[pkg-gnupg-maint] Bug#818972: gnupg2: Updating trustdb is several orders of magnitude slower in v2.1 than v1.x

[Matthew Walster]

Source: gnupg2
Version: 2.1.11-6
Severity: important
Tags: upstream

Dear Maintainer,

Using gpg v1.x, updating my trustdb took a few seconds. In gpg v2.1,
which I have just upgraded all my keyrings to, this process takes
several minutes. It remains busy at 100% CPU (single process) until the
activity is completed, and massively slows down importing / signing keys
etc.

A recent "refresh-keys" took nearly 5 minutes to complete, with the
results:

[...]
gpg: Total number processed: 360
gpg:              unchanged: 358
gpg:         new signatures: 4
gpg:     signatures cleaned: 2
gpg: marginals needed: 3  completes needed: 1  trust model: PGP
gpg: depth: 0  valid:   2  signed: 142  trust: 0-, 0q, 0n, 0m, 0f, 2u
gpg: depth: 1  valid: 142  signed: 136  trust: 59-, 0q, 0n, 6m, 77f, 0u
gpg: depth: 2  valid:  27  signed:  72  trust: 12-, 0q, 0n, 2m, 13f, 0u
gpg: depth: 3  valid:   3  signed:   6  trust: 0-, 1q, 0n, 0m, 2f, 0u
gpg: next trustdb check due at 2016-03-23

I believe this is being tracked upstream in
https://bugs.gnupg.org/gnupg/issue2019


-- System Information:
Debian Release: stretch/sid
  APT prefers testing-updates
  APT policy: (500, 'testing-updates'), (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.3.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=C (charmap=UTF-8) (ignored: LC_ALL set to en_GB.UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)