Evaluation1 - SB Experiment Audio mp3 to wav Migration and QA on Hadoop Cluster

Evaluator(s)

Bolette Jurik (SB)

Evaluation points

Assessment of measurable points

*Based on the small experiment with max split size 128 below. See explanation for the abysmal correctness score.

Small Experiments

All run on a file list of 58 files (7.2Gb in total).

The big question is why we get so many failures? The answer is of course that the list of pairs of files to compare is wrong! This list is created by Taverna beanshells, and we are missing a sort of the two output lists from the FFmpeg and mpg321 Hadoop jobs, before we combine the lists to a list of pairs as input to the waveform-compare Hadoop job. This should be a fairly quick fix...

The exact number of MR maps seem not to have a big influence on performance, as long as we have more than 12. That is as long as max split size is at most 256. We note that we get approximately twice as many launched maps for the waveform-compare Hadoop job, simply because the input list is approximately twice as big, as it is a list of pairs. We can of course adjust this to get approximately the same number of jobs, but it does not seem to be important for the performance.

The first line of tests were to decide on expected optimal max split size.

The next line of tests will use 128 as max split size and vary on the size of the input

Assessment of non-measurable points

ReliableAndStableAssessment Reliability - Runtime stability

For some evaluation points it makes most sense to a textual description/explanation

A note about goals-objectives omitted, and why

This evaluation covers performance, reliability and functional suitability to some extent_._ We did not look at the metrics MaxObjectSizeHandledInGbytes and MinObjectSizeHandledInMbytes. These measures would certainly contribute to the evaluation. Our collection ([Danish Radio broadcasts, mp3|../../../../../../../../../../display/SP/Danish+Radio+broadcasts%2C+mp3]) has mp3 files varying very little in size (approx. 2 hours, average file size 118Mb, largest file: 124Mb) and the workflow thus produces wav files varying very little in size (around 1.4Gb *2 per mp3 file). The test mp3 files used under development were of course considerably smaller (around 7Mb) and produced smaller output (around 50Mb*2 per mp3 file).

We did also not look at the metrics ThroughputGbytesPerMinute, ThroughputGbytesPerHour, or AverageRuntimePerItemInHours. These are all possible to compute fairly easily though.

WORK IN PROGRESS

The evaluation does not cover

• Organisational maturity
• Maintainability
• Planning and monitoring efficiency
• Commercial readiness

Technical details

Remember to include relevant information, links, versions about workflow, tools, APIs (e.g. Taverna, command line, Hadoop, links to MyExperiment, link to tools or SCAPE name, links to distinct versions of specific components/tools in the component registry)

WebDAV

We would like to store sufficient information about an experiment (hadoop program, configuration, etc.), so we are able to rerun it. For this purpose, ONB is providing a WebDAV - if you have questions and need more information, please contact Sven or Reinhard at ONB.
Taverna workflows will still be stored on myexperiment.org.

Link: http://fue.onb.ac.at/scape-tb-evaluation

Please use the following structure for storing experiment results

Evaluation notes

Could be such things as identified issues, workarounds, data preparation, if not already included above

QAFalseDifferentPercent