I am not familiar with how daffodil's performance stats are reported (particularly how the average rate is faster then the max rate).
However, the biggest bottlenecks for Daffodil performance is schema compilation. If performance is a concern, I would recommend pre-compiling your parser using the `daffodil save-parser` command. You can then use the pre-compiled parser using the '-P' flag instead of '-s'. Note that Daffodil does not have a stable format for pre-compiled parsers, so the Daffodil version used to save the parser would need to match the version used to run it. A similar issue (which wouldn't be captured by daffodil performance) is startup time. Since Daffodil runs on the JVM, just starting it takes a substantial amount of time (`time daffodil --help` is about 800ms on my development system). On your actual system, I would suggest either using daffodil in stream mode, or using it as a library as part of a long-lived process. If you do either of these, them pre-compiling would help reduce your startup time, but would not offer any additional benefits to throughput. ________________________________ From: Rose, Rob P <robert.r...@gd-ms.com> Sent: Friday, November 8, 2019 10:45 AM To: dev@daffodil.apache.org <dev@daffodil.apache.org> Cc: Hanna, Maria <maria.ha...@gd-ms.com> Subject: CLI Performance usage... All, I am trying to port the Apache daffodil libraries onto an cross domain guard that runs in a very small form factor. We have cross compiled OpenJDK 12 for the aarch64 (ARM processor) and loaded into memory. I have built the source using sbt (sbt daffodil-cli/stage) and loaded the necessary jars into memory on the board. Here are some of the specifics of the hardware platform running on this guard: · 2 GB DDR RAM o Memory Management Unit (MMU) Page Tables used in this system are one-to-one mapping. · ARM Cortex A53 4 Core Processor Here are some the specifics for the software components · SELinux · Busybox Here is some of the performance numbers we are seeing from the performance testing: NOTE: These tests were run using the attached csv file and the attached schema # ./daffodil performance -s demo/csv.dfdl.xsd -N 100 -t 5 demo/test_file.csv total parse time (sec): 2.443824 · What does the total parse time value mean ? · How is it calculated ? · Is this poor performance? min rate (files/sec): 1.535568 · What is the min rate (files/sec) What does this mean ? max rate (files/sec): 29.460340 · What is the max rate (files/sec) What does this mean ? avg rate (files/sec): 40.919485 · What is the avg rate (files/sec) What does this mean ? · Do you have any suggestions how to improve parse/unparsed speed on an ARM processor? · Any suggestions are greatly appreciated! # ./daffodil performance -s demo/csv.dfdl.xsd -N 200 -t 5 demo/test_file.csv total parse time (sec): 3.175893 min rate (files/sec): 1.520884 max rate (files/sec): 107.223428 avg rate (files/sec): 62.974409 # ./daffodil performance -s demo/csv.dfdl.xsd -N 300 -t 5 demo/test_file.csv total parse time (sec): 3.656587 min rate (files/sec): 1.551273 max rate (files/sec): 180.155186 avg rate (files/sec): 82.043712 # ./daffodil performance -s demo/csv.dfdl.xsd -N 1000 -t 5 demo/test_file.csv total parse time (sec): 5.602554 min rate (files/sec): 1.459977 max rate (files/sec): 301.144046 avg rate (files/sec): 178.490026 Sincerely, Rob Rose Sr. Principal Software Engineer General Dynamics Mission Systems Office: 508-880-1866 Cell: 508-341-5216 This message and/or attachments may include information subject to GD Corporate Policies 07-103 and 07-105 and is intended to be accessed only by authorized recipients. Use, storage and transmission are governed by General Dynamics and its policies. Contractual restrictions apply to third parties. Recipients should refer to the policies or contract to determine proper handling. Unauthorized review, use, disclosure or distribution is prohibited. If you are not an intended recipient, please contact the sender and destroy all copies of the original message.