diff options
author | Johan Herland <johan@herland.net> | 2020-02-04 00:04:44 +0300 |
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committer | Junio C Hamano <gitster@pobox.com> | 2020-02-04 23:20:27 +0300 |
commit | e1c52539510131b498087e177fe93d0bac744a5b (patch) | |
tree | 958ba24017142e05c71c2c76ce534f3f76e35843 /notes.c | |
parent | b6d4d82bd5a49197d5d2f4f81c08da0d461cfcf1 (diff) |
t3305: check notes fanout more carefully and robustly
In short, before this patch, this test script:
- creates many notes
- verifies that all notes in the notes tree has a fanout of 1
- removes most notes
- verifies that the notes in the notes tree now has a fanout of 0
The fanout verification only happened twice: after creating all the
notes, and after removing most of them.
This patch strengthens the test by checking the fanout after _each_
added/removed note: We assert that the switch from fanout 0 -> 1
happens exactly once while adding notes (and that the switch pervades
the entire notes tree). Likewise, we assert that the switch from
fanout 1 -> 0 happens exactly once while removing notes.
Additionally, we decrease the number of notes left after removal,
from 50 to 15 notes, in order to ensure that fanout 1 -> 0 transition
keeps happening regardless of external factors[1].
[1]: Currently (with the SHA1 hash function and the deterministic
object ids of the test environment) the fanout heuristic in the notes
code happens to switch from 0 -> 1 at 109 notes, and from 1 -> 0 at
59 notes. However, changing the hash function or other external
factors will vary these numbers, and the latter may - in theory - go
as low as 15. For more details, please see the discussion at
https://public-inbox.org/git/20200125230035.136348-4-sandals@crustytoothpaste.net/
Cc: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Cc: Brian M. Carlson <sandals@crustytoothpaste.net>
Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'notes.c')
0 files changed, 0 insertions, 0 deletions