Running DiskSim 4.0 On 64-Bit Ubuntu

DiskSim is a disk simulation software used for I/O analysis research. It is used as a research tool instead of a commercial tool, and hence requires some tweaking to run on your system.

This is a guide to installing and running DiskSim 4.0 on 64-bit Ubuntu machines. 64-bit machines require a patch, as DiskSim is originally intended for 32-bit machines. Also, some changes need to be made to certain Makefiles. Without making the changes, the compilation of the DiskSim code fails.

Firstly, download the 64-bit patched code for DiskSim 4.0 as a zip file from the following GitHub repository: DiskSim 4.0

Unzip the contents into any directory. For convenience, use the user home folder (as has been done in the following example for the rest of this post).

Now, cd into the directory disksim-4-0-x64-master from the terminal. When you run ls, you should see a list of folders such as diskmodel, doc, etc.

The libddbg, libparam, and diskmodel directories require no changes to be compiled correctly. However, memsmodel and src directories will require a few modifications to work correctly. So, run the following commands in sequence:

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Diversity in Smartphone Usage

This is a short summary or overview I wrote after reading a conference paper from the ACM Digital Library. The original paper can be found here: Click here

Diversity in Smartphone Usage

Experimental Setup

A study was conducted to analyse the variation in smartphone use across a variety of users. Detailed usage traces were collected from 255 users, grouped into two datasets.

Dataset 1 – Consisted of 33 Android users out of which 17 were research workers and 16 were students. A custom logging utility was deployed on HTC Dream smartphones with unlimited plans. The logger collected detailed data such as the state of the screen, start and end times of calls, application interaction time, network traffic, and battery level. 7-21 weeks of data was gathered per user, with the average being 9 weeks. The logger ran in the background, keeping data records in a local SQLite database on the phone, and uploading them only when the phone was being charged.

Dataset 2 – Consisted of 222 Windows Mobile users across different demographic and geographic locations. The demographic categories were: SC (social communicators; required voice and text), LPU (life power users; needed a multi-function device), BPU (business power users; needed advanced phone for business), OP (organiser practicals; needed a simple device for management). 8-28 weeks of data was gathered per user by a third party, with the average being 16 weeks. Traces were collected using a logger that recorded start and end times of applications using API calls.

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Analysis of I/O Behaviour of Apple Desktop Applications

This is a short summary or overview I wrote after reading a conference paper from the ACM Digital Library. The original paper can be found here: Click here

Analysis of I/O Behaviour of Apple Desktop Applications

Experimental Setup

The iBench task suite was created consisting of 6 applications running a total of 34 different tasks. The applications were grouped as iWork (Pages, Numbers, Keynote) and iLife (iPhoto, iTunes, iMovie). The I/O behaviour of these applications was analyzed.

The tasks in the iBench suite were:

  • iLife iPhoto: start, import, duplicate, edit, view, delete. The application worked on 400 2.5 MB photos imported as 12 MP pictures from a 1 GB flash card.

  • iLife iTunes: start, import and play mp3 album containing 10 songs, import and play a 3 minute long MPEG-4 movie.

  • iLife iMovie: start, import, add clip to project, export to 3 minute MPEG-4 movie.

  • iWork Pages: start, create, save, open, export 15 page documents with and without images in different formats.

  • iWork Numbers: start, generate and save, open, export a 5 page spreadsheet.

  • iWork Keynote: start, create slides with and without images, open, play, export 20 slides.

For the purpose of a particular case study, the Pages application, a word processor, was used to create a blank document, insert 15 JPEG images each of size 2.5 MB, and save as .doc.

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