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Date: Sat, 9 Apr 2022 00:21:08 +0200
From: Mark Wielaard <mark@klomp.org>
To: Milian Wolff <mail@milianw.de>
Cc: Aaron Merey <amerey@redhat.com>, elfutils-devel@sourceware.org
Subject: Re: caching failed lookups of debuginfo?
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Hi Milian,

On Fri, Apr 08, 2022 at 11:56:15PM +0200, Milian Wolff wrote:
> Which in turn points at the code that does cache cleanup in 
> `debuginfod_query_server`. I now used `rr` to record such a bogus run and I 
> clearly see that `(time(NULL) - st.st_mtime <= cache_miss)` is false and it 
> goes into the unlink case.
> 
> I'll try to debug this further now - I definitely do not wait 600s inbetween 
> these runs here...

I can replicate this on an debian system with /home on ext4.  st_mtime
doesn't seem to change ever. When the file is created the st_mtime
seems to be in the past. So time(NULL) - st.st_mtime <= cache_miss is
always false. I am not sure why yet.

Cheers,

Mark