Solution
When acquiring data at higher rates and logging them to file, NI recommends using a TDMS file format (per The NI TDMS File Format) to increase your application's performance. This is due to writing data to an ASCII file being significantly slower compared to other formats. In many cases, the write speed of an ASCII file cannot keep up with the speeds of acquisition systems, which can lead to data loss. Meanwhile, TDMS is a binary-based file format, so it can stream data to disk at high speeds and also has a small disk footprint.