Add new command line knob '-r', that disables runas similar to '-n',
it's implied as well for kore command runs.
Add default runas (nobody) user and chroot (/var/empty) path, if none
are specified, fallback to these.
This configuration option limits the maximum number
of connections a worker process can accept() in a single
event loop.
It can be used to more evenly spread out incoming connections
across workers when new connections arrive in a burst.
In cases where accept() failed Kore would not relinquish the
lock towards other worker processes.
This becomes evident when dealing with a high number of concurrent
connections to the point the fd table gets full. In this scenario
the worker with the full fd table will spin on attempt to accept
newer connections.
As a bonus, Kore now has allows exactly up to worker_max_connections
of connections per worker before no longer attempting to grab the
accept lock.
Introduces two new configuration knobs:
* socket_backlog (backlog for listen(2))
* http_request_limit
The second one is the most interesting one.
Before, kore would iterate over all received HTTP requests
in its queue before returning out of http_process().
Under heavy load this queue can cause Kore to spend a considerable
amount of time iterating over said queue. With the http_request_limit,
kore will process at MOST http_request_limit requests before returning
back to the event loop.
This means responses to processed requests are sent out much quicker
and allows kore to handle any other incoming requests more gracefully.
Introduces a few new api functions:
- kore_websocket_handshake(struct http_request *):
Performs the handshake on an HTTP request (coming from page handler)
- kore_websocket_send(struct connection *, u_int8_t, void *, size_t):
Sends data to a websocket connection.
- kore_websocket_broadcast(struct connection *, u_int8_t, void *, size_t, int):
Broadcast the given websocket op and data to all connected
websocket clients on the worker. Note that as of right now
the WEBSOCKET_BROADCAST_GLOBAL scope option does not work
yet and messages broadcasted will be restricted to workers
only.
- kore_worker_websocket_broadcast(struct connection *, void *, void *):
Backend function used by kore_websocket_broadcast().
Could prove useful for developers to have access to.
A simple example is given under examples/websocket.
Known issues:
Kore does not support PING or CONT frames just yet.
Otherwise in a weird scenario the idle timer could
be started with a more recent time then the time we
test against causing a connection to disconnect
before its idle timer was over.
- The net code no longer has a recv_queue, instead reuse same recv buffer.
- Introduce net_recv_reset() to reset the recv buffer when needed.
- Have the workers spread the load better between them by slightly
delaying their next accept lock and giving them an accept treshold
so they don't go ahead and keep accepting connections if they end
up winning the race constantly between the workers.
- The kore_worker_acceptlock_release() is no longer available.
- Prepopulate the HTTP server response header that is added to each
response in both normal HTTP and SPDY modes.
- The path and host members of http_request are now allocated on the heap.
These changes overall result better performance on a multicore machine,
especially the worker load changes shine through.
Allow Kore to use per domain CRLs when requiring client certificates.
The require_client_cert configuration option has been renamed to a more
sane client_certificates and can optionally take a second argument
which is the CRL in pem format.
You'll need a restart in case the CRLs get updated.
After revisiting why this exists in Kore I decided it
does not belong in this platform and instead of letting
it sit there staring at me I rather just kill it.
Kore no longer passes the accept lock to the "next in line"
worker but instead all workers will attempt to grab the lock
if they can.
Also remember if we had the lock previous iteration of the
event loop and don't constantly disable/enable the accepting sockets.
Makes Kore scale even better across multiple cpu's.
Has support for full async pgsql queries. Most of the logic
is hidden behind a KORE_PGSQL() macro allowing you to insert
these pgsql calls in your page handlers without blocking the
kore worker while the query is going off.
There is place for improvement here, and perhaps KORE_PGSQL won't
stay as I feel this might overcomplicate things instead of making
them simpler as I thought it would.
If a worker reached worker_max_connections and it was its turn to
grab the accept lock it would've gotten stuck and no new connections
would be handled even if other workers would be less busy.
Instead, we now skip the lock if we're too busy and pass it along
in the hopes other workers are less busy.
This allows us to move the accept lock manually to another Kore worker
in case we own it and are about to do some heavy lifting on the current
Kore worker.
Joris Vink
Thordur Bjornsson