Debugging start-up time of mtda-cli

[jan-kiszka]

On my RPi4 - which is not really a slow device - I'm facing several seconds of delay between calling mtda-cli and getting the prompt. With debug=4, it takes almost 4 s to get the first output ("# debug3: main.load_remote_config()"). I also tried removing all drivers from the local config, but that had no impact.

Any suggestions how to debug this further?

[chombourger]

is that with HEAD?

[jan-kiszka]

Not yet, still on b92d55b (with Debian). I don't see "suspicious" commits since - do you expect differences?

[chombourger]

me neither - was just curious to understand which "version" you were running. I will build and flash the Pi4 image

[chombourger]

finally going to take a look

[chombourger]

Reproduced on Pi4 using the following command:

root@mtda:/home/mtda# (echo start && mtda-cli -d -n 2>&1) | ts '[%Y-%m-%d %H:%M:%S]'
[2022-12-09 00:02:52] start
[2022-12-09 00:02:55] # debug3: main.load_timeouts_config()
[2022-12-09 00:02:55] # debug3: main.load_timeouts_config: None
[2022-12-09 00:02:55] # debug3: main._parse_script()
[2022-12-09 00:02:55] # debug3: main._parse_script(): scripts.power_on()
[2022-12-09 00:02:55] # debug3: main._parse_script()
[2022-12-09 00:02:55] # debug3: main._parse_script(): scripts.power_off()
[2022-12-09 00:02:55] # debug3: main.start()

and a minimalistic config:

root@mtda:/home/mtda# cat /etc/mtda/config
[main]
debug=3

[chombourger]

reaching main() takes 3s alone as shown below:

root@mtda:/home/mtda# (echo start && mtda-cli -d -n 2>&1) | ts '[%Y-%m-%d %H:%M:%S]'
[2022-12-09 00:08:04] start
[2022-12-09 00:08:07] ### main

[chombourger]

used python3 -X importtime to check import times and self [us] for mtda.main is 1476358 (~1.5s)

[chombourger]

the overall import time is 2649476 (~2.5s)

[fmoessbauer]

I debugged this as part of f61f2fa, citing:

The startup of the mtda service might take quite long on the nanopi-neo
board (~15sec). This is due to the loading of a ton of dependencies,
which cannot really be avoided.

The mtda-cli is affected as well, as it internally loads MTDA to get the (local) MTDA version. This can be speed up by generating the .pyc files (by executing it once as root), but it is still slow. IMHO, the whole import should be made more dynamic and ideally the dependency to MTDA itself could be avoided.