Documentation

Tools for servers management

The aquosa-qosres component includes a couple of useful tools, namely qres-wrap and qres.

The first tool is available for historical reasons that date back to the OCERA project, and constitutes a quick way to wrap an entire application within a sof reservation. The command

$ qres-wrap <max_bdg> <min_bdg> <period> <prog> <options>

$ qres-wrap 75000 0 100000 /etc/init.d/tomcat start

The most useful tool is the new qres command, that allows a complete management of the servers and attached threads/tasks, through a command-line interface. As easily guessable from the help page, it is possible to create and destroy servers, attach and detach threads, change and retrieve server parameters.

tommaso@mobiletom:~/aquosa/website$ qres -h
Usage: -h [ options... ]
  -q-min Q_min : set minimum guaranteed budget per server period
  -q Q_max     : set required budget per server period
  -p P         : set server period
  -f flags     : set flags
  -pid pid     : set process id to affect or 0 for self (defaults to tid)
  -tid tid     : set thread id to affect or 0 for self (defaults to pid)
  -sid sid     : set id of existing server to affect
  -create      : create server (requires q, p, q_min=0)
  -destroy     : destroy server (requires sid)
  -attach      : attach thread to server (requires sid, pid, tid)
  -detach      : detach thread from server (requires sid, pid/tid)
  -setparams   : set server params (requires sid, q, p, q_min=0)
  -getparams   : get server params (requires sid or pid/tid)

Sample usage   : qres -create -q 10000 -p 30000 -attach -tid 44021
Altern. syntax : qres create q=10000 p=30000 attach tid=44021

Also, consider looking at the information in

- /proc/aquosa/qres/scheduler
- /proc/aquosa/qres/tasks