Project Status Update No. 9

Welcome to the precached project status update No. 9!

In this cycle we mainly concentrated on stabilizing the project and on preparing the 1.2 release.

What has been achieved

All external dependencies have been updated to their latest versions. Additionally the big i18n support patch has landed. We added localizations for the english and german languages. Most user visible strings have been translated. Translation of error and other log messages still remains to be done.

precached-debug

The project gained a new debugging tool called precached-debug. It may be used to exercise the I/O tracing subsystem of precached. For now it supports the creation and subsequent accessing of files.

Memory consumption analysis

The companion tool iotracectl learned to calculate memory consumption informations for I/O trace logs. It can be used to analyze which I/O trace logs, and subsequently which files contribute the most to the overall memory usage of the precached daemon. For instance the command iotracectl sizes --executable=firefox will show the amount of memory that will be consumed if the files recorded in the I/O trace logs of the firefox executable get loaded into the cache.

Introspection

We added an introspection feature to the precached daemon. The companion tool precachedctl gained the ability to show this introspection data. The command precachedctl plugins analyze internal-state will print a tabular view of key and value pairs, showing the most important internal state parameters of the running precached process. Additionally a warning level indicator is displayed, which indicates if the value is in nominal range.

Runtime Profiles

The daemon now supports switching between different profiles. For now, we added the two profiles: BootUp and UpAndRunning. After the daemon has been started it enters the BootUp profile, where only online-prefetching will be performed. Offline-prefetching will be activated after precached-trigger transition-profile got executed, and the daemon transitioned to the UpAndRunning profile. To put it simple, offline-prefetching will now be started as soon as the user logs into the desktop. We supply a .desktop file that gets installed in the xdg-autostart directory. It runs the aforementioned precached-trigger transition-profile. This leads to somewhat faster boot times, since the prefetching is postponed to a later stage of the system’s start-up process.

The precached team