Re: caching failed lookups of debuginfo?

[Aaron Merey <amerey@redhat.com>]

Hi Milian,

On Fri, Apr 8, 2022 at 5:08 PM Milian Wolff <mail@milianw.de> wrote:
> I can reproduce it now suddenly with debuginfod-find too:
>
> ```
> $
> debuginfod-find debuginfo 85766e9d8458b16e9c7ce6e07c712c02b8471dbc
> debuginfod_find_debuginfo 85766e9d8458b16e9c7ce6e07c712c02b8471dbc
> server urls "https://debuginfod.archlinux.org/"
> checking build-id
> checking cache dir /home/milian/.cache/debuginfod_client
> using timeout 90
> init server 0 https://debuginfod.archlinux.org/buildid
> url 0 https://debuginfod.archlinux.org/buildid/
> 85766e9d8458b16e9c7ce6e07c712c02b8471dbc/debuginfo
> query 1 urls in parallel
> server response HTTP response code said error
> url 0 The requested URL returned error: 404
> not found No such file or directory (err=-2)
> Server query failed: No such file or directory
> ```
>
> I do see an empty `/home/milian/.cache/debuginfod_client/
> 85766e9d8458b16e9c7ce6e07c712c02b8471dbc/debuginfo` file. But the server is
> still queried (i.e. rerunning the above command always produces the same
> output for me). The lookup is costly too at ~70ms overall:

I am not able to reproduce this on Fedora 35 using commit 8db849976f070.

The first time I run debuginfod-find I get similar output to you:
```
debuginfod_find_debuginfo 85766e9d8458b16e9c7ce6e07c712c02b8471dbc
server urls "https://debuginfod.archlinux.org/"
checking build-id
checking cache dir /home/amerey/.cache/debuginfod_client
using timeout 90
init server 0 https://debuginfod.archlinux.org/buildid
url 0 https://debuginfod.archlinux.org/buildid/85766e9d8458b16e9c7ce6e07c712c02b8471dbc/debuginfo
query 1 urls in parallel
server response HTTP response code said error
url 0 The requested URL returned error: 404
not found No such file or directory (err=-2)
Server query failed: No such file or directory
```

But when I rerun debuginfod-find I get output indicating that the cache was
checked:
```
debuginfod_find_debuginfo 85766e9d8458b16e9c7ce6e07c712c02b8471dbc
server urls "https://debuginfod.archlinux.org/"
checking build-id
checking cache dir /home/amerey/.cache/debuginfod_client
not found No such file or directory (err=-2)
Server query failed: No such file or directory
```

No calls to curl_multi_wait occur. Is there a "cache_miss_s" file in the top
level of your debuginfod cache? It should contain the number of seconds
that must elapse after a failed attempt before another query would be
attempted (default is 600 seconds).

Aaron