Why does gpg -k write to tofu.db?

[Brian Minton]

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On Tue, Aug 11, 2020 at 5:32 PM Brian Minton wrote:
>
> I have a lot of public keys in my keybox (it's about 45 MB or so).
> I was trying to figure out why seemingly innocent tasks in gpg take
> a very long time.  It seems that gnupg is making a very long
> running transaction to the sqlite3 database ~/.gnupg/tofu.db
>

This did eventually complete:
pops-mintonw10:~/.gnupg$ time gpg -k|wc -l
13729

real 117m26.112s
user 25m56.486s
sys 90m31.859s

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