Once we resume a query, we should clear DNS_FETCHOPT_TRYSTALE_ONTIMEOUT
from the options to prevent triggering the stale-answer-client-timeout
on subsequent fetches.
If we don't this may cause a crash when for example when prefetch is
triggered after a query restart.
Add a test case where a client request is received and the stale
timeout occurs, but it is not served stale data because there is no entry
in the cache, then is served an authoritative answer once the background
fetch completes. This ensures that a stale timeout only affects a
subsequent response if the client was answered.
when a serve-stale answer has been sent, the client continues waiting
for a proper answer. if a final completion event for the client does
arrive, it can just be cleaned up without sending a response, similar
to a canceled fetch.
- send a query for an AAAA which will be resolved as a mapped A
- disable authoritative responses
- wait for the negative AAAA response to become stale
- send another query, wait for the stale answer
- re-enable authorative responses so that a real answer arrives
- currently, this triggers an assertion in query.c
On some platforms, the __attribute__ constructor and destructor won't
take priorities and the compilation failed. On such platform would be
macOS. For this reason, the constructor/destructor in the libisc was
reworked to not use priorities, but have a single constructor and
destructor that calls the appropriate routines in correct order.
This commit removes the extra priority because it's now not needed and
it also breaks a compilation on macOS with GCC 10.
In the shutdown system test multiple queries are sent to a resolver
instance, in the meantime we terminate the same resolver process for
which the queries were sent to, either via rndc stop or a SIGTERM
signal, that means the resolver may not be able to answer all those
queries, since it has initiated the shutdown process.
The dnspython library raises a dns.resolver.NoNameservers exception when
a resolver object fails to receive an answer from the specified list
of nameservers (resolver.nameservers list), we need to handle this
exception as this is something that may happen since we asked the
resolver to terminate, as a result it may not answer clients even if
an answer is available, as the operation will be canceled.
configuring with --enable-mutex-atomics flagged these incorrectly
initialised variables on systems where pthread_mutex_init doesn't
just zero out the structure.
The size of the array holding the pointers to clientmgr was created so
big it could hold the actual clientmgr objects, not just the pointer.
This commit fixes the size to be just the ncpus * sizeof(pointer).
The isc_nmiface_t type was holding just a single isc_sockaddr_t,
so we got rid of the datatype and use plain isc_sockaddr_t in place
where isc_nmiface_t was used before. This means less type-casting and
shorter path to access isc_sockaddr_t members.
At the same time, instead of keeping the reference to the isc_sockaddr_t
that was passed to us when we start listening, we will keep a local
copy. This prevents the data race on destruction of the ns_interface_t
objects where pending nmsockets could reference the sockaddr of already
destroyed ns_interface_t object.
* dns_journal_next() leaves the read point in the journal after the
transaction header so journal_seek() should be inside the loop.
* we need to recover from transaction header inconsistencies
Additionally when correcting for <size, serial0, serial1, 0> the
correct consistency check is isc_serial_gt() rather than
isc_serial_ge(). All instances updated.
BIND installation should be done by setting DESTDIR during "make
install" not by setting prefix via ./configure.
Make sure that installation with DESTDIR=<PATH> works by checking that
named binary and it's respective man page were installed and that
well-known BIND9 directories - and only them - are present in DESTDIR.
Also rename install path variable from BIND_INSTALL_PATH to
INSTALL_PATH to avoid namespace clash in stress tests which use
BIND_INSTALL_PATH variable to configure path to BIND9 binaries.
Ubuntu 16.04 (Xenial Xerus) is reaching End of Standard Support in April
2021 thus we are removing it from the list of supported platforms and
replacing it with Ubuntu 18.04 LTS (Bionic Beaver).
According to the measurements (recorded on GL!5085), the fillcount of 2
for namepool and fillcount of 4 for rdspool can fit 99.99% of request
for tested scenarios.
This was discovered by perf recording the single second recursive test
using flamethrower where the initial malloc lit up like a flare.
Previously, as a way of reducing the contention between threads a
clientmgr object would be created for each interface/IP address.
We tasks being more strictly bound to netmgr workers, this is no longer
needed and we can just create clientmgr object per worker queue (ncpus).
Each clientmgr object than would have a single task and single memory
context.
Similarly, the resolver code would create hundreds of memory contexts
just on the resolver setup. The contention will be reduced directly in
the allocator, so for now just attach to the view memory instead of
creating separate memory context for each bucket.
Since a client object is bound to a netmgr handle, each client
will always be processed by the same netmgr worker, so we can
simplify the code by binding client->task to the same thread as
the client. Since ns__client_request() now runs in the same event
loop as client->task events, is no longer necessary to pause the
task manager before launching them.
Also removed some functions in isc_task that were not used.
The number of memory contexts created in the clientmgr was enormous. It
could easily create thousands of memory contexts because the formula was:
nprotocols * ncpus * ninterfaces * CLIENT_NMCTXS_PERCPU (8)
The original goal was to reduce the contention when allocating the
memory, but after a while nobody noticed that the amount of memory
context allocated would not reduce contention at all.
This commit removes the whole mctxpool and just uses the mctx from
clientmgr as the contention will be reduced directly in the allocator.
Running gcc:tarball CI job for merge requests is consistent with how we
run gcc:out-of-tree CI job and should help identify problems with the
build system during the review process, not once merged during daily
runs. For the sake of time, unit and system tests associated with the
gcc:tarball CI job are excluded from merge requests.
