Tool 2 Highlights
This page contains some highlights from a root file usage file parsed by Tool2.
The following three graphics show the variety of file access patterns that can be identified using the raw_reads images output for each root file.
This image displays a file that was read pretty well using Root. Few locations had a backtrack when reading the file.
This image displays a file that the ROOT framework had a hard time reading in sequential order. There are quite a few backtracks throughout the whole file.
This image displays an interesting file usage pattern. The Root framework performed somewhat well on the whole file. But in some locations the file was read with many backtracks highlighted by the stars on the graphic. The reads in those 6 locations are very dense.
The image below shows and instance where the file reads matched the branches very well in some locations and poorly in others.
The following images show how the tool can be used to examine a file.
A person examining the raw reads output by the tool in bulk may become interested in a file for a variety of reasons. In this instance they may want to examine the first couple of MB on this file.
Examing the overlaid graphic they see that the root file has many small branches that are being read. Using the regular expression filter provided in Tool2 they can than produce a variety of different graphics that examine this file in different ways.
Here they expand the size of the window to see if they can determine any interesting areas that warrant further examination.
After examining the 40mb window they decide to look at the first 10mb of the file to see the smaller details it contains. However, the first 100 reads in the file are nearly in a continuous block and not interesting to the user. And they decide to produce the graphic after the first 100 reads have been encountered sequentially in the file.
The command line options for Tool2 allow the user to change the size and starting position of the window so they can better see the file reads.