[systemd-devel] Performance of systemctl status tab completion

[Filipe Brandenburger]

On Thu, Jun 18, 2015 at 11:54 AM, Lennart Poettering
<lennart at poettering.net> wrote:
> On Tue, 02.06.15 12:18, Chris Morgan (chmorgan at gmail.com) wrote:
>> systemd 216 here on an embedded arm system, 1ghz with a load of 60% or
>> more. I enabled tab completion, because I really don't like to type,
>> and quickly found out that something like:
>>
>> systemctl status xx<tab tab>
>>
>> Takes a really long time to complete. In some cases something like 20+ seconds.
>
> Hmm, I figure we rely on some more profiling info from you to do
> something about this, i.e. is this io bound or cpu bound? It would be
> good to get some data from the "perf" tool for this.

BTW, you probably don't need to go all the way down to using "perf" to
get profiling data, just use a "set -x" on your shell which will
expand the commands it's running for completion so you might be able
to spot where the bottleneck actually is...

HTH,
Filipe