As seen in commits 33a4461fa ("BUG/MINOR: stats: Fix Lua's `get_stats`
function") and a46b142e8 ("BUG/MINOR: Missing stat_field_names (since
f21d17bb)") it seems frequent to omit to update stats_fields[] when
adding a new ST_F_xxx entry. This breaks Lua's get_stats() and shows
a "(null)" in the header of "show stat", but that one is not detectable
to the naked eye anymore.
Let's add a reminder above the enum declaration about this, and a small
reg tests checking for the absence of "(null)". It was verified to fail
before the last patch above.
Some regtests involve multiple requests from multiple clients, which can
be dispatched as multiple requests to a server. It turns out that the
idle connection sharing works so well that very quickly few connections
are used, and regularly some of the remaining idle server connections
time out at the moment they were going to be reused, causing those random
"HTTP header incomplete" traces in the logs that make them fail often. In
the end this is only an artefact of the test environment.
And indeed, some tests like normalize-uri which perform a lot of reuse
fail very often, about 20-30% of the times in the CI, and 100% of the
time in local when running 1000 tests in a row. Others like ubase64,
sample_fetches or vary_* fail less often but still a lot in tests.
This patch addresses this by adding "tune.idle-pool.shared off" to all
tests which have at least twice as many requests as clients. It proves
very effective as no single error happens on normalize-uri anymore after
10000 tests. Also 100 full runs of all tests yield no error anymore.
One test is tricky, http_abortonclose, it used to fail ~10 times per
1000 runs and with this workaround still fails once every 1000 runs.
But the test is complex and there's a warning in it mentioning a
possible issue when run in parallel due to a port reuse.
This regtest verifies that the stats webpage can be used to change a
server state to maintenance or drain, and that filtering the page scope
will result in a filtered page.
