Help: unable to get debugging information for native mode

[SimoA88]

Hi, i'm a new user to memray so i apologize in advance if my question is silly.
I'm following the "hands on tutorial" but i'm having problems with exercise 3: despite having installed debuginfod and having set the enviroments variables my flamegraph remain full of <unknown> at <unknown>;0.

Setting DEBUGINFOD_PROGRESS=1 and DEBUGINFOD_VERBOSE=1 and running memray flamegraph produce an output like:

Trying to download debuginfo for /proc/self/exe
debuginfod_find_debuginfo 37451b37c71cb46f8ccb27cb3cdbb7aa004b9987
server urls "https://debuginfod.ubuntu.com"
checking build-id
checking cache dir /home/myhome/.cache/debuginfod_client
not found No such file or directory (err=-2)
⚠ No debug information was found for the Python interpreter ⚠

Without debug information reports showing native traces may not include file names and line numbers. Please use an interpreter built with debug symbols for best results. Check
https://bloomberg.github.io/memray/native_mode.html for more information regarding how memray resolves symbols.

⠋ Processing allocation records... ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 0% -:--:--Trying to download debuginfo for /usr/bin/python3.12
debuginfod_find_debuginfo 37451b37c71cb46f8ccb27cb3cdbb7aa004b9987
server urls "https://debuginfod.ubuntu.com"
checking build-id
checking cache dir /home/myhome/.cache/debuginfod_client
not found No such file or directory (err=-2)
[...]
Wrote memray-flamegraph-lru_cache.py.7735.html

Am i doing something wrong? Or for some reason debuginfod is unable to locate the informations?
Thank you in advance.

Setup:

• Ubuntu 24.04.2
• Python 3.12.3 in a virtual enviroment with the packages listed in requirements-tutorial.txt
• Packages installed:

Package Version
----------------- -------
astroid 3.3.9
dill 0.3.9
iniconfig 2.1.0
isort 6.0.1
Jinja2 3.1.6
linkify-it-py 2.0.3
markdown-it-py 3.0.0
MarkupSafe 3.0.2
mccabe 0.7.0
mdit-py-plugins 0.4.2
mdurl 0.1.2
memray 1.16.0
numpy 2.2.4
packaging 24.2
pip 24.0
platformdirs 4.3.7
pluggy 1.5.0
Pygments 2.19.1
pylint 3.3.6
pytest 8.3.5
pytest-memray 1.7.0
rich 13.9.4
textual 2.1.2
tomlkit 0.13.2
typing_extensions 4.12.2
uc-micro-py 1.0.3

[godlygeek]

Hm. It's odd that we're not seeing any HTTP requests in the verbose log. I'm not actually sure what could cause that... It clearly has loaded the debuginfod library, but it never seems to reach the point of making the HTTP requests. If it did, the HTTP request to https://debuginfod.ubuntu.com/buildid/37451b37c71cb46f8ccb27cb3cdbb7aa004b9987/debuginfo should succeed - at least, that URL is valid and does resolve to debug info.

I guess you've censored your username in /home/myhome/.cache/debuginfod_client?
What do you see if you ls -l ~/.cache ?
How about if you ls -l ~/.cache/debuginfod_client ?

The only thing I can think of that might make it so that "No such file or directory" is a fatal error in that context is if the debuginfod_client cache directory not only doesn't exist, but also can't be created because the user you're running Memray as is a different user than the user that owns /home/myhome or than the user that owns /home/myhome/.cache - maybe the .cache directory got created with root as the owner due to something being run with sudo without changing $HOME, or something like that, and now things running as your regular user are no longer able to create cache entries.

[SimoA88]

Thanks for the answer.

I've removed the username although this was probably unnecessary.
.cache contain debuginfod_client folder .
Runnning ls -l ~/.cache/debuginfod_client i get the filescache_clean_interval_s and cache_miss_s and a list of folders named like build ids (e.g. : 37451b37c71cb46f8ccb27cb3cdbb7aa004b9987)
Each one of those folders contain a file named debuginfod witch is empty. Removing those folders and running memray again populate the debuginfod_client folder in the same way as before.
I'll try to play a bit with permissions although it seems that debuginfod was able to create the cache and is able to write inside of it and i' m executing memray from the same user that installed debuginfod and owns the cache folder.