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zypper install tab-completion

June 6th, 2015 by

This is a follow-up on my earlier post on zypper tab-completion.

Completion for package-names just made its way into git (thus soon will appear in Factory aka Tumbleweed) after ~6 weeks of back and forth exploring different approaches.

And it is super-fast 🙂

If you do not want to wait, you can use OneClickInstallCLI http://multiymp.zq1.de/zypp:Head/zypper
with allowing some vendor changes for libzypp and libsolv

zypper tab-completion and some thoughts

April 26th, 2015 by

Today I spent some hours implementing nice tab-completion for zypper. There was already a lot done 6 years ago, but the part about installing/removing packages was missing.

Now the thinking part is about the speed. For the tab-completion I needed a list of installed packages and of course we have that in our RPM database (using berkeley DB as a backend). However querying the list with rpm -qa already took over a second on a modern and fast system. On my poor netbook with a cold cache, it took 25 seconds (5 secs on second try with hot cache)… And the point is that you probably do not want to wait 5 seconds for your tab-completion to react.

So to avoid this problem, I used caching via make to produce a better format (plain text). This is then post-processed with sed in a fraction of a second – a speedup factor somewhere between 15 and 150. This makes a big difference.

In the end, I still wonder why plain text is so much faster than a DB. I guess, one reason is that the DB is optimized for retrieval of single values – e.g. rpm -q bash – this is very fast (but even there an egrep “^bash-[^-]+-[^-]+$” is more than twice as fast).

I still want to optimize zypper for better speed, so that a search might some day return in under 2 seconds. One idea for that is to not parse all those config+repo files every time, but only when they change. It could use mmaped files under /var/cache/zypp* as memory to store the binary representations. Though it might become complicated, if dynamic structures such as linked lists are involved.

The future will be interesting…

Is my server alive and how good is my connection

March 10th, 2014 by

If you have time to setup real solution and need something reliable test Zabbix (http://zabbix.com). Zabbix is wonderful all in one solutions for monitoring network and your hosts (servers). If you are in need of knowing how good you Internet/(W)LAN connections is then things are getting complicated. (more…)