Search
SailfishOS Open Build Service
>
Projects
>
sailfishos
:
chum
>
collectd
> _service:tar_git:README.md
Log In
Username
Password
Cancel
Overview
Repositories
Revisions
Requests
Users
Advanced
Attributes
Meta
File _service:tar_git:README.md of Package collectd
# collectd port for Sailfish OS This is a README for Sailfish port of collectd. The port has been developed for Sailfish, but should work for other Mer-based distributions. The port includes changes in the daemon to take into account that the mobile OS is suspended frequently, provides configuration and systemd unit files with the settings that have been tuned for Sailfish. ## Using collectd Read about collectd on the main project page. Install collectd with all its dependencies. By default, the collectd daemon will be enabled and started by systemd for user nemo. Its configuration file is at /etc/collectd.conf and you have to have root permissions to edit it. However, in contrast to usual collectd.conf permissions, others can read this file as well. To avoid excessive wear of permanent storage in mobile, collectd RRD databases are stored in /tmp/collectd. Before starting the daemon, this directory is created and contents copied from /home/nemo/.local/share/collectd . After the daemon is stopped, contents of /tmp/collectd is copied back to /home/nemo/.local/share/collectd . Such movement of the collected data is performed by /usr/bin/collectd2tmpfs script that is run by systemd. One can consider adding syncing the data from /tmp/collectd if needed. For that, relevant systemd configuration files could be added by user. If you want to change the time interval used to collect the data, note that limited intervals are supported by keepalive library used in this port. All intervals are listed in the relevant code starting from https://git.merproject.org/mer-core/nemo-keepalive/blob/master/lib-glib/keepalive-backgroundactivity.h#L69 as a "BACKGROUND ACTIVITY FREQUENCY X" enum. Note that the device will be brought out from suspend at each interval. As usual for collectd, if you change the interval, delete all your collected data and start from new (if you use RRD). As a GUI for Sailfish, a new application has been written: https://github.com/rinigus/systemdatascope . This application allows to see the recorded datasets and start/stop the daemon. To analyze collected data, you could transfer it to Linux PC by using rrd-sync script provided with rrdtool package in Sailfish [packaging code is at https://github.com/rinigus/pkg-rrdtool ]. This script allows to move RRDs between different architectures by dumping them to XML and restoring on target machine (target should have rrdtool installed). After transferring the data, use GUIs developed for Linux. For example, use collectd-web with its runserver.py (adjust path in cgi-bin/collection.modified.cgi of collectd-web and make collection.conf as needed). Alternatively, https://github.com/rinigus/systemdatascope can be used in Linux as well. ## Implementation details The changes in the code were done in src/daemon/collectd.c . Instead of calling "do\_loop", glib main loop was created and used. By using keepalive library ( https://git.merproject.org/mer-core/nemo-keepalive ), background activity interval was specified and, through glib, its calling the callback function "do\_shot". In the end of "do\_shot", a continuation of the loop is requested by calling "background\_activity\_wait". Note that after calling "background\_activity\_wait", device could suspend again. The initialization, signal callbacks, and cleanup on shutdown were rewritten as well. To avoid compilation warnings, "do\_loop" is preprocessed out if HAVE\_KEEPALIVE\_GLIB is defined. As far as I understand, the main problem with the implementation is caused by multi-threaded approach to reading the data by collectd. From reading the code, I am not sure whether after exiting plugin\_read\_all all plugins have finished reading. For fully correct implementation, that should be the case. If it is not the case, it would be great if someone with knowledge of collectd would step in and help to implement this call as needed. In practice, on Nexus 4 SFOS port, every wakeup takes at least 6 seconds and within that time all plugins have been updated, as far as I could see from the graphs. ## Packaging and helper scripts for collectd in Sailfish. Here, a larger package with all selected modules included is made. If needed, additional packages can be generated with modules missing from the main package. For that, RPM spec file has to be modified. To simplify the builds, `src/liboconfig/parser.c` `src/liboconfig/parser.h` were added to sources. Thus, on updates, those files may have to be regenerated. Addition was imposed due to build errors using SDK on PC. The build required preparation of the source in full Linux PC (I used Gentoo) and building later in MER SDK. When building directly from git sources on MER SDK, I had problems with bison (google pointed to some bison bug). So, to build: * clone git repo * In full Linux host, not MER SDK, prepare the source files: * ./build.sh * configure * make -j4 * make clean * in MER SDK, make RPM as usual: * mb2 -t SailfishOS-i486 -s contrib/sailfish/collectd.spec build -j4 ## Using on other Mer-based distributions The installation script (RPM spec) uses user 'nemo' for some of its actions. This would have to be adjusted if the user name changes in Sailfish and on other Mer-based distributions.
