this changes most visble uses of master/slave terminology in tests.sh
and most uses of 'type master' or 'type slave' in named.conf files.
files in the checkconf test were not updated in order to confirm that
the old syntax still works. rpzrecurse was also left mostly unchanged
to avoid interference with DNSRPS.
(cherry picked from commit e43b3c1fa1)
In order to lower the amount of memory allocated at startup by named
instances used in the BIND system test suite, set the default value of
"max-cache-size" for these to 2 megabytes. The purpose of this change
is to prevent named instances (or even entire virtual machines) from
getting killed by the operating system on the test host due to excessive
memory use.
Remove all "max-cache-size" statements from named configuration files
used in system tests ("checkconf" notwithstanding) to prevent confusion
as the "-T maxcachesize=..." command line option takes precedence over
configuration files.
(cherry picked from commit dad6572093)
The named configuration files used in the "geoip2" system test cause a
rather large number of views (6-8) to be set up in each tested named
instance. Each view has its own cache.
Commit aa72c31422 caused the RBT hash
table to be pre-allocated to a size derived from "max-cache-size", so
that it never needs to be rehashed. The size of that hash table is not
expected to be significant enough to cause memory use issues in typical
conditions even for large "max-cache-size" settings.
However, these two factors combined can cause memory exhaustion issues
in GitLab CI, where we run multiple "instances" of the test suite in
parallel on the same runner, each test suite executes multiple system
tests concurrently, and each system test may potentially start multiple
named instances at the same time. In practice, this problem currently
only seems to be affecting the "geoip2" system test, which is failing
intermittently due to named instances used by that test getting killed
by oom-killer.
Prevent the "geoip2" system test from failing intermittently by setting
"max-cache-size" in named configuration files used in that test to a low
value in order to keep memory usage at bay even with a large number of
views configured.
(cherry picked from commit 4292d5bdfe)
