximately 9.7 GB. Converting this file to NMRPipe format with bruk2pipe is problematic for many 32-bit versions of NMRPipe [*].

The file size limit as well as the indication that an expansion has failed may vary with system. Besides the existence of a large data set, one indication of a problem is that the bruk2pipe (and presumably also var2pipe) command simply stops during conversion producing an error message similar to this:

DATAIO File Read Error 0.
Request: 786432 Actual: 524287.

The file size limit also can cause issues with Sparky where 32-bit versions of pipe2ucsf are unable to convert NMRPipe data to the format used by Sparky. In our experience, these issues are solved by switching to a 64-bit version of the program. For Linux, such a version is available from the Sparky website. For Mac OS X, a 64-bit version is available from the NMRFAM website or it can be compiled using the MacPorts package manager.