Currently, the maximum file size that parses successfully for CSV is 250MB. A 300MB file failed with the following error:

edu.illinois.ncsa.daffodil.exceptions.Abort: Usage error.
edu.illinois.ncsa.daffodil.exceptions.Assert$.abort(Assert.scala:95)
edu.illinois.ncsa.daffodil.exceptions.Assert$.usageErrorUnless(Assert.scala:71)
edu.illinois.ncsa.daffodil.exceptions.Assert$.usage(Assert.scala:62)
edu.illinois.ncsa.daffodil.processors.InStreamFixedWidthTextOnly.atCharPos(InStreamTextOnly.scala:107)
at edu.illinois.ncsa.daffodil.exceptions.Assert$.abort(Assert.scala:95)
at edu.illinois.ncsa.daffodil.exceptions.Assert$.usageErrorUnless(Assert.scala:71)
at edu.illinois.ncsa.daffodil.exceptions.Assert$.usage(Assert.scala:62)
at edu.illinois.ncsa.daffodil.processors.InStreamFixedWidthTextOnly.atCharPos(InStreamTextOnly.scala:107)